diff --git a/.editorconfig b/.editorconfig index 2c0e19c8..3692b3d7 100644 --- a/.editorconfig +++ b/.editorconfig @@ -7,3 +7,4 @@ charset = utf-8 indent_style = space indent_size = 2 trim_trailing_whitespace = true +max_line_length = off diff --git a/.gitattributes b/.gitattributes new file mode 100644 index 00000000..fcadb2cf --- /dev/null +++ b/.gitattributes @@ -0,0 +1 @@ +* text eol=lf diff --git a/.github/pull_request_template.md b/.github/pull_request_template.md index e978aa66..730fce5e 100644 --- a/.github/pull_request_template.md +++ b/.github/pull_request_template.md @@ -1,8 +1,15 @@ -Please read the CONTRIBUTING.md first. The most important parts regarding the actual entry: +## Suggestion type -- Write about it's unique selling point compared to other projects. -- If it's a commercial project, then mark it as such, e.g. `[Title ![c]](URL)`. -- Ensure that you provide concise and informative descriptions. -- Do not use a description like "A library/project/tool/framework for JSON processing in Java" since all of this is implied. -- Finish the description with a dot. -- Try to order it alphabetically. +- [ ] Project +- [ ] Resource + +## Checklist + +- [ ] I searched the list and existing issues for duplicates. +- [ ] I changed `README_SOURCE.md`, not the generated `README.md`. +- [ ] This pull request contains one suggestion. +- [ ] The suggestion is relevant to Java or the JVM and fits its chosen category. +- [ ] I used the canonical project or resource link. +- [ ] The suggestion is current and maintained. +- [ ] The concise, neutral description explains its distinguishing value and ends with punctuation. +- [ ] Licensing is clear and any restrictive terms are disclosed where applicable. diff --git a/.github/scripts/GenerateReadme.java b/.github/scripts/GenerateReadme.java new file mode 100644 index 00000000..2eb76ae3 --- /dev/null +++ b/.github/scripts/GenerateReadme.java @@ -0,0 +1,1188 @@ +// SPDX-License-Identifier: MIT + +import java.io.IOException; +import java.net.URI; +import java.net.http.HttpClient; +import java.net.http.HttpRequest; +import java.net.http.HttpResponse; +import java.nio.file.AtomicMoveNotSupportedException; +import java.nio.file.Files; +import java.nio.file.Path; +import java.nio.file.StandardCopyOption; +import java.time.Duration; +import java.time.LocalDate; +import java.time.OffsetDateTime; +import java.time.ZoneOffset; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.Comparator; +import java.util.HashMap; +import java.util.HashSet; +import java.util.LinkedHashMap; +import java.util.List; +import java.util.Locale; +import java.util.Map; +import java.util.Optional; +import java.util.Set; +import java.util.TreeMap; +import java.util.TreeSet; +import java.util.regex.Pattern; +import java.util.stream.Collectors; + +final class GenerateReadme { + private static final int MAX_GITHUB_ATTEMPTS = 3; + private static final Pattern STARS = Pattern.compile("\"stargazers_count\"\\s*:\\s*(\\d+)"); + private static final Pattern PUSHED_AT = Pattern.compile("\"pushed_at\"\\s*:\\s*(?:\"([^\"]+)\"|null)"); + private static final Pattern ARCHIVED = Pattern.compile("\"archived\"\\s*:\\s*(true|false)"); + private static final Pattern LICENSE = Pattern.compile( + "\"license\"\\s*:\\s*(?:null|\\{.*?\"spdx_id\"\\s*:\\s*(?:\"([^\"]+)\"|null))", + Pattern.DOTALL + ); + private static final Pattern GITHUB_METADATA = + Pattern.compile("\\s*\\s*$"); + private static final Pattern REPOSITORY = + Pattern.compile("[A-Za-z0-9_.-]+/[A-Za-z0-9_.-]+"); + private static final Comparator TEXT_ORDER = + Comparator.comparing((String value) -> value.toLowerCase(Locale.ROOT)) + .thenComparing(Comparator.naturalOrder()); + + public static void main(String[] args) throws Exception { + if (args.length == 0) { + usage(); + System.exit(2); + } + + switch (args[0]) { + case "check" -> { + var sourcePath = Path.of(args.length > 1 ? args[1] : "README_SOURCE.md"); + var source = parseSource(sourcePath); + validateSource(source); + printSourceSummary(source); + } + case "check-added" -> checkAdded(args); + case "self-test" -> selfTest(); + case "generate" -> generate(args); + default -> { + usage(); + System.exit(2); + } + } + } + + private static void usage() { + System.err.println(""" + Usage: + java .github/scripts/GenerateReadme.java check [source] + java .github/scripts/GenerateReadme.java check-added [source] + java .github/scripts/GenerateReadme.java self-test + java .github/scripts/GenerateReadme.java generate [source] [output] [cache] [--refresh-all] [--branch name] + """); + } + + private static void checkAdded(String[] args) throws Exception { + if (args.length < 2 || args.length > 3) { + throw new IllegalArgumentException("check-added requires a base source and optional current source"); + } + var base = parseSource(Path.of(args[1])); + var source = parseSource(Path.of(args.length == 3 ? args[2] : "README_SOURCE.md")); + validateSource(source); + var added = addedRepositories(base, source); + if (added.isEmpty()) { + System.out.println("No new GitHub repositories to validate"); + return; + } + + var client = githubClient(); + var token = githubToken(); + for (var repository : added) { + var stats = fetchStats(client, repository, token); + require(!stats.archived(), 0, "Archived GitHub repository: " + repository); + } + System.out.printf("Validated %d new GitHub repositories%n", added.size()); + } + + private static void generate(String[] args) throws Exception { + var sourcePath = Path.of(args.length > 1 ? args[1] : "README_SOURCE.md"); + var outputPath = Path.of(args.length > 2 ? args[2] : "README.md"); + var cachePath = Path.of(args.length > 3 ? args[3] : ".cache/github-stats.tsv"); + var refreshAll = false; + var branch = System.getenv().getOrDefault("GITHUB_REF_NAME", "main"); + + for (var i = 4; i < args.length; i++) { + switch (args[i]) { + case "--refresh-all" -> refreshAll = true; + case "--branch" -> { + if (++i >= args.length) { + throw new IllegalArgumentException("--branch requires a value"); + } + branch = args[i]; + } + default -> throw new IllegalArgumentException("Unknown option: " + args[i]); + } + } + + var source = parseSource(sourcePath); + validateSource(source); + + var repositories = repositories(source); + + var cache = readCache(cachePath); + var missing = repositories.stream().filter(repo -> !cache.stats().containsKey(repo)).toList(); + var targets = refreshAll ? List.copyOf(repositories) : missing; + var stats = new HashMap<>(cache.stats()); + var today = LocalDate.now(ZoneOffset.UTC); + + if (!targets.isEmpty()) { + var token = githubToken(); + var client = githubClient(); + + for (var i = 0; i < targets.size(); i++) { + var repository = targets.get(i); + stats.put(repository, fetchStats(client, repository, token)); + if ((i + 1) % 25 == 0 || i + 1 == targets.size()) { + System.out.printf("Fetched %d/%d repositories%n", i + 1, targets.size()); + } + } + } + + stats.keySet().retainAll(repositories); + var refreshed = refreshAll || cache.refreshed() == null ? today : cache.refreshed(); + var updatedCache = new StatsCache(refreshed, stats); + rejectArchivedProjects(source, updatedCache); + var rendered = render(source, updatedCache, today, branch); + validateRendered(source, updatedCache, rendered, today); + + writeCache(cachePath, updatedCache); + writeAtomically(outputPath, rendered); + printGeneratedSummary(source, updatedCache, today, outputPath); + } + + private static Catalog parseSource(Path path) throws IOException { + var lines = Files.readAllLines(path); + var title = lines.stream().filter(line -> line.startsWith("# ")).findFirst() + .orElseThrow(() -> new IllegalArgumentException("Missing title")); + var titleIndex = lines.indexOf(title); + var tagline = lines.subList(titleIndex + 1, lines.size()).stream() + .map(String::trim) + .filter(line -> !line.isEmpty() && !line.startsWith("\n\n") + .append(source.title()).append("\n\n") + .append(source.tagline()).append("\n\n") + .append("").append(projectCount(source)).append(" projects Β· ") + .append(source.categories().size()).append(" categories Β· ") + .append(resourceCount(source)).append(" resources\n\n") + .append("Activity: 🟒 pushed within 3 months Β· 🟠 pushed 3–12 months ago Β· ") + .append("πŸ”΄ no push for over 12 months\n\n") + .append("License chips use GitHub SPDX metadata when available.\n\n") + .append("Entries spanning several repositories combine their stars, use the most recent push for activity ") + .append("and show a license only when all repositories agree.\n\n") + .append("## Projects\n\n"); + + source.categories().stream() + .sorted(Comparator.comparing(category -> category.name, TEXT_ORDER)) + .forEach(category -> renderCategory(out, category, cache, today)); + + out.append("## Resources\n\n"); + for (var resource : source.resources()) { + renderResource(out, resource); + } + + var editUrl = "https://github.com/akullpp/awesome-java/edit/" + branch + "/README_SOURCE.md"; + out.append("## Contributing\n\n") + .append("> **[Suggest a project or resource](").append(editUrl).append(")** Β· ") + .append("[Contribution guidelines](CONTRIBUTING.md)\n") + .append(">\n") + .append("> Add one Markdown entry under the appropriate category and open one pull request.
\n") + .append("> Ordering, counts and GitHub statistics are generated automatically.\n\n") + .append("## License\n\n") + .append("Catalog and documentation: [CC BY-SA 4.0](LICENSE).
\n") + .append("Automation code and configuration: [MIT](LICENSE-CODE).\n"); + return out.toString(); + } + + private static void renderCategory( + StringBuilder out, + Category category, + StatsCache cache, + LocalDate today + ) { + var count = category.items.size() + + category.subcategories.values().stream().mapToInt(sub -> sub.items.size()).sum(); + out.append("
\n") + .append("").append(category.name).append(" ") + .append(count).append(count == 1 ? " project" : " projects").append("\n\n") + .append('_').append(category.description).append("_\n\n"); + + category.items.stream() + .sorted(Comparator.comparing(Item::name, TEXT_ORDER)) + .forEach(item -> renderProject(out, item, cache, today)); + + category.subcategories.values().stream() + .sorted(Comparator.comparing(sub -> sub.name, TEXT_ORDER)) + .forEach(sub -> { + out.append("#### ").append(sub.name).append(" ") + .append(sub.items.size()).append(sub.items.size() == 1 ? " project" : " projects") + .append("\n\n"); + if (!sub.description.isBlank()) { + out.append('_').append(sub.description).append("_\n\n"); + } + sub.items.stream() + .sorted(Comparator.comparing(Item::name, TEXT_ORDER)) + .forEach(item -> renderProject(out, item, cache, today)); + }); + + out.append("
\n\n"); + } + + private static void renderProject( + StringBuilder out, + Item item, + StatsCache cache, + LocalDate today + ) { + out.append("> **[").append(item.name()).append("](").append(item.url()).append(")**"); + aggregateStats(item, cache).ifPresent(stats -> { + out.append(" β˜… ").append(formatStars(stats.stars())).append(""); + if (stats.license() != null) { + out.append(" ").append(stats.license()).append(""); + } + if (stats.pushed() != null) { + out.append(' ').append(activityDot(stats.pushed(), today)); + } + }); + out.append("
").append(item.description()).append("\n\n"); + } + + private static void renderResource(StringBuilder out, ResourceGroup resource) { + out.append("
\n") + .append("").append(resource.name).append(" ") + .append(resource.items.size()).append(resource.items.size() == 1 ? " link" : " links") + .append("\n\n") + .append('_').append(resource.description).append("_\n\n"); + + resource.items.stream() + .sorted(Comparator.comparing(Item::name, TEXT_ORDER)) + .forEach(item -> { + out.append("> **[").append(item.name()).append("](").append(item.url()).append(")**"); + if (!item.description().isBlank()) { + out.append("
").append(item.description()); + } + out.append("\n\n"); + }); + out.append("
\n\n"); + } + + private static Optional aggregateStats(Item item, StatsCache cache) { + if (item.repositories().isEmpty()) { + return Optional.empty(); + } + + long stars = 0; + LocalDate pushed = null; + String license = null; + var oneLicense = true; + for (var repository : item.repositories()) { + var stats = cache.stats().get(repository); + require(stats != null, item.lineNumber(), + "Missing GitHub statistics for " + repository); + stars += stats.stars(); + if (stats.pushed() != null && (pushed == null || stats.pushed().isAfter(pushed))) { + pushed = stats.pushed(); + } + if (stats.license() == null) { + oneLicense = false; + } else if (license == null) { + license = stats.license(); + } else if (!license.equals(stats.license())) { + oneLicense = false; + } + } + return Optional.of(new RepoStats(stars, pushed, false, oneLicense ? license : null)); + } + + private static void rejectArchivedProjects(Catalog source, StatsCache cache) { + for (var item : source.projects()) { + for (var repository : item.repositories()) { + var stats = cache.stats().get(repository); + require(stats != null, item.lineNumber(), + "Missing GitHub statistics for " + repository); + require(!stats.archived(), item.lineNumber(), + "Archived GitHub repository: " + repository); + } + } + } + + private static void validateRendered( + Catalog source, + StatsCache cache, + String rendered, + LocalDate today + ) { + require(!rendered.contains("Last push"), 0, "Generated README contains a Last push label"); + require(!rendered.contains("| Name |"), 0, "Generated README contains a table"); + require(!rendered.contains("![c]") && !rendered.contains("[c]:"), + 0, "Generated README contains the retired commercial badge"); + require(!rendered.matches("(?s).*\\d{2}/\\d{2}/\\d{4}.*"), 0, + "Generated README contains a per-project date"); + for (var item : source.projects()) { + require(rendered.contains("**[" + item.name() + "](" + item.url() + ")**"), item.lineNumber(), + "Generated README is missing project: " + item.name()); + aggregateStats(item, cache).filter(stats -> stats.license() != null).ifPresent(stats -> + require(rendered.contains("β˜… " + formatStars(stats.stars()) + " " + + stats.license() + ""), + item.lineNumber(), "Generated README is missing license: " + item.name()) + ); + } + for (var resource : source.resources()) { + for (var item : resource.items) { + require(rendered.contains("**[" + item.name() + "](" + item.url() + ")**"), item.lineNumber(), + "Generated README is missing resource: " + item.name()); + } + } + + var expectedLicenses = source.projects().stream() + .map(item -> aggregateStats(item, cache)) + .flatMap(Optional::stream) + .filter(stats -> stats.license() != null) + .count(); + var actualLicenses = rendered.lines() + .filter(line -> line.startsWith("> **[") + && line.contains("β˜… ") + && line.contains(" ")) + .count(); + require(actualLicenses == expectedLicenses, 0, + "Expected " + expectedLicenses + " license chips, found " + actualLicenses); + + var expectedDots = source.projects().stream() + .map(item -> aggregateStats(item, cache)) + .flatMap(Optional::stream) + .filter(stats -> stats.pushed() != null) + .count(); + var actualDots = rendered.codePoints() + .filter(codePoint -> codePoint == "🟒".codePointAt(0) + || codePoint == "🟠".codePointAt(0) + || codePoint == "πŸ”΄".codePointAt(0)) + .count(); + require(actualDots == expectedDots + 3, 0, + "Expected " + expectedDots + " project dots plus the legend, found " + actualDots); + } + + private static void printSourceSummary(Catalog source) { + System.out.printf( + "Valid source: %d projects, %d categories, %d nested groups, %d resources in %d groups%n", + projectCount(source), + source.categories().size(), + source.categories().stream().mapToInt(category -> category.subcategories.size()).sum(), + resourceCount(source), + source.resources().size() + ); + } + + private static void printGeneratedSummary( + Catalog source, + StatsCache cache, + LocalDate today, + Path output + ) { + var projectStats = source.projects().stream() + .map(item -> aggregateStats(item, cache)) + .flatMap(Optional::stream) + .toList(); + var green = projectStats.stream() + .filter(stats -> stats.pushed() != null && activityDot(stats.pushed(), today).equals("🟒")).count(); + var orange = projectStats.stream() + .filter(stats -> stats.pushed() != null && activityDot(stats.pushed(), today).equals("🟠")).count(); + var red = projectStats.stream() + .filter(stats -> stats.pushed() != null && activityDot(stats.pushed(), today).equals("πŸ”΄")).count(); + printSourceSummary(source); + System.out.printf( + "Generated %s with %d scored projects: 🟒 %d, 🟠 %d, πŸ”΄ %d%n", + output, + projectStats.size(), + green, + orange, + red + ); + } + + private static int projectCount(Catalog source) { + return source.categories().stream().mapToInt(category -> + category.items.size() + + category.subcategories.values().stream().mapToInt(sub -> sub.items.size()).sum() + ).sum(); + } + + private static int resourceCount(Catalog source) { + return source.resources().stream().mapToInt(resource -> resource.items.size()).sum(); + } + + private static String activityDot(LocalDate pushed, LocalDate today) { + if (!pushed.isBefore(today.minusMonths(3))) { + return "🟒"; + } + if (!pushed.isBefore(today.minusMonths(12))) { + return "🟠"; + } + return "πŸ”΄"; + } + + private static String formatStars(long stars) { + return stars < 1_000 ? Long.toString(stars) : String.format(Locale.ROOT, "%.1fk", stars / 1_000.0); + } + + private static Optional githubRepository(String url) { + try { + var uri = URI.create(url); + if (!"github.com".equalsIgnoreCase(uri.getHost())) { + return Optional.empty(); + } + var parts = Arrays.stream(uri.getPath().split("/")) + .filter(part -> !part.isBlank()) + .toList(); + if (parts.size() < 2) { + return Optional.empty(); + } + var repository = parts.get(1).replaceFirst("\\.git$", ""); + return Optional.of(parts.get(0) + "/" + repository); + } catch (IllegalArgumentException ignored) { + return Optional.empty(); + } + } + + private static void validateUrl(String url, int lineNumber) { + try { + var uri = URI.create(url); + require("https".equalsIgnoreCase(uri.getScheme()) && uri.getHost() != null, + lineNumber, "Entry URL must be an absolute HTTPS URL: " + url); + } catch (IllegalArgumentException exception) { + fail(lineNumber, "Entry URL must be an absolute HTTPS URL: " + url); + } + } + + private static String slug(String value) { + return value.toLowerCase(Locale.ROOT) + .replaceAll("[^a-z0-9\\s-]", "") + .trim() + .replaceAll("[\\s-]+", "-"); + } + + private static String normalizeUrl(String url) { + return url.toLowerCase(Locale.ROOT).replaceAll("/+$", ""); + } + + private static String knownLicense(String license) { + return license == null || license.isBlank() + || license.equals("NOASSERTION") || license.equals("OTHER") + ? null + : license; + } + + private static boolean isDescription(String line) { + return line.length() >= 2 && line.startsWith("_") && line.endsWith("_"); + } + + private static String stripItalics(String line) { + return line.substring(1, line.length() - 1); + } + + private static void require(boolean condition, int lineNumber, String message) { + if (!condition) { + fail(lineNumber, message); + } + } + + private static void fail(int zeroBasedLineNumber, String message) { + var prefix = zeroBasedLineNumber > 0 ? "Line " + zeroBasedLineNumber + ": " : ""; + throw new IllegalArgumentException(prefix + message); + } + + private static void writeAtomically(Path path, String content) throws IOException { + var parent = path.toAbsolutePath().getParent(); + Files.createDirectories(parent); + var temporary = parent.resolve(path.getFileName() + ".tmp"); + Files.writeString(temporary, content); + try { + Files.move(temporary, path.toAbsolutePath(), StandardCopyOption.ATOMIC_MOVE, + StandardCopyOption.REPLACE_EXISTING); + } catch (AtomicMoveNotSupportedException ignored) { + Files.move(temporary, path.toAbsolutePath(), StandardCopyOption.REPLACE_EXISTING); + } + } + + private static void selfTest() throws Exception { + var today = LocalDate.of(2026, 7, 26); + require(activityDot(LocalDate.of(2026, 4, 26), today).equals("🟒"), 0, "Green boundary"); + require(activityDot(LocalDate.of(2026, 4, 25), today).equals("🟠"), 0, "Orange start"); + require(activityDot(LocalDate.of(2025, 7, 26), today).equals("🟠"), 0, "Orange boundary"); + require(activityDot(LocalDate.of(2025, 7, 25), today).equals("πŸ”΄"), 0, "Red boundary"); + require(formatStars(999).equals("999"), 0, "Small star formatting"); + require(formatStars(1_000).equals("1.0k"), 0, "Thousand star formatting"); + require(formatStars(12_749).equals("12.7k"), 0, "Large star formatting"); + require(githubRepository("https://github.com/TNG/ArchUnit").orElseThrow().equals("TNG/ArchUnit"), + 0, "Repository parsing"); + require(githubRepository("https://github.com/webforms-core").isEmpty(), 0, + "Organization URL parsing"); + require(isRetryableStatus(429), 0, "Rate-limit retry"); + require(isRetryableStatus(500) && isRetryableStatus(503), 0, "Server-error retry"); + require(!isRetryableStatus(403) && !isRetryableStatus(404), 0, + "Permanent GitHub errors"); + var baseCategory = new Category("Base"); + baseCategory.items.add(parseItem( + "- [Existing](https://github.com/Acme/one) - Existing project.", + 1, + true + )); + var changedCategory = new Category("Changed"); + changedCategory.items.add(parseItem( + "- [Existing](https://github.com/acme/one) - Existing project.", + 1, + true + )); + changedCategory.items.add(parseItem( + "- [Added](https://example.com) - Added project. " + + "", + 2, + true + )); + var baseRepositories = new Catalog("# Base", "Base.", List.of(baseCategory), List.of()); + var changedRepositories = + new Catalog("# Changed", "Changed.", List.of(changedCategory), List.of()); + require( + new HashSet<>(addedRepositories(baseRepositories, changedRepositories)) + .equals(Set.of("acme/two", "acme/three")), + 0, + "Added repository comparison" + ); + require(addedRepositories(changedRepositories, baseRepositories).isEmpty(), 0, + "Removed repositories are ignored"); + var umbrella = parseItem( + "- [Umbrella](https://example.com) - Several modules. " + + "", + 2, + true + ); + require(umbrella.repositories().equals(List.of("acme/one", "acme/two")), 0, + "Umbrella repository parsing"); + var aggregate = aggregateStats(umbrella, new StatsCache(today, Map.of( + "acme/one", new RepoStats(10, LocalDate.of(2026, 1, 1), false, "Apache-2.0"), + "acme/two", new RepoStats(20, LocalDate.of(2026, 7, 1), false, "Apache-2.0") + ))).orElseThrow(); + require(aggregate.stars() == 30, 0, "Umbrella star aggregation"); + require(aggregate.pushed().equals(LocalDate.of(2026, 7, 1)), 0, + "Umbrella activity aggregation"); + require(aggregate.license().equals("Apache-2.0"), 0, "Umbrella license aggregation"); + var mixedLicense = aggregateStats(umbrella, new StatsCache(today, Map.of( + "acme/one", new RepoStats(10, today, false, "Apache-2.0"), + "acme/two", new RepoStats(20, today, false, "MIT") + ))).orElseThrow(); + require(mixedLicense.license() == null, 0, "Mixed umbrella licenses"); + require(knownLicense("NOASSERTION") == null, 0, "Unknown license handling"); + var licensed = parseStats(""" + {"stargazers_count":1,"pushed_at":"2026-07-01T00:00:00Z","archived":false, + "license":{"spdx_id":"MIT"}} + """); + require("MIT".equals(licensed.license()), 0, "Concrete license parsing"); + var nullLicense = parseStats(""" + {"stargazers_count":1,"pushed_at":null,"archived":false,"license":null} + """); + require(nullLicense.license() == null, 0, "Null license parsing"); + var unknownLicense = parseStats(""" + {"stargazers_count":1,"pushed_at":null,"archived":false, + "license":{"spdx_id":"NOASSERTION"}} + """); + require(unknownLicense.license() == null, 0, "Unknown API license parsing"); + var category = new Category("Test"); + category.description = "Test projects."; + category.items.add(umbrella); + var catalog = new Catalog("# Test", "Test.", List.of(category), List.of()); + var resources = new ResourceGroup("Links"); + resources.description = "Useful links."; + resources.items.add(parseItem("- [Link](https://example.com/link)", 2, false)); + var rendered = render( + new Catalog("# Test", "Test.", List.of(category), List.of(resources)), + new StatsCache(today, Map.of( + "acme/one", new RepoStats(10, today, false, "Apache-2.0"), + "acme/two", new RepoStats(20, today, false, "Apache-2.0") + )), + today, + "test" + ); + require(rendered.contains("Suggest a project or resource"), 0, "Contribution CTA"); + require(rendered.contains("CC BY-SA 4.0") && rendered.contains("[MIT](LICENSE-CODE)"), + 0, "License footer"); + expectFailure( + () -> rejectArchivedProjects(catalog, new StatsCache(today, Map.of( + "acme/one", new RepoStats(10, today, false, "Apache-2.0"), + "acme/two", new RepoStats(20, today, true, "Apache-2.0") + ))), + "Archived GitHub repository" + ); + expectFailure( + () -> parseItem( + "- [Bad](https://github.com/acme/one) - Direct link. " + + "", + 3, + true + ), + "direct repository link" + ); + expectFailure( + () -> parseItem( + "- [Bad](https://example.com) - One repository. ", + 4, + true + ), + "at least two" + ); + var oldCache = Files.createTempFile("awesome-java-old-cache", ".tsv"); + try { + Files.writeString(oldCache, + "# refreshed=2026-07-26\nacme/one\t10\t2026-07-25\tfalse\n"); + expectFailure(() -> readCache(oldCache), "Invalid statistics cache line"); + } finally { + Files.deleteIfExists(oldCache); + } + var duplicateCache = Files.createTempFile("awesome-java-duplicate-cache", ".tsv"); + try { + Files.writeString(duplicateCache, """ + # refreshed=2026-07-26 + acme/one 10 2026-07-25 false MIT + acme/one 11 2026-07-26 false MIT + """); + expectFailure(() -> readCache(duplicateCache), "Duplicate repository"); + } finally { + Files.deleteIfExists(duplicateCache); + } + expectFailure(() -> validateFixture(""" + # Test + + Test. + + ## Projects + + ### Projects + + _Projects._ + + - Broken + + ## Resources + + ### Resources + + _Resources._ + + - [Resource](https://example.com) + """), "Unexpected project content"); + expectFailure(() -> validateFixture(""" + # Test + + Test. + + ## Projects + + ### Projects + + _Projects._ + + - [Project](not-a-url) - Project. + + ## Resources + + ### Resources + + _Resources._ + + - [Resource](https://example.com) + """), "absolute HTTPS URL"); + expectFailure(() -> validateFixture(""" + # Test + + Test. + + ## Projects + + ### Projects + + _Projects._ + + - [Project](https://example.com/project) - Project. + + ## Resources + + ### Resources + + _Resources._ + + - [One](https://example.com/resource) + - [Two](https://example.com/resource) + """), "Duplicate entry URL"); + expectFailure(() -> validateFixture(""" + # Test + + Test. + + ## Projects + + ### Projects + + _Projects._ + + - [Project](https://example.com/project) - Project. + + ## Resources + + ### Resources + + _Resources._ + """), "Empty resource group"); + System.out.println("Self-test passed"); + } + + private static void validateFixture(String content) throws IOException { + var path = Files.createTempFile("awesome-java-source", ".md"); + try { + Files.writeString(path, content); + validateSource(parseSource(path)); + } finally { + Files.deleteIfExists(path); + } + } + + private static void expectFailure(CheckedRunnable action, String message) { + try { + action.run(); + } catch (Exception exception) { + require(exception.getMessage().contains(message), 0, + "Unexpected failure: " + exception.getMessage()); + return; + } + fail(0, "Expected failure containing: " + message); + } + + @FunctionalInterface + private interface CheckedRunnable { + void run() throws Exception; + } + + private enum Section { + NONE, + PROJECTS, + RESOURCES + } + + private record Item( + String name, + String url, + String description, + int lineNumber, + List repositories + ) {} + + private static final class Category { + private final String name; + private String description = ""; + private final List items = new ArrayList<>(); + private final Map subcategories = new TreeMap<>(TEXT_ORDER); + + private Category(String name) { + this.name = name; + } + } + + private static final class Subcategory { + private final String name; + private String description = ""; + private final List items = new ArrayList<>(); + + private Subcategory(String name) { + this.name = name; + } + } + + private static final class ResourceGroup { + private final String name; + private String description = ""; + private final List items = new ArrayList<>(); + + private ResourceGroup(String name) { + this.name = name; + } + } + + private record Catalog( + String title, + String tagline, + List categories, + List resources + ) { + private List projects() { + var projects = new ArrayList(); + for (var category : categories) { + projects.addAll(category.items); + category.subcategories.values().forEach(subcategory -> projects.addAll(subcategory.items)); + } + return projects; + } + } + + private record RepoStats(long stars, LocalDate pushed, boolean archived, String license) {} + + private record StatsCache(LocalDate refreshed, Map stats) {} +} diff --git a/.github/workflows/update-readme.yml b/.github/workflows/update-readme.yml new file mode 100644 index 00000000..ee0aca4c --- /dev/null +++ b/.github/workflows/update-readme.yml @@ -0,0 +1,110 @@ +# SPDX-License-Identifier: MIT + +name: Update README + +on: + pull_request: + paths: + - "README_SOURCE.md" + - "README.md" + - "CONTRIBUTING.md" + - ".github/pull_request_template.md" + - ".github/workflows/update-readme.yml" + - "mise.toml" + - ".github/scripts/**" + push: + branches: + - main + - test + paths: + - "README_SOURCE.md" + - ".github/workflows/update-readme.yml" + - "mise.toml" + - ".github/scripts/**" + schedule: + - cron: "0 0 * * 1" + workflow_dispatch: + +permissions: + contents: read + +concurrency: + group: update-readme-${{ github.ref }} + cancel-in-progress: true + +jobs: + validate: + if: github.event_name == 'pull_request' + runs-on: ubuntu-latest + steps: + - uses: actions/checkout@v6 + with: + fetch-depth: 0 + - name: Reject direct README changes + env: + BASE_SHA: ${{ github.event.pull_request.base.sha }} + HEAD_SHA: ${{ github.event.pull_request.head.sha }} + run: | + if ! git diff --quiet "$BASE_SHA" "$HEAD_SHA" -- README.md; then + echo "::error file=README.md::README.md is generated. Edit README_SOURCE.md instead." + exit 1 + fi + - uses: jdx/mise-action@v3 + - name: Validate source and generator + run: | + java .github/scripts/GenerateReadme.java self-test + java .github/scripts/GenerateReadme.java check README_SOURCE.md + - name: Validate added GitHub repositories + env: + BASE_SHA: ${{ github.event.pull_request.base.sha }} + GITHUB_TOKEN: ${{ github.token }} + run: | + base_source="$RUNNER_TEMP/README_SOURCE.base.md" + if git cat-file -e "${BASE_SHA}:README_SOURCE.md"; then + git show "${BASE_SHA}:README_SOURCE.md" > "$base_source" + java .github/scripts/GenerateReadme.java check-added "$base_source" README_SOURCE.md + else + echo "::notice::Base branch has no README_SOURCE.md; skipping added repository validation." + fi + + update: + if: github.event_name != 'pull_request' + runs-on: ubuntu-latest + permissions: + contents: write + steps: + - uses: actions/checkout@v6 + with: + fetch-depth: 0 + - uses: jdx/mise-action@v3 + - name: Restore statistics cache + uses: actions/cache@v5 + with: + path: .cache/github-stats.tsv + key: readme-stats-v3-${{ github.ref_name }}-${{ github.run_id }} + restore-keys: | + readme-stats-v3-${{ github.ref_name }}- + - name: Validate source and generator + run: | + java .github/scripts/GenerateReadme.java self-test + java .github/scripts/GenerateReadme.java check README_SOURCE.md + - name: Generate README + env: + GITHUB_TOKEN: ${{ github.token }} + run: | + args=() + if [ "${{ github.event_name }}" = "schedule" ] || [ "${{ github.event_name }}" = "workflow_dispatch" ]; then + args+=(--refresh-all) + fi + java .github/scripts/GenerateReadme.java generate README_SOURCE.md README.md .cache/github-stats.tsv "${args[@]}" --branch "$GITHUB_REF_NAME" + - name: Commit README + run: | + git config --local user.email "41898282+github-actions[bot]@users.noreply.github.com" + git config --local user.name "github-actions[bot]" + git add README.md + if git diff --staged --quiet; then + echo "README is already current" + else + git commit -m "Update README with latest GitHub stats" + git push + fi diff --git a/.gitignore b/.gitignore new file mode 100644 index 00000000..0742a665 --- /dev/null +++ b/.gitignore @@ -0,0 +1,6 @@ +.idea/ +.vscode/ +.tmp/ +.cache/ +.DS_Store +*.class diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md index 1dc2762f..309b4c13 100644 --- a/CONTRIBUTING.md +++ b/CONTRIBUTING.md @@ -1,49 +1,76 @@ # Contribution Guidelines -Unfortunately, not every library/tool/framework can be considered. This list aims to provide a concise list of noteworthy modern software. This means that suggested software is: +## Suggest a Project -(a) widely recommended, regardless of personal opinion +Edit [`README_SOURCE.md`](README_SOURCE.md), add one line under the best category, +and open one pull request: -(b) highly discussed in the community due to its innovative nature +```markdown +- [Project Name](https://github.com/owner/repository) - A concise, neutral description ending with a period. +``` -(c) absolutely unique in its approach and function +Use the canonical GitHub repository when one exists. The generated `README.md` +handles ordering, counts, stars and activity; contributors do not need to run +the generator. -(d) a niche product that fills a gap +A project should: -Suggested software must also be developer-friendly, which means it meets the following criteria: +- make Java a primary API, runtime, implementation target or substantial + first-class integration; +- be noteworthy because it is widely recommended, innovative, unique or fills + a useful niche; +- provide English documentation and clear licensing; +- have clear pricing and a free tier when commercial. -(i) If an open source *application*, it is licensed under one of the open source licenses listed on https://opensource.org/licenses. +Known GitHub SPDX licenses appear automatically; do not repeat them in +descriptions or add license or commercial badges manually. If no chip is +available, disclose restrictive, noncommercial or source-available terms in +the entry. Keep descriptions short, factual and distinctive from similar +entries. Use `Miscellaneous` only when no focused category fits. -(ii) If an open source *library*, it is licensed under one of the open source licenses listed on https://opensource.org/licenses, with the exception of GPL and AGPL (due to their viral nature). +Search existing entries and issues before submitting. Self-promotion is +reviewed carefully but is welcome when the project meets the same criteria. +Use one pull request per project. -(iii) If commercial, it has clear pricing. +## Suggest a Resource -## Pull Requests +Add one resource under the best group in [`README_SOURCE.md`](README_SOURCE.md): -There are two required criteria for a pull request: +```markdown +- [Resource Name](https://canonical.example) +``` -1. If an entry has a similar scope as other entries in the same category, the description must state the unique features that distinguishes it from the other entries. +An optional description may follow the link: -2. If an entry does not meet conditions *(a)* to *(d)* there has to be an explanation either in the description or the pull request why it should be added to the list. +```markdown +- [Resource Name](https://canonical.example) - A concise, neutral description ending with punctuation. +``` -3. If an entry doesn't fit any of the pre-existing specialised sections, it should go under Miscellaneous. +Resources include books, podcasts, people, communities, related lists and +websites. They must be current, relevant to Java or the JVM, use a canonical +HTTPS link, fit the chosen group and use English where prose is involved. +Search for duplicates and submit one resource per pull request. Contributors +do not need to run the generator. -4. If two or more entries in Miscellaneous are in the same domain, then they can be moved to a new specialised section. +## Maintainer Notes -Self-promotion is frowned upon and viewed critically, but your suggestion will of course be approved if the criteria match. +Most entries point directly to one GitHub repository. For an umbrella project +whose Java offering genuinely spans several repositories, keep its public +homepage and append maintainer-only metadata: -If your entry isn't accepted, please check the [Issues](https://github.com/akullpp/awesome-java/issues) for items marked with the "question" tag to see if it had been previously discussed. If nothing comes up, feel free to create a new issue, adding the "question" tag. +```markdown +- [Project](https://example.com) - Description. +``` -Furthermore, please ensure your pull request follows the following guidelines: +Use at least two canonical repositories. A repository may belong to only one +entry. The generator sums their stars, uses their most recent push for activity +and shows a license only when every repository reports the same SPDX license. +It rejects malformed metadata, duplicate repository use and archived +repositories. -* Please search previous suggestions before making a new one, as yours may be a duplicate. -* Please make an individual pull request for each suggestion. -* Use the following format for libraries: \[LIBRARY\]\(LINK\) - DESCRIPTION. -* Entries should be sorted in ascending alphabetical order, i.e. a to z. -* New categories or improvements to the existing categorization are welcome. -* Keep descriptions short, simple and unbiased. -* End all descriptions with a full stop/period. -* Check your spelling and grammar. -* Make sure your text editor is set to remove trailing whitespace. +## License -Thank you for your suggestions! +Catalog and documentation contributions are licensed under +[CC BY-SA 4.0](LICENSE). Automation code and configuration are licensed under +the [MIT License](LICENSE-CODE). By contributing, you agree that your changes +are available under the applicable license. diff --git a/LICENSE b/LICENSE new file mode 100644 index 00000000..795087c2 --- /dev/null +++ b/LICENSE @@ -0,0 +1,427 @@ +Attribution-ShareAlike 4.0 International + +======================================================================= + +Creative Commons Corporation ("Creative Commons") is not a law firm and +does not provide legal services or legal advice. Distribution of +Creative Commons public licenses does not create a lawyer-client or +other relationship. Creative Commons makes its licenses and related +information available on an "as-is" basis. Creative Commons gives no +warranties regarding its licenses, any material licensed under their +terms and conditions, or any related information. Creative Commons +disclaims all liability for damages resulting from their use to the +fullest extent possible. + +Using Creative Commons Public Licenses + +Creative Commons public licenses provide a standard set of terms and +conditions that creators and other rights holders may use to share +original works of authorship and other material subject to copyright +and certain other rights specified in the public license below. The +following considerations are for informational purposes only, are not +exhaustive, and do not form part of our licenses. + + Considerations for licensors: Our public licenses are + intended for use by those authorized to give the public + permission to use material in ways otherwise restricted by + copyright and certain other rights. Our licenses are + irrevocable. Licensors should read and understand the terms + and conditions of the license they choose before applying it. + Licensors should also secure all rights necessary before + applying our licenses so that the public can reuse the + material as expected. Licensors should clearly mark any + material not subject to the license. This includes other CC- + licensed material, or material used under an exception or + limitation to copyright. More considerations for licensors: + wiki.creativecommons.org/Considerations_for_licensors + + Considerations for the public: By using one of our public + licenses, a licensor grants the public permission to use the + licensed material under specified terms and conditions. If + the licensor's permission is not necessary for any reason--for + example, because of any applicable exception or limitation to + copyright--then that use is not regulated by the license. Our + licenses grant only permissions under copyright and certain + other rights that a licensor has authority to grant. Use of + the licensed material may still be restricted for other + reasons, including because others have copyright or other + rights in the material. A licensor may make special requests, + such as asking that all changes be marked or described. + Although not required by our licenses, you are encouraged to + respect those requests where reasonable. More considerations + for the public: + wiki.creativecommons.org/Considerations_for_licensees + +======================================================================= + +Creative Commons Attribution-ShareAlike 4.0 International Public +License + +By exercising the Licensed Rights (defined below), You accept and agree +to be bound by the terms and conditions of this Creative Commons +Attribution-ShareAlike 4.0 International Public License ("Public +License"). To the extent this Public License may be interpreted as a +contract, You are granted the Licensed Rights in consideration of Your +acceptance of these terms and conditions, and the Licensor grants You +such rights in consideration of benefits the Licensor receives from +making the Licensed Material available under these terms and +conditions. + + +Section 1 -- Definitions. + + a. Adapted Material means material subject to Copyright and Similar + Rights that is derived from or based upon the Licensed Material + and in which the Licensed Material is translated, altered, + arranged, transformed, or otherwise modified in a manner requiring + permission under the Copyright and Similar Rights held by the + Licensor. For purposes of this Public License, where the Licensed + Material is a musical work, performance, or sound recording, + Adapted Material is always produced where the Licensed Material is + synched in timed relation with a moving image. + + b. Adapter's License means the license You apply to Your Copyright + and Similar Rights in Your contributions to Adapted Material in + accordance with the terms and conditions of this Public License. + + c. BY-SA Compatible License means a license listed at + creativecommons.org/compatiblelicenses, approved by Creative + Commons as essentially the equivalent of this Public License. + + d. Copyright and Similar Rights means copyright and/or similar rights + closely related to copyright including, without limitation, + performance, broadcast, sound recording, and Sui Generis Database + Rights, without regard to how the rights are labeled or + categorized. For purposes of this Public License, the rights + specified in Section 2(b)(1)-(2) are not Copyright and Similar + Rights. + + e. Effective Technological Measures means those measures that, in the + absence of proper authority, may not be circumvented under laws + fulfilling obligations under Article 11 of the WIPO Copyright + Treaty adopted on December 20, 1996, and/or similar international + agreements. + + f. Exceptions and Limitations means fair use, fair dealing, and/or + any other exception or limitation to Copyright and Similar Rights + that applies to Your use of the Licensed Material. + + g. License Elements means the license attributes listed in the name + of a Creative Commons Public License. The License Elements of this + Public License are Attribution and ShareAlike. + + h. Licensed Material means the artistic or literary work, database, + or other material to which the Licensor applied this Public + License. + + i. Licensed Rights means the rights granted to You subject to the + terms and conditions of this Public License, which are limited to + all Copyright and Similar Rights that apply to Your use of the + Licensed Material and that the Licensor has authority to license. + + j. Licensor means the individual(s) or entity(ies) granting rights + under this Public License. + + k. Share means to provide material to the public by any means or + process that requires permission under the Licensed Rights, such + as reproduction, public display, public performance, distribution, + dissemination, communication, or importation, and to make material + available to the public including in ways that members of the + public may access the material from a place and at a time + individually chosen by them. + + l. Sui Generis Database Rights means rights other than copyright + resulting from Directive 96/9/EC of the European Parliament and of + the Council of 11 March 1996 on the legal protection of databases, + as amended and/or succeeded, as well as other essentially + equivalent rights anywhere in the world. + + m. You means the individual or entity exercising the Licensed Rights + under this Public License. Your has a corresponding meaning. + + +Section 2 -- Scope. + + a. License grant. + + 1. Subject to the terms and conditions of this Public License, + the Licensor hereby grants You a worldwide, royalty-free, + non-sublicensable, non-exclusive, irrevocable license to + exercise the Licensed Rights in the Licensed Material to: + + a. reproduce and Share the Licensed Material, in whole or + in part; and + + b. produce, reproduce, and Share Adapted Material. + + 2. Exceptions and Limitations. For the avoidance of doubt, where + Exceptions and Limitations apply to Your use, this Public + License does not apply, and You do not need to comply with + its terms and conditions. + + 3. Term. The term of this Public License is specified in Section + 6(a). + + 4. Media and formats; technical modifications allowed. The + Licensor authorizes You to exercise the Licensed Rights in + all media and formats whether now known or hereafter created, + and to make technical modifications necessary to do so. The + Licensor waives and/or agrees not to assert any right or + authority to forbid You from making technical modifications + necessary to exercise the Licensed Rights, including + technical modifications necessary to circumvent Effective + Technological Measures. For purposes of this Public License, + simply making modifications authorized by this Section 2(a) + (4) never produces Adapted Material. + + 5. Downstream recipients. + + a. Offer from the Licensor -- Licensed Material. Every + recipient of the Licensed Material automatically + receives an offer from the Licensor to exercise the + Licensed Rights under the terms and conditions of this + Public License. + + b. Additional offer from the Licensor -- Adapted Material. + Every recipient of Adapted Material from You + automatically receives an offer from the Licensor to + exercise the Licensed Rights in the Adapted Material + under the conditions of the Adapter's License You apply. + + c. No downstream restrictions. You may not offer or impose + any additional or different terms or conditions on, or + apply any Effective Technological Measures to, the + Licensed Material if doing so restricts exercise of the + Licensed Rights by any recipient of the Licensed + Material. + + 6. No endorsement. Nothing in this Public License constitutes or + may be construed as permission to assert or imply that You + are, or that Your use of the Licensed Material is, connected + with, or sponsored, endorsed, or granted official status by, + the Licensor or others designated to receive attribution as + provided in Section 3(a)(1)(A)(i). + + b. Other rights. + + 1. Moral rights, such as the right of integrity, are not + licensed under this Public License, nor are publicity, + privacy, and/or other similar personality rights; however, to + the extent possible, the Licensor waives and/or agrees not to + assert any such rights held by the Licensor to the limited + extent necessary to allow You to exercise the Licensed + Rights, but not otherwise. + + 2. Patent and trademark rights are not licensed under this + Public License. + + 3. To the extent possible, the Licensor waives any right to + collect royalties from You for the exercise of the Licensed + Rights, whether directly or through a collecting society + under any voluntary or waivable statutory or compulsory + licensing scheme. In all other cases the Licensor expressly + reserves any right to collect such royalties. + + +Section 3 -- License Conditions. + +Your exercise of the Licensed Rights is expressly made subject to the +following conditions. + + a. Attribution. + + 1. If You Share the Licensed Material (including in modified + form), You must: + + a. retain the following if it is supplied by the Licensor + with the Licensed Material: + + i. identification of the creator(s) of the Licensed + Material and any others designated to receive + attribution, in any reasonable manner requested by + the Licensor (including by pseudonym if + designated); + + ii. a copyright notice; + + iii. a notice that refers to this Public License; + + iv. a notice that refers to the disclaimer of + warranties; + + v. a URI or hyperlink to the Licensed Material to the + extent reasonably practicable; + + b. indicate if You modified the Licensed Material and + retain an indication of any previous modifications; and + + c. indicate the Licensed Material is licensed under this + Public License, and include the text of, or the URI or + hyperlink to, this Public License. + + 2. You may satisfy the conditions in Section 3(a)(1) in any + reasonable manner based on the medium, means, and context in + which You Share the Licensed Material. For example, it may be + reasonable to satisfy the conditions by providing a URI or + hyperlink to a resource that includes the required + information. + + 3. If requested by the Licensor, You must remove any of the + information required by Section 3(a)(1)(A) to the extent + reasonably practicable. + + b. ShareAlike. + + In addition to the conditions in Section 3(a), if You Share + Adapted Material You produce, the following conditions also apply. + + 1. The Adapter's License You apply must be a Creative Commons + license with the same License Elements, this version or + later, or a BY-SA Compatible License. + + 2. You must include the text of, or the URI or hyperlink to, the + Adapter's License You apply. You may satisfy this condition + in any reasonable manner based on the medium, means, and + context in which You Share Adapted Material. + + 3. You may not offer or impose any additional or different terms + or conditions on, or apply any Effective Technological + Measures to, Adapted Material that restrict exercise of the + rights granted under the Adapter's License You apply. + + +Section 4 -- Sui Generis Database Rights. + +Where the Licensed Rights include Sui Generis Database Rights that +apply to Your use of the Licensed Material: + + a. for the avoidance of doubt, Section 2(a)(1) grants You the right + to extract, reuse, reproduce, and Share all or a substantial + portion of the contents of the database; + + b. if You include all or a substantial portion of the database + contents in a database in which You have Sui Generis Database + Rights, then the database in which You have Sui Generis Database + Rights (but not its individual contents) is Adapted Material, + including for purposes of Section 3(b); and + + c. You must comply with the conditions in Section 3(a) if You Share + all or a substantial portion of the contents of the database. + +For the avoidance of doubt, this Section 4 supplements and does not +replace Your obligations under this Public License where the Licensed +Rights include other Copyright and Similar Rights. + + +Section 5 -- Disclaimer of Warranties and Limitation of Liability. + + a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE + EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS + AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF + ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, + IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, + WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR + PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, + ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT + KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT + ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU. + + b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE + TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, + NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, + INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, + COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR + USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN + ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR + DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR + IN PART, THIS LIMITATION MAY NOT APPLY TO YOU. + + c. The disclaimer of warranties and limitation of liability provided + above shall be interpreted in a manner that, to the extent + possible, most closely approximates an absolute disclaimer and + waiver of all liability. + + +Section 6 -- Term and Termination. + + a. This Public License applies for the term of the Copyright and + Similar Rights licensed here. However, if You fail to comply with + this Public License, then Your rights under this Public License + terminate automatically. + + b. Where Your right to use the Licensed Material has terminated under + Section 6(a), it reinstates: + + 1. automatically as of the date the violation is cured, provided + it is cured within 30 days of Your discovery of the + violation; or + + 2. upon express reinstatement by the Licensor. + + For the avoidance of doubt, this Section 6(b) does not affect any + right the Licensor may have to seek remedies for Your violations + of this Public License. + + c. For the avoidance of doubt, the Licensor may also offer the + Licensed Material under separate terms or conditions or stop + distributing the Licensed Material at any time; however, doing so + will not terminate this Public License. + + d. Sections 1, 5, 6, 7, and 8 survive termination of this Public + License. + + +Section 7 -- Other Terms and Conditions. + + a. The Licensor shall not be bound by any additional or different + terms or conditions communicated by You unless expressly agreed. + + b. Any arrangements, understandings, or agreements regarding the + Licensed Material not stated herein are separate from and + independent of the terms and conditions of this Public License. + + +Section 8 -- Interpretation. + + a. For the avoidance of doubt, this Public License does not, and + shall not be interpreted to, reduce, limit, restrict, or impose + conditions on any use of the Licensed Material that could lawfully + be made without permission under this Public License. + + b. To the extent possible, if any provision of this Public License is + deemed unenforceable, it shall be automatically reformed to the + minimum extent necessary to make it enforceable. If the provision + cannot be reformed, it shall be severed from this Public License + without affecting the enforceability of the remaining terms and + conditions. + + c. No term or condition of this Public License will be waived and no + failure to comply consented to unless expressly agreed to by the + Licensor. + + d. Nothing in this Public License constitutes or may be interpreted + as a limitation upon, or waiver of, any privileges and immunities + that apply to the Licensor or You, including from the legal + processes of any jurisdiction or authority. + + +======================================================================= + +Creative Commons is not a party to its public licenses. +Notwithstanding, Creative Commons may elect to apply one of its public +licenses to material it publishes and in those instances will be +considered the β€œLicensor.” The text of the Creative Commons public +licenses is dedicated to the public domain under the CC0 Public Domain +Dedication. Except for the limited purpose of indicating that material +is shared under a Creative Commons public license or as otherwise +permitted by the Creative Commons policies published at +creativecommons.org/policies, Creative Commons does not authorize the +use of the trademark "Creative Commons" or any other trademark or logo +of Creative Commons without its prior written consent including, +without limitation, in connection with any unauthorized modifications +to any of its public licenses or any other arrangements, +understandings, or agreements concerning use of licensed material. For +the avoidance of doubt, this paragraph does not form part of the public +licenses. + +Creative Commons may be contacted at creativecommons.org. diff --git a/LICENSE-CODE b/LICENSE-CODE new file mode 100644 index 00000000..be59e4ee --- /dev/null +++ b/LICENSE-CODE @@ -0,0 +1,21 @@ +MIT License + +Copyright (c) 2026 Andreas Kull + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. diff --git a/LICENSE.md b/LICENSE.md deleted file mode 100644 index 50fdedc0..00000000 --- a/LICENSE.md +++ /dev/null @@ -1 +0,0 @@ -[CC-BY-SA-4.0](https://creativecommons.org/licenses/by-sa/4.0/legalcode) diff --git a/README.md b/README.md index 448dbd86..a3f93389 100644 --- a/README.md +++ b/README.md @@ -1,1097 +1,2474 @@ + + # Awesome Java [![Awesome](https://awesome.re/badge.svg)](https://awesome.re) -A curated list of awesome Java frameworks, libraries and software. - -## Contents - -- [Projects](#projects) - - [Bean Mapping](#bean-mapping) - - [Build](#build) - - [Bytecode Manipulation](#bytecode-manipulation) - - [Caching](#caching) - - [Cluster Management](#cluster-management) - - [Code Analysis](#code-analysis) - - [Code Coverage](#code-coverage) - - [Code Generators](#code-generators) - - [Command-line Argument Parsers](#command-line-argument-parsers) - - [Compiler-compiler](#compiler-compiler) - - [Configuration](#configuration) - - [Constraint Satisfaction Problem Solver](#constraint-satisfaction-problem-solver) - - [CSV](#csv) - - [Data structures](#data-structures) - - [Database](#database) - - [Date and Time](#date-and-time) - - [Dependency Injection](#dependency-injection) - - [Development](#development) - - [Distributed Applications](#distributed-applications) - - [Distributed Transactions](#distributed-transactions) - - [Distribution](#distribution) - - [Document Processing](#document-processing) - - [Formal Verification](#formal-verification) - - [Functional Programming](#functional-programming) - - [Game Development](#game-development) - - [Geospatial](#geospatial) - - [GUI](#gui) - - [High Performance](#high-performance) - - [HTTP Clients](#http-clients) - - [Hypermedia Types](#hypermedia-types) - - [IDE](#ide) - - [Imagery](#imagery) - - [JSON Processing](#json-processing) - - [JSON](#json) - - [JVM and JDK](#jvm-and-jdk) - - [Logging](#logging) - - [Machine Learning](#machine-learning) - - [Messaging](#messaging) - - [Microservice](#microservice) - - [Miscellaneous](#miscellaneous) - - [Monitoring](#monitoring) - - [Native](#native) - - [Natural Language Processing](#natural-language-processing) - - [Networking](#networking) - - [ORM](#orm) - - [PaaS](#paas) - - [PDF](#pdf) - - [Performance analysis](#performance-analysis) - - [Platform](#platform) - - [Reactive libraries](#reactive-libraries) - - [REST Frameworks](#rest-frameworks) - - [Science](#science) - - [Search](#search) - - [Security](#security) - - [Serialization](#serialization) - - [Server](#server) - - [Template Engine](#template-engine) - - [Testing](#testing) - - [Utility](#utility) - - [Version Managers](#version-managers) - - [Web Crawling](#web-crawling) - - [Web Frameworks](#web-frameworks) -- [Resources](#resources) - - [Awesome Lists](#awesome-lists) - - [Communities](#communities) - - [Frontends](#frontends) - - [Influential Books](#influential-books) - - [Podcasts and Screencasts](#podcasts-and-screencasts) - - [Twitter](#twitter) - - [Websites](#websites) -- [Contributing](#contributing) +A curated list of noteworthy Java frameworks, libraries, tools and resources. + +811 projects Β· 80 categories Β· 85 resources + +Activity: 🟒 pushed within 3 months Β· 🟠 pushed 3–12 months ago Β· πŸ”΄ no push for over 12 months + +License chips use GitHub SPDX metadata when available. + +Entries spanning several repositories combine their stars, use the most recent push for activity and show a license only when all repositories agree. ## Projects -### Bean Mapping +
+Architecture 4 projects -*Frameworks that ease bean mapping.* +_Frameworks and libraries that help implementing and verifying design and architecture concepts._ -- [Dozer](https://github.com/DozerMapper/dozer) - Mapper that copies data from one object to another using annotations and API or XML configuration. -- [JMapper](https://jmapper-framework.github.io/jmapper-core) - Uses byte code manipulation for lightning-fast mapping. Supports annotations and API or XML configuration. -- [MapStruct](https://github.com/mapstruct/mapstruct) - Code generator that simplifies mappings between different bean types, based on a convention-over-configuration approach. -- [ModelMapper](https://github.com/jhalterman/modelmapper) - Intelligent object mapping library that automatically maps objects to each other. -- [Orika](https://github.com/orika-mapper/orika) - JavaBean-mapping framework that recursively copies (among other capabilities) data from one object to another. -- [Selma](https://github.com/xebia-france/selma) - Annotation processor-based bean mapper. +> **[ArchUnit](https://github.com/TNG/ArchUnit)** β˜… 3.8k Apache-2.0 🟒
Test library for specifying and asserting architecture rules. -### Build +> **[jMolecules](https://github.com/xmolecules/jmolecules)** β˜… 1.5k Apache-2.0 🟠
Annotations and interfaces to express design and architecture concepts in code. -*Tools that handle the build cycle and dependencies of an application.* +> **[jQAssistant](https://github.com/jQAssistant/jqassistant)** β˜… 285 GPL-3.0 🟒
Static code analysis with Neo4J-based query language. -- [Apache Maven](https://maven.apache.org) - Declarative build and dependency management that favors convention over configuration. It might be preferable to Apache Ant, which uses a rather procedural approach and can be difficult to maintain. -- [Bazel](https://bazel.io) - Tool from Google that builds code quickly and reliably. -- [Buck](https://github.com/facebook/buck) - Encourages the creation of small, reusable modules consisting of code and resources. -- [Gradle](https://gradle.org) - Incremental builds programmed via Groovy instead of declaring XML. Works well with Maven's dependency management. +> **[Taikai](https://github.com/enofex/taikai)** β˜… 244 MIT 🟒
ArchUnit extension with predefined architecture rules for common Java technologies. -### Bytecode Manipulation +
-*Libraries to manipulate bytecode programmatically.* +
+Artificial Intelligence 15 projects -- [ASM](http://asm.ow2.org) - All-purpose, low-level bytecode manipulation and analysis. -- [Byte Buddy](http://bytebuddy.net) - Further simplifies bytecode generation with a fluent API. -- [bytecode-viewer](https://github.com/Konloch/bytecode-viewer) - Java 8 Jar & Android APK reverse engineering suite. -- [Byteman](https://byteman.jboss.org) - Manipulate bytecode at runtime via DSL (rules); mainly for testing/troubleshooting. -- [cglib](https://github.com/cglib/cglib) - Bytecode generation library. -- [Javassist](https://jboss-javassist.github.io/javassist) - Tries to simplify bytecode editing. +_Frameworks for building applications with AI, agents and knowledge-based systems._ -### Caching +> **[A2A Java SDK](https://github.com/a2aproject/a2a-java)** β˜… 467 Apache-2.0 🟒
Official Java SDK for the Agent2Agent protocol. -*Libraries that provide caching facilities.* +> **[AgentScope Java](https://github.com/agentscope-ai/agentscope-java)** β˜… 4.8k 🟒
Framework for building distributed, long-running AI agents with tool execution, persistence and multi-agent orchestration. -- [Caffeine](https://github.com/ben-manes/caffeine) - High-performance, near-optimal caching library. -- [Ehcache](http://www.ehcache.org) - Distributed general-purpose cache. -- [Infinispan](http://infinispan.org) - Highly concurrent key/value datastore used for caching. +> **[Anahata ASI](https://github.com/anahata-os/anahata-asi)** β˜… 23 Apache-2.0 🟒
Java agent container with local LLM adapters, stateful tool execution, context management and IDE integration. -### Cluster Management +> **[Dokimos](https://github.com/dokimos-dev/dokimos)** β˜… 48 MIT 🟒
Evaluation framework for LLM and AI-agent applications that scores responses, validates tool calls and execution traces, and catches quality regressions in CI. -*Frameworks that can dynamically manage applications inside of a cluster.* +> **[Google Gen AI Java SDK](https://github.com/googleapis/java-genai)** β˜… 385 Apache-2.0 🟒
Official Java SDK for integrating Google generative AI models. -- [Apache Aurora](https://aurora.apache.org) - Mesos framework for long-running services and cron jobs. -- [Apache Mesos](https://mesos.apache.org) - Abstracts CPU, memory, storage, and other compute resources away from machines. -- [Singularity](http://getsingularity.com) - Mesos framework that makes deployment and operations easy. It supports web services, background workers, scheduled jobs, and one-off tasks. +> **[JADE](https://jade.tilab.com)**
Framework and environment for building and debugging multi-agent systems. (LGPL-2.0-only) -### Code Analysis +> **[JamJet](https://github.com/jamjet-labs/jamjet)** β˜… 19 Apache-2.0 🟒
Agent runtime with a Java SDK for building AI agents, supporting graph-based workflow orchestration, multi-agent coordination, and MCP/A2A protocols. -*Tools that provide metrics and quality measurements.* +> **[LangChain4j](https://github.com/langchain4j/langchain4j)** β˜… 12.8k Apache-2.0 🟒
Simplifies integration of LLMs with unified APIs and a comprehensive toolbox. -- [Checkstyle](https://github.com/checkstyle/checkstyle) - Static analysis of coding conventions and standards. -- [Error Prone](https://github.com/google/error-prone) - Catches common programming mistakes as compile-time errors. -- [Infer](https://github.com/facebook/infer) - Modern static analysis tool for verifying the correctness of code. -- [jQAssistant](https://jqassistant.org) - Static code analysis with Neo4J-based query language. -- [NullAway](https://github.com/uber/NullAway) - Eliminates NullPointerExceptions with low build-time overhead. -- [PMD](https://github.com/pmd/pmd) - Source code analysis for finding bad coding practices. -- [SonarJava](https://github.com/SonarSource/sonar-java) - Static analyzer for SonarQube & SonarLint. -- [Sourcetrail ![c]](https://www.sourcetrail.com) - Visual source code navigator. -- [Spoon](https://github.com/INRIA/spoon) - Library for analyzing and transforming Java source code. -- [Spotbugs](https://github.com/spotbugs/spotbugs) - Static analysis of bytecode to find potential bugs. +> **[liter-llm](https://github.com/xberg-io/liter-llm)** β˜… 240 MIT 🟒
Provides a Java binding for a unified LLM API client across multiple providers. -### Code Coverage +> **[MCP Java SDK](https://github.com/modelcontextprotocol/java-sdk)** β˜… 3.6k MIT 🟒
Enables applications to interact with AI models and tools through a standardized interface (i.e. Model Context Protocol), supporting both synchronous and asynchronous communication patterns. -*Frameworks and tools that enable code coverage metrics collection for test suites.* +> **[ProtΓ©gΓ©](https://github.com/protegeproject/protege)** β˜… 1.4k 🟠
Provides an ontology editor and a framework to build knowledge-based systems. -- [Clover ![c]](https://www.atlassian.com/software/clover/overview) - Relies on source-code instrumentation instead of bytecode instrumentation. -- [Cobertura](https://cobertura.github.io/cobertura) - Relies on offline (or static) bytecode instrumentation and class loading to collect code coverage metrics. -- [JaCoCo](http://eclemma.org/jacoco) - Framework that enables collection of code coverage metrics, using both offline and runtime bytecode instrumentation. +> **[Regulus](https://github.com/neul-labs/regulus)** β˜… 6 MIT 🟒
Google ADK plugin suite that adds runtime compliance profiles, audit envelopes and GRC adapters for regulated Java AI agents. -### Code Generators +> **[simple-openai](https://github.com/sashirestela/simple-openai)** β˜… 380 MIT 🟠
Library to use the OpenAI API (and compatible ones) in the simplest possible way. -*Tools that generate patterns for repetitive code in order to reduce verbosity and error-proneness.* +> **[Spring AI](https://github.com/spring-projects/spring-ai)** β˜… 9.2k Apache-2.0 🟒
Application framework for AI engineering for Spring. -- [ADT4J](https://github.com/sviperll/adt4j) - JSR-269 code generator for algebraic data types. -- [Auto](https://github.com/google/auto) - Generates factory, service, and value classes. -- [FreeBuilder](https://github.com/google/FreeBuilder) - Automatically generates the Builder pattern. -- [Immutables](https://immutables.github.io) - Annotation processors to generate simple, safe and consistent value objects. -- [JavaPoet](https://github.com/square/javapoet) - API to generate source files. -- [JHipster](https://github.com/jhipster/generator-jhipster) - Yeoman source code generator for Spring Boot and AngularJS. -- [Joda-Beans](http://www.joda.org/joda-beans) - Small framework that adds queryable properties to Java, enhancing JavaBeans. -- [Lombok](https://projectlombok.org) - Code generator that aims to reduce verbosity. +> **[Spring AI Alibaba](https://github.com/alibaba/spring-ai-alibaba)** β˜… 10.5k Apache-2.0 🟒
Agentic AI framework built on Spring AI with model, tool, RAG and workflow integrations. -### Command-line Argument Parsers +
-*Libraries that make it easy to parse command line options, arguments, etc.* +
+Bean Mapping 4 projects -- [Airline](https://github.com/airlift/airline) - Annotation-based framework for parsing Git-like command-line arguments. -- [args4j](http://args4j.kohsuke.org) - Small library to parse command-line arguments. -- [JCommander](http://jcommander.org) - Command-line argument-parsing framework with custom types and validation via implementing interfaces. -- [JOpt Simple](https://pholser.github.io/jopt-simple) - Simple parser that uses the POSIX getopt() and GNU getopt_long() syntaxes. Uses a fluent API instead of annotations. -- [picocli](http://picocli.info) - ANSI colors and styles in usage help. Can be included as source to avoid dependency. Annotation-based, POSIX/GNU/any syntax, subcommands, strong typing for both options and positional args. +_Frameworks that ease bean mapping._ -### Compiler-compiler +> **[Immuto](https://github.com/karunarathnad/immuto)** β˜… 6 🟒
Annotation processor that generates type-safe mapper implementations for Java Records using canonical constructors, with zero runtime reflection. -*Frameworks that help to create parsers, interpreters or compilers.* +> **[MapStruct](https://github.com/mapstruct/mapstruct)** β˜… 7.7k 🟒
Code generator that simplifies mappings between different bean types, based on a convention-over-configuration approach. -- [ANTLR](http://www.antlr.org) - Complex full-featured framework for top-down parsing. -- [JavaCC](https://javacc.org) - Parser generator that generates top-down parsers. Allows lexical state switching and permits extended BNF specifications. -- [JFlex](http://jflex.de) - A lexical analyzer generator. +> **[ModelMapper](https://github.com/modelmapper/modelmapper)** β˜… 2.4k Apache-2.0 🟠
Intelligent object mapping library that automatically maps objects to each other. -### Configuration +> **[reMap](https://github.com/remondis-it/remap)** β˜… 128 Apache-2.0 🟒
Lambda and method handle-based mapping which requires code and not annotations if objects have different names. -*Libraries that provide external configuration.* +
-- [centraldogma](https://github.com/line/centraldogma) - Highly-available version-controlled service configuration repository based on Git, ZooKeeper and HTTP/2. -- [cfg4j](https://github.com/cfg4j/cfg4j) - Modern configuration library for distributed apps written in Java. -- [config](https://github.com/typesafehub/config) - Configuration library for JVM languages. -- [dotenv](https://github.com/shyiko/dotenv) - A twelve-factor configuration library for Java. -- [ini4j](http://ini4j.sourceforge.net) - Provides an API for handling Windows' INI files. -- [KAConf](https://github.com/mariomac/kaconf) - Annotation-based configuration system for Java and Kotlin. -- [owner](https://github.com/lviggiano/owner) - Reduces boilerplate of properties. +
+Bot Development 4 projects -### Constraint Satisfaction Problem Solver +_Libraries and frameworks for building chatbots and messaging-platform bots._ -*Libraries that help with implementing optimization and satisfiability problems.* +> **[JBot](https://github.com/rampatra/jbot)** β˜… 1.2k GPL-3.0 🟠
Framework for building chatbots. -- [Choco](http://choco-solver.org) - Off-the-shelf constraint satisfaction problem solver that uses constraint programming techniques. -- [JaCoP](https://github.com/radsz/jacop) - Includes an interface for the FlatZinc language, enabling it to execute MiniZinc models. -- [OptaPlanner](https://www.optaplanner.org) - Business planning and resource scheduling optimization solver. +> **[JDA](https://github.com/discord-jda/JDA)** β˜… 4.7k Apache-2.0 🟒
Wrapping of the Discord REST API and its WebSocket events. -### CSV - -*Frameworks and libraries that simplify reading/writing CSV data.* - -- [jackson-dataformat-csv](https://github.com/FasterXML/jackson-dataformat-csv) - Jackson extension for reading and writing CSV. -- [opencsv](http://opencsv.sourceforge.net) - Simple CSV parser. -- [Super CSV](https://super-csv.github.io/super-csv) - Powerful CSV parser with support for Dozer, Joda-Time and Java 8. -- [uniVocity-parsers](https://github.com/uniVocity/univocity-parsers) - One of the fastest and most feature-complete parsers. Also comes with parsers for TSV and fixed-width records. - -### Database - -*Everything that simplifies interactions with the database.* - -- [Apache Phoenix](https://phoenix.apache.org) - High-performance relational database layer over HBase for low-latency applications. -- [Chronicle Map](https://github.com/OpenHFT/Chronicle-Map) - Efficient, in-memory (opt. persisted to disk), off-heap key-value store. -- [druid](http://druid.io) - High-performance, column-oriented, distributed data store. -- [eXist](https://github.com/eXist-db/exist) - A NoSQL document database and application platform. -- [FlexyPool](https://github.com/vladmihalcea/flexy-pool) - Brings metrics and failover strategies to the most common connection pooling solutions. -- [Flyway](https://flywaydb.org) - Simple database migration tool. -- [H2](https://h2database.com) - Small SQL database notable for its in-memory functionality. -- [HikariCP](https://github.com/brettwooldridge/HikariCP) - High-performance JDBC connection pool. -- [JDBI](http://jdbi.org) - Convenient abstraction of JDBC. -- [Jedis](https://github.com/xetorthio/jedis) - Small client for interaction with Redis, with methods for commands. -- [Jest](https://github.com/searchbox-io/Jest) - Client for the Elasticsearch REST API. -- [jetcd](https://github.com/justinsb/jetcd) - Client library for etcd. -- [Jinq](https://github.com/my2iu/Jinq) - Typesafe database queries via symbolic execution of Java 8 Lambdas (on top of JPA or jOOQ). -- [jOOQ](https://www.jooq.org) - Generates typesafe code based on SQL schema. -- [Liquibase](http://www.liquibase.org) - Database-independent library for tracking, managing and applying database schema changes. -- [MapDB](http://www.mapdb.org) - Embedded database engine that provides concurrent collections backed on disk or in off-heap memory. -- [MariaDB4j](https://github.com/vorburger/MariaDB4j) - Launcher for MariaDB that requires no installation or external dependencies. -- [OrientDB](https://orientdb.com/orientdb) - Embeddable distributed database written on top of Hazelcast. -- [Presto](https://github.com/prestodb/presto) - Distributed SQL query engine for big data. -- [Querydsl](http://www.querydsl.com) - Typesafe unified queries. -- [Realm](https://github.com/realm/realm-java) - Mobile database to run directly inside phones, tablets or wearables. -- [Redisson](https://github.com/mrniko/redisson) - Allows for distributed and scalable data structures on top of a Redis server. -- [requery](https://github.com/requery/requery) - A modern, lightweight but powerful object mapping and SQL generator. Easily map to or create databases, or perform queries and updates from any Java-using platform. -- [Speedment](https://github.com/speedment/speedment) - Database access library that utilizes Java 8's Stream API for querying. -- [sql2o](https://sql2o.org) - Thin JDBC wrapper that simplifies database access and provides simple mapping of ResultSets to POJOs. -- [Vibur DBCP](https://www.vibur.org) - JDBC connection pool library with advanced performance monitoring capabilities. -- [Xodus](https://jetbrains.github.io/xodus) - Highly concurrent transactional schema-less and ACID-compliant embedded database. - -### Data Structures - -*Efficient and specific data structures.* - -- [Apache Avro](https://avro.apache.org) - Data interchange format with dynamic typing, untagged data, and absence of manually assigned IDs. -- [Apache Orc](https://orc.apache.org) - Fast and efficient columnar storage format for Hadoop-based workloads. -- [Apache Parquet](https://parquet.apache.org) - Columnar storage format based on assembly algorithms from Google's paper on Dremel. -- [Apache Thrift](https://thrift.apache.org) - Data interchange format that originated at Facebook. -- [Big Queue](https://github.com/bulldog2011/bigqueue) - A big, fast and persistent queue based on memory-mapped files. -- [Persistent Collection](https://pcollections.org) - Persistent and immutable analogue of the Java Collections Framework. -- [Protobuf](https://github.com/google/protobuf) - Google's data interchange format. -- [SBE](https://github.com/real-logic/simple-binary-encoding) - Simple Binary Encoding, one of the fastest message formats around. -- [Tape](https://github.com/square/tape) - A lightning-fast, transactional, file-based FIFO. -- [Wire](https://github.com/square/wire) - Clean, lightweight protocol buffers. - -### Date and Time - -*Libraries related to handling date and time.* - -- [Almanac Converter](https://github.com/hypotemoose/almanac-converter) - Simple conversion between different calendar systems. -- [iCal4j](https://github.com/ical4j/ical4j) - Parse and build iCalendar [RFC 5545](https://tools.ietf.org/html/rfc5545) data models. -- [ThreeTen-Extra](https://github.com/ThreeTen/threeten-extra) - Additional date-time classes that complement those in JDK 8. -- [Time4J](https://github.com/MenoData/Time4J) - Advanced date and time library. - -### Dependency Injection - -*Libraries that help to realize the [Inversion of Control](https://en.wikipedia.org/wiki/Inversion_of_control) paradigm.* - -- [Apache DeltaSpike](https://deltaspike.apache.org) - CDI extension framework. -- [Dagger2](https://google.github.io/dagger) - Compile-time injection framework without reflection. -- [Feather](https://github.com/zsoltherpai/feather) - Ultra-lightweight, JSR-330-compliant dependency injection library. -- [Governator](https://github.com/Netflix/governator) - Extensions and utilities that enhance Google Guice. -- [Guice](https://github.com/google/guice) - Lightweight and opinionated framework that completes Dagger. -- [HK2](https://javaee.github.io/hk2) - Lightweight and dynamic dependency injection framework. - -### Development - -*Augmentation of the development process at a fundamental level.* - -- [AspectJ](https://eclipse.org/aspectj) - Seamless aspect-oriented programming extension. -- [DCEVM](https://dcevm.github.io) - JVM modification that allows unlimited redefinition of loaded classes at runtime. -- [Faux Pas](https://github.com/zalando/faux-pas) - Library that simplifies error handling by circumventing the issue that none of the functional interfaces in the Java Runtime is allowed by default to throw checked exceptions. -- [HotswapAgent](https://github.com/HotswapProjects/HotswapAgent) - Unlimited runtime class and resource redefinition. -- [JavaParser](https://github.com/javaparser/javaparser) - Parse, modify and generate Java code. -- [JavaSymbolSolver](https://github.com/javaparser/javasymbolsolver) - A symbol solver for Java. -- [JRebel ![c]](https://zeroturnaround.com/software/jrebel) - Instantly reloads code and configuration changes without redeploys. -- [NoException](https://noexception.machinezoo.com) - Allows checked exceptions in functional interfaces and converts exceptions to Optional return. - -### Distributed Applications - -*Libraries and frameworks for writing distributed and fault-tolerant applications.* - -- [Apache Geode](https://geode.apache.org) - In-memory data management system that provides reliable asynchronous event notifications and guaranteed message delivery. -- [Apache Storm](https://storm.apache.org) - Realtime computation system. -- [Apache ZooKeeper](https://zookeeper.apache.org) - Coordination service with distributed configuration, synchronization, and naming registry for large distributed systems. -- [Atomix](http://atomix.io/atomix) - Fault-tolerant distributed coordination framework. -- [Axon Framework](http://www.axonframework.org) - Framework for creating CQRS applications. -- [Copycat](http://atomix.io/copycat) - Fault-tolerant state machine replication framework. -- [Dropwizard Circuit Breaker](https://github.com/mtakaki/dropwizard-circuitbreaker) - Circuit breaker design pattern for Dropwizard. -- [Failsafe](https://github.com/jhalterman/failsafe) - Simple failure handling with retries and circuit breakers. -- [Hazelcast ![c]](https://hazelcast.org) - Highly scalable in-memory datagrid with a free open-source version. -- [Hystrix](https://github.com/Netflix/Hystrix) - Provides latency and fault tolerance. -- [JGroups](http://www.jgroups.org) - Toolkit for reliable messaging and cluster creation. -- [Orbit](http://www.orbit.cloud) - Virtual actors; adds another level of abstraction to traditional actors. -- [Quasar](https://www.paralleluniverse.co/quasar) - Lightweight threads and actors for the JVM. -- [resilience4j](https://github.com/resilience4j/resilience4j) - Functional fault tolerance library. -- [ScaleCube](https://github.com/scalecube/scalecube) - Embeddable Cluster-Membership library based on SWIM and gossip protocol. -- [Zuul](https://github.com/Netflix/zuul) - A gateway service that provides dynamic routing, monitoring, resiliency, security, and more. - -### Distributed Transactions - -*Distributed transactions provide a mechanism for ensuring consistency of data updates in the presence of concurrent access and partial failures.* - -- [Atomikos](https://www.atomikos.com) - Provides transactions for REST, SOA and microservices with support for JTA and XA. -- [Bitronix](https://github.com/bitronix/btm) - A simple but complete implementation of the JTA 1.1 API. -- [Narayana](http://narayana.io) - Provides support for traditional ACID and compensation transactions, also complies with JTA, JTS and other standards. - -### Distribution - -*Tools that handle the distribution of applications in native formats.* - -- [Bintray ![c]](https://bintray.com) - Version control for binaries that handle publishing. Compatible with Maven or Gradle, with a free plan for open-source software as well as several business plans. -- [Boxfuse](https://boxfuse.com) - Deployment of JVM applications to AWS using the principles of immutable infrastructure. -- [Capsule](http://www.capsule.io) - Simple and powerful packaging and deployment. A fat JAR on steroids, or a "Docker for Java" that supports JVM-optimized containers. -- [Central Repository](https://search.maven.org) - Largest binary component repository available as a free service to the open-source community. Default used by Apache Maven, and available in all other build tools. -- [IzPack](http://izpack.org) - Setup authoring tool for cross-platform deployments. -- [JitPack](https://jitpack.io) - Easy-to-use package repository for GitHub. Builds Maven/Gradle projects on demand and publishes ready-to-use packages. -- [Nexus ![c]](https://www.sonatype.com/nexus/solution-overview) - Binary management with proxy and caching capabilities. -- [packr](https://github.com/libgdx/packr) - Packs JARs, assets and the JVM for native distribution on Windows, Linux and Mac OS X. -- [really-executable-jars-maven-plugin](https://github.com/brianm/really-executable-jars-maven-plugin) - Maven plugin for making self-executing JARs. +> **[Nyagram](https://github.com/kaleert/nyagram)** β˜… 8 MIT 🟒
Reactive, type-safe framework for Telegram bots based on Spring Boot 3 and Java 21. -### Document Processing +> **[TelegramBots](https://github.com/rubenlagus/TelegramBots)** β˜… 5.5k MIT 🟒
Java library for building bots with the Telegram Bot API. -*Libraries that assist with processing office document formats.* +
-- [Apache POI](https://poi.apache.org) - Supports OOXML (XLSX, DOCX, PPTX) as well as OLE2 (XLS, DOC or PPT). -- [documents4j](http://documents4j.com) - API for document format conversion using third-party converters such as MS Word. -- [docx4j](https://www.docx4java.org/trac/docx4j) - Create and manipulate Microsoft Open XML files. +
+Build 16 projects -### Formal Verification +_Tools that handle the build cycle and dependencies of an application._ -*Formal-methods tools: proof assistants, model checking, symbolic execution, etc.* +> **[Apache Maven](https://github.com/apache/maven)** β˜… 5.3k Apache-2.0 🟒
Declarative build and dependency management that favors convention over configuration. It might be preferable to Apache Ant, which uses a rather procedural approach and can be difficult to maintain. -- [CATG](https://github.com/ksen007/janala2) - Concolic unit testing engine. Automatically generates unit tests using formal methods. -- [Checker Framework](https://types.cs.washington.edu/checker-framework) - Pluggable type systems. Includes nullness types, physical units, immutability types and more. -- [Daikon](https://plse.cs.washington.edu/daikon) - Detects likely program invariants and generates JML specs based on those invariants. -- [Java Path Finder (JPF)](https://babelfish.arc.nasa.gov/trac/jpf) - JVM formal verification tool containing a model checker and more. Created by NASA. -- [JMLOK 2.0](http://massoni.computacao.ufcg.edu.br/home/jmlok) - Detects inconsistencies between code and JML specification through feedback-directed random tests generation, and suggests a likely cause for each nonconformance detected. -- [KeY](https://key-project.org) - Formal software development tool that aims to integrate design, implementation, formal specification, and formal verification of object-oriented software as seamlessly as possible. Uses JML for specification and symbolic execution for verification. -- [OpenJML](https://openjml.github.io) - Translates JML specifications into SMT-LIB format and passes the proof problems implied by the program to backend solvers. +> **[Bazel](https://github.com/bazelbuild/bazel)** β˜… 25.7k Apache-2.0 🟒
Tool from Google that builds code quickly and reliably. -### Functional Programming +> **[Buck2](https://github.com/facebook/buck2)** β˜… 4.4k Apache-2.0 🟒
Encourages the creation of small, reusable modules consisting of code and resources. -*Libraries that facilitate functional programming.* +> **[Dependency Analysis Gradle Plugin](https://github.com/autonomousapps/dependency-analysis-gradle-plugin)** β˜… 2.2k Apache-2.0 🟒
Analyzes JVM and Android builds and recommends dependency and plugin changes. -- [cyclops-react](https://github.com/aol/cyclops-react) - Monad and stream utilities, comprehensions, pattern matching, functional extensions for all JDK collections, future streams, trampolines and much more. -- [derive4j](https://github.com/derive4j/derive4j) - Java 8 annotation processor and framework for deriving algebraic data types constructors, pattern-matching and morphisms. -- [Fugue](https://bitbucket.org/atlassian/fugue) - Functional extensions to Guava. -- [Functional Java](http://www.functionaljava.org) - Implements numerous basic and advanced programming abstractions that assist composition-oriented development. -- [jOOΞ»](https://github.com/jOOQ/jOOL) - Extension to Java 8 that aims to fix gaps in lambda by providing numerous missing types and a rich set of sequential Stream API additions. -- [protonpack](https://github.com/poetix/protonpack) - Collection of stream utilities. -- [StreamEx](https://github.com/amaembo/streamex) - Enhances Java 8 Streams. -- [Vavr](http://www.vavr.io) - Functional component library that provides persistent data types and functional control structures. +> **[Docker Maven Plugin](https://github.com/fabric8io/docker-maven-plugin)** β˜… 1.9k Apache-2.0 🟒
Builds and runs Docker images from Maven. -### Game Development +> **[Eclipse JKube](https://github.com/eclipse-jkube/jkube)** β˜… 850 EPL-2.0 🟒
Maven and Gradle plugins for building and deploying Java applications on Kubernetes. -*Frameworks that support the development of games.* +> **[Frontend Maven Plugin](https://github.com/eirslett/frontend-maven-plugin)** β˜… 4.4k Apache-2.0 🟒
Installs and runs Node.js frontend tooling from Maven builds. -- [FXGL](https://almasb.github.io/FXGL) - JavaFX Game Development Framework. -- [jMonkeyEngine](http://jmonkeyengine.org) - Game engine for modern 3D development. -- [libGDX](https://libgdx.badlogicgames.com) - All-round cross-platform, high-level framework. -- [LWJGL](https://www.lwjgl.org) - Robust framework that abstracts libraries like OpenGL/CL/AL. +> **[git-commit-id Maven Plugin](https://github.com/git-commit-id/git-commit-id-maven-plugin)** β˜… 1.7k LGPL-3.0 🟒
Exposes Git revision information to Maven builds and applications. -### Geospatial +> **[Gradle](https://github.com/gradle/gradle)** β˜… 18.7k Apache-2.0 🟒
Incremental builds programmed via Groovy instead of declaring XML. Works well with Maven's dependency management. -*Libraries for working with geospatial data and algorithms.* +> **[jar-cart](https://github.com/Sudhanshu-Ambastha/jar-cart)** β˜… 4 MIT 🟒
A modern, zero-configuration package manager and runner for the Java ecosystem written in Go, focusing on developer productivity and build speed. -- [Apache SIS](https://sis.apache.org) - Library for developing geospatial applications. -- [Geo](https://github.com/davidmoten/geo) - GeoHash utilities in Java. -- [Geotoolkit.org](http://www.geotoolkit.org) - Library for developing geospatial applications. Built on top of the Apache SIS project. -- [GeoTools](http://geotools.org) - Library that provides tools for geospatial data. -- [GraphHopper](https://github.com/graphhopper/graphhopper) - Road-routing engine. Used as a Java library or standalone web service. -- [H2GIS](http://www.h2gis.org) - A spatial extension of the H2 database. -- [Jgeohash](https://astrapi69.github.io/jgeohash) - Library for using the GeoHash algorithm. -- [Mapsforge](https://github.com/mapsforge/mapsforge) - Map rendering based on OpenStreetMap data. -- [Spatial4j](https://github.com/locationtech/spatial4j) - General-purpose spatial/geospatial library. +> **[Javadoc Publisher](https://github.com/MathieuSoysal/Javadoc-publisher.yml)** β˜… 57 Apache-2.0 🟠
Generate Javadoc from your maven/gradle project and deploy it automatically on GitHub Page. -### GUI +> **[Jib](https://github.com/GoogleContainerTools/jib)** β˜… 14.4k Apache-2.0 🟒
Builds optimized container images for Java applications without a Docker daemon. -*Libraries to create modern graphical user interfaces.* +> **[Maven Wrapper](https://github.com/apache/maven-wrapper)** β˜… 252 Apache-2.0 🟒
Analogue of Gradle Wrapper for Maven, allowing projects to build without a preinstalled Maven. -- [JavaFX](https://www.oracle.com/technetwork/java/javase/overview/javafx-overview-2158620.html) - The successor of Swing. -- [Scene Builder](https://gluonhq.com/open-source/scene-builder) - Visual layout tool for JavaFX applications. -- [SWT](https://www.eclipse.org/swt) - The Standard Widget Toolkit, a graphical widget toolkit. +> **[Polyglot for Maven](https://github.com/takari/polyglot-maven)** β˜… 922 EPL-1.0 🟒
Extensions for Maven 3.3.1+ that allows writing the POM model in dialects other than XML. -### High Performance +> **[ReleaseRun](https://github.com/Releaserun/releaserun-cli)** β˜… 1 MIT 🟠
Dependency health checker for pom.xml and Gradle projects that scans for CVEs and outdated packages. -*Everything about high-performance computation, from collections to specific libraries.* +> **[Shadow](https://github.com/GradleUp/shadow)** β˜… 4.2k Apache-2.0 🟒
Gradle plugin for creating and transforming executable fat JARs. -- [Agrona](https://github.com/real-logic/Agrona) - Data structures and utility methods that are common in high-performance applications. -- [Disruptor](https://lmax-exchange.github.io/disruptor) - Inter-thread messaging library. -- [Eclipse Collections](https://github.com/eclipse/eclipse-collections) - Collections framework inspired by Smalltalk. -- [fastutil](http://fastutil.di.unimi.it) - Fast and compact type-specific collections. -- [HPPC](https://labs.carrotsearch.com/hppc.html) - Primitive collections. -- [JCTools](https://github.com/JCTools/JCTools) - Concurrency tools currently missing from the JDK. -- [Koloboke](https://github.com/OpenHFT/Koloboke) - Hash sets and hash maps. +
-### HTTP Clients +
+Bytecode Manipulation 7 projects -*Libraries that assist with creating HTTP requests and/or binding responses.* +_Libraries to manipulate bytecode programmatically._ -- [Async Http Client](https://github.com/AsyncHttpClient/async-http-client) - Asynchronous HTTP and WebSocket client library. -- [Feign](https://github.com/Netflix/feign) - HTTP client binder inspired by Retrofit, JAXRS-2.0, and WebSocket. -- [OkHttp](https://square.github.io/okhttp) - HTTP+SPDY client. -- [restQL-core](https://github.com/B2W-BIT/restQL-core) - Microservice query language that fetches information from multiple services. -- [Retrofit](https://square.github.io/retrofit) - Typesafe REST client. -- [Ribbon](https://github.com/Netflix/ribbon) - Client-side IPC library that is battle-tested in cloud. -- [Riptide](https://github.com/zalando/riptide) - Client-side response routing for Spring's RestTemplate. +> **[ASM](https://asm.ow2.io)**
All-purpose, low-level bytecode manipulation and analysis. -### Hypermedia Types +> **[Byte Buddy](https://github.com/raphw/byte-buddy)** β˜… 6.9k Apache-2.0 🟒
Further simplifies bytecode generation with a fluent API. -*Libraries that handle serialization to hypermedia types.* +> **[bytecode-viewer](https://github.com/Konloch/bytecode-viewer)** β˜… 15.6k GPL-3.0 🟒
Java 8 Jar & Android APK reverse engineering suite. -- [JSON-LD](https://github.com/jsonld-java/jsonld-java) - JSON-LD implementation. -- [Siren4J](https://github.com/eserating/siren4j) - Library for the Siren specification. +> **[Byteman](https://github.com/bytemanproject/byteman)** β˜… 514 🟒
Manipulate bytecode at runtime via DSL (rules); mainly for testing/troubleshooting. (LGPL-2.1-or-later) -### IDE +> **[Javassist](https://github.com/jboss-javassist/javassist)** β˜… 4.2k 🟒
Tries to simplify bytecode editing. -*Integrated development environments that try to simplify several aspects of development.* +> **[Maker](https://github.com/cojen/maker)** β˜… 72 Apache-2.0 🟒
Provides low level bytecode generation. -- [Eclipse](https://www.eclipse.org) - Established open-source project with support for lots of plugins and languages. -- [IntelliJ IDEA ![c]](https://www.jetbrains.com/idea) - Supports many JVM languages and provides good options for Android development. The commercial edition targets the enterprise sector. -- [NetBeans](https://netbeans.org) - Provides integration for several Java SE and EE features, from database access to HTML5. -- [Visual Studio Code](https://code.visualstudio.com/docs/languages/java) - Provides Java support for lightweight projects with a simple, modern workflow by using extensions from the internal marketplace. +> **[Recaf](https://github.com/Col-E/Recaf)** β˜… 7.3k MIT 🟒
JVM reverse engineering toolkit, essentially an IDE for Java bytecode. -### Imagery +
-*Libraries that assist with the creation, evaluation or manipulation of graphical images.* +
+Caching 5 projects -- [Imgscalr](https://github.com/thebuzzmedia/imgscalr) - Simple, efficient and hardware-accelerated image-scaling library implemented in pure Java 2D. -- [Tess4J](https://github.com/nguyenq/tess4j) - A JNA wrapper for Tesseract OCR API. -- [Thumbnailator](https://github.com/coobird/thumbnailator) - High-quality thumbnail generation library. -- [TwelveMonkeys](https://github.com/haraldk/TwelveMonkeys) - Collection of plugins that extend the number of supported image file formats. -- [ZXing](https://github.com/zxing/zxing) - Multi-format 1D/2D barcode image processing library. - -### JSON - -*Libraries for serializing and deserializing JSON to and from Java objects.* - -- [DSL-JSON](https://github.com/ngs-doo/dsl-json) - JSON library with advanced compile time databinding. -- [Genson](https://owlike.github.io/genson) - Powerful and easy-to-use Java-to-JSON conversion library. -- [Gson](https://github.com/google/gson) - Serializes objects to JSON and vice versa. Good performance with on-the-fly usage. -- [HikariJSON](https://github.com/brettwooldridge/HikariJSON) - High-performance JSON parser, 2x faster than Jackson. -- [jackson-modules-java8](https://github.com/FasterXML/jackson-modules-java8) - Set of Jackson modules for Java 8 datatypes and features. -- [Jackson-datatype-money](https://github.com/zalando/jackson-datatype-money) - Open-source Jackson module to support JSON serialization and deserialization of JavaMoney data types. -- [Jackson](https://github.com/FasterXML/jackson) - Similar to GSON, but offers performance gains if you need to instantiate the library more often. -- [JSON-io](https://github.com/jdereg/json-io) - Convert Java to JSON. Convert JSON to Java. Pretty print JSON. Java JSON serializer. -- [jsoniter](http://jsoniter.com) - Fast and flexible library with iterator and lazy parsing API. -- [LoganSquare](https://github.com/bluelinelabs/LoganSquare) - JSON parsing and serializing library based on Jackson's streaming API. Outperforms GSON & Jackson's library. -- [Moshi](https://github.com/square/moshi) - Modern JSON library, less opinionated and uses built-in types like List and Map. -- [Yasson](https://github.com/eclipse/yasson) - Binding layer between classes and JSON documents similar to JAXB. - -### JSON Processing - -*Libraries for processing data in JSON format.* - -- [fastjson](https://github.com/alibaba/fastjson) - Very fast processor with no additional dependencies and full data binding. -- [Jolt](https://github.com/bazaarvoice/jolt) - JSON to JSON transformation tool. -- [JsonPath](https://github.com/jayway/JsonPath) - Extract data from JSON using XPATH-like syntax. -- [JsonSurfer](https://github.com/jsurfer/JsonSurfer) - Streaming JsonPath processor dedicated to processing big and complicated JSON data. - -### JVM and JDK - -*Current implementations of the JVM/JDK.* - -- [Avian](https://github.com/ReadyTalk/avian) - JVM with both JIT and AOT modes. Includes an iOS port. -- [Graal](https://github.com/oracle/graal) - Polyglot virtual machine which can be embedded. -- [OpenJ9](https://github.com/eclipse/openj9) - High performance, enterprise calibre, flexibly licensed, openly governed cross platform Java Virtual Machine extending and augmenting the runtime technology components from the Eclipse OMR and OpenJDK project. -- [OpenJDK](http://openjdk.java.net) - Open-source implementation for Linux. -- [ParparVM](https://github.com/codenameone/CodenameOne/tree/master/vm) - VM with non-blocking, concurrent GC for iOS. -- [Zulu OpenJDK 9](https://zulu.org/zulu-9-pre-release-downloads) - Early-access OpenJDK 9 builds for Windows, Linux, and Mac OS X. -- [Zulu OpenJDK](https://www.azul.com/downloads/zulu) - OpenJDK builds for Windows, Linux, and Mac OS X through Java 8. - -### Logging - -*Libraries that log the behavior of an application.* - -- [Apache Log4j 2](https://logging.apache.org/log4j) - Complete rewrite with a powerful plugin and configuration architecture. -- [Graylog](https://www.graylog.org) - Open-source aggregator suited for extended role and permission management. -- [Kibana](https://www.elastic.co/products/kibana) - Analyzes and visualizes log files. Some features require payment. -- [Logback](https://logback.qos.ch) - Robust logging library with interesting configuration options via Groovy. -- [Logbook](https://github.com/zalando/logbook) - Extensible, open-source library for HTTP request and response logging. -- [Logstash](https://www.elastic.co/products/logstash) - Tool for managing log files. -- [SLF4J](https://www.slf4j.org) - Abstraction layer/simple logging facade. -- [tinylog](http://www.tinylog.org) - Lightweight logging framework with static logger class. -- [Tracer](https://github.com/zalando/tracer) - Call tracing and log correlation in distributed systems. - -### Machine Learning - -*Tools that provide specific statistical algorithms for learning from data.* - -- [Apache Flink](https://flink.apache.org) - Fast, reliable, large-scale data processing engine. -- [Apache Mahout](https://mahout.apache.org) - Scalable algorithms focused on collaborative filtering, clustering and classification. -- [Apache Spark](https://spark.apache.org) - Data analytics cluster-computing framework. -- [DatumBox](http://www.datumbox.com) - Provides several algorithms and pre-trained models for natural language processing. -- [DeepDive](http://deepdive.stanford.edu) - Creates structured information from unstructured data and integrates it into an existing database. -- [Deeplearning4j](https://deeplearning4j.org) - Distributed and multi-threaded deep learning library. -- [H2O](https://www.h2o.ai) - Analytics engine for statistics over big data. -- [JSAT](https://github.com/EdwardRaff/JSAT) - Algorithms for pre-processing, classification, regression, and clustering with support for multi-threaded execution. -- [Oryx 2](https://github.com/OryxProject/oryx) - Framework for building real-time, large-scale machine learning applications. Includes end-to-end applications for collaborative filtering, classification, regression, and clustering. -- [Smile](https://haifengl.github.io/smile) - The Statistical Machine Intelligence and Learning Engine provides a set of machine learning algorithms and a visualization library. -- [Weka](https://www.cs.waikato.ac.nz/ml/weka) - Collection of algorithms for data mining tasks ranging from pre-processing to visualization. - -### Messaging - -*Tools that help send messages between clients to ensure protocol independency.* - -- [Aeron](https://github.com/real-logic/Aeron) - Efficient, reliable, unicast and multicast message transport. -- [Apache ActiveMQ](https://activemq.apache.org) - Message broker that implements JMS and converts synchronous to asynchronous communication. -- [Apache Camel](https://camel.apache.org) - Glues together different transport APIs via Enterprise Integration Patterns. -- [Apache Kafka](https://kafka.apache.org) - High-throughput distributed messaging system. -- [Apache Pulsar](https://pulsar.apache.org) - Distributed pub/sub-messaging system. -- [EventBus](https://github.com/greenrobot/EventBus) - Simple publish/subscribe event bus. -- [Hermes](http://hermes.allegro.tech) - Fast and reliable message broker built on top of Kafka. -- [JeroMQ](https://github.com/zeromq/jeromq) - Implementation of ZeroMQ. -- [Nakadi](https://github.com/zalando/nakadi) - Provides a RESTful API on top of Kafka. -- [RocketMQ](https://github.com/alibaba/RocketMQ) - A fast, reliable, and scalable distributed messaging platform. -- [Smack](https://github.com/igniterealtime/Smack) - Cross-platform XMPP client library. - -### Miscellaneous - -*Everything else.* - -- [Codename One](https://www.codenameone.com) - Cross-platform solution for writing native mobile apps. -- [CQEngine](https://github.com/npgall/cqengine) - Ultra-fast, SQL-like queries on Java collections. -- [Design Patterns](https://github.com/iluwatar/java-design-patterns) - Implementation and explanation of the most common design patterns. -- [Failsafe](https://github.com/jhalterman/failsafe) - Simple failure handling with retries and circuit breakers. -- [FF4J](http://www.ff4j.org) - Feature Flags for Java. -- [FizzBuzz Enterprise Edition](https://github.com/EnterpriseQualityCoding/FizzBuzzEnterpriseEdition) - No-nonsense implementation of FizzBuzz made by serious businessmen for serious business purposes. -- [J2ObjC](https://github.com/google/j2objc) - Java-to-Objective-C translator for porting Android libraries to iOS. -- [JavaX](http://javax.ai1.lol) - Reinventing and extending Java with a focus on simplicity. -- [JBake](http://jbake.org) - Static website generator. -- [JBot](https://github.com/ramswaroop/jbot) - Framework for building chatbots. -- [Jimfs](https://github.com/google/jimfs) - In-memory file system. -- [Joda-Money](http://www.joda.org/joda-money) - Basic currency and money classes and algorithms not provided by the JDK. -- [JPad](http://jpad.io) - Snippet runner. -- [Lanterna](https://github.com/mabe02/lanterna) - Easy console text-GUI library, similar to curses. -- [LightAdmin](http://lightadmin.org) - Pluggable CRUD UI library for rapid application development. -- [Maven Wrapper](https://github.com/takari/maven-wrapper) - Analogue of Gradle Wrapper for Maven, allows building projects without installing maven. -- [Membrane Service Proxy](https://github.com/membrane/service-proxy) - An open-source, reverse-proxy framework written in Java. -- [MinimalFTP](https://github.com/Guichaguri/MinimalFTP) - Lightweight, small and customizable FTP server. -- [Modern Java - A Guide to Java 8](https://github.com/winterbe/java8-tutorial) - Popular Java 8 guide. -- [Modernizer](https://github.com/andrewgaul/modernizer-maven-plugin) - Detect uses of legacy Java APIs. -- [Multi-OS Engine](https://software.intel.com/en-us/multi-os-engine) - An open-source, cross-platform engine to develop native mobile (iOS, Android, etc.) apps. -- [OpenRefine](http://openrefine.org) - Tool for working with messy data: cleaning, transforming, extending it with web services and linking it to databases. -- [Polyglot for Maven](https://github.com/takari/polyglot-maven) - Extensions for Maven 3.3.1+ that allows writing the POM model in dialects other than XML. -- [Smooks](https://github.com/smooks/smooks) - Extensible framework for building applications that process data which means bindings, transformations, message processing and enrichment. -- [Togglz](https://www.togglz.org) - Implementation of the Feature Toggles pattern. -- [TypeTools](https://github.com/jhalterman/typetools) - Tools for resolving generic types. -- [XMLBeam](https://github.com/SvenEwald/xmlbeam) - Processes XML by using annotations or XPath within code. -- [OctoLinker](https://github.com/OctoLinker/browser-extension) - Browser extension which allows to navigate through code on GitHub more efficiently. - -### Microservice - -*Tools for creating and managing microservices.* - -- [Apollo](https://spotify.github.io/apollo) - Libraries for writing composable microservices. -- [consul-api](https://github.com/Ecwid/consul-api) - Client for the [Consul](https://www.consul.io) API: a distributed, highly available and datacenter-aware registry/discovery service. -- [Eureka](https://github.com/Netflix/eureka) - REST-based service registry for resilient load balancing and failover. -- [Lagom](https://www.lightbend.com/lagom) - Framework for creating microservice-based systems. -- [Micronaut](http://micronaut.io) - Modern full-stack framework with focus on modularity, minimal memory footprint and startup time. - -### Monitoring - -*Tools that monitor applications in production.* - -- [AppDynamics ![c]](https://www.appdynamics.com) - Performance monitor. -- [Automon](https://github.com/stevensouza/automon) - Combines the power of AOP with monitoring and/or logging tools. -- [BugSnag ![c]](https://www.bugsnag.com) - Exception and error monitoring with an integration of several third party tools for a better workflow and a free hobbyist tier. -- [LeakCanary](https://github.com/square/leakcanary) - Memory leak detection. -- [Failsafe Actuator](https://github.com/zalando-incubator/failsafe-actuator) - Out of the box monitoring of Failsafe Circuit Breaker in Spring-Boot environment. -- [Glowroot](https://glowroot.org) - Open-source Java APM. -- [inspectIT](http://www.inspectit.rocks) - Captures detailed run-time information via hooks that can be changed on the fly. It supports tracing over multiple systems via the OpenTracing API and can correlate the data with end user monitoring. -- [Instrumental ![c]](https://instrumentalapp.com) - Real-time Java application performance monitoring. A commercial service with free development accounts. -- [JavaMelody](https://github.com/javamelody/javamelody) - Performance monitoring and profiling. -- [jmxtrans](https://github.com/jmxtrans/jmxtrans) - Connect to multiple JVMs and query them for their attributes via JMX. Its query language is based on JSON, which allows non-Java programmers to access the JVM attributes. Supports different output writes, including Graphite, Ganglia, and StatsD. -- [Jolokia](https://jolokia.org) - JMX over REST. -- [Kamon](http://www.kamon.io) - Tool for monitoring applications running on the JVM. -- [Metrics](http://metrics.dropwizard.io) - Expose metrics via JMX or HTTP and send them to a database. -- [New Relic ![c]](https://newrelic.com) - Performance monitor. -- [nudge4j](https://github.com/lorenzoongithub/nudge4j) - Remote developer console from the browser for Java 8 via bytecode injection. -- [OverOps ![c]](https://www.overops.com) - In-production error monitoring and debugging. -- [Pinpoint](https://github.com/naver/pinpoint) - Open-source APM tool. -- [Prometheus](https://prometheus.io) - Provides a multi-dimensional data model, DSL, autonomous server nodes and much more. -- [SPM ![c]](https://sematext.com/spm) - Performance monitor with distributing transaction tracing for JVM apps. -- [Stagemonitor](https://github.com/stagemonitor/stagemonitor) - Open-source performance monitoring and transaction tracing for JVM apps. -- [Sysmon](https://github.com/palantir/Sysmon) - Lightweight platform monitoring tool for Java VMs. -- [zipkin](https://zipkin.io) - Distributed tracing system which gathers timing data needed to troubleshoot latency problems in microservice architectures. - -### Native -*For working with platform-specific native libraries.* - -- [JavaCPP](https://github.com/bytedeco/javacpp) - Provides efficient and easy access to native C++. -- [JNA](https://github.com/java-native-access/jna) - Work with native libraries without writing JNI. Also provides interfaces to common system libraries. -- [JNR](https://github.com/jnr/jnr-ffi) - Work with native libraries without writing JNI. Also provides interfaces to common system libraries. Same goals as JNA, but faster, and serves as the basis for the upcoming [Project Panama](http://openjdk.java.net/projects/panama). - -### Natural Language Processing - -*Libraries that specialize in processing text.* - -- [CogCompNLP](https://github.com/CogComp/cogcomp-nlp) - Provides common annotators for plain text input. -- [CoreNLP](https://nlp.stanford.edu/software/corenlp.shtml) - Provides a set of fundamental tools for tasks like tagging, named entity recognition, and sentiment analysis. -- [DKPro](https://dkpro.github.io) - Collection of reusable NLP tools for linguistic pre-processing, machine learning, lexical resources, etc. -- [LingPipe](http://alias-i.com/lingpipe) - Toolkit for tasks ranging from POS tagging to sentiment analysis. - -### Networking - -*Libraries for building network servers.* - -- [Comsat](https://github.com/puniverse/comsat) - Integrates standard Java web-related APIs with Quasar fibers and actors. -- [Dubbo](https://github.com/alibaba/dubbo) - High-performance RPC framework. -- [Finagle](https://github.com/twitter/finagle) - Extensible RPC system for constructing high-concurrency servers. It implements uniform client and server APIs for several protocols, and is protocol-agnostic to simplify implementation of new protocols. -- [Grizzly](https://javaee.github.io/grizzly) - NIO framework. Used as a network layer in Glassfish. -- [gRPC](https://github.com/grpc/grpc-java) - RPC framework based on protobuf and HTTP/2. -- [KryoNet](https://github.com/EsotericSoftware/kryonet) - Provides a clean and simple API for efficient TCP and UDP client/server network communication using NIO and Kryo. -- [MINA](https://mina.apache.org) - Abstract, event-driven async I/O API for network operations over TCP/IP and UDP/IP via Java NIO. -- [Netty](https://netty.io) - Framework for building high-performance network applications. -- [Nifty](https://github.com/facebook/nifty) - Implementation of Thrift clients and servers on Netty. -- [sshj](https://github.com/hierynomus/sshj) - Programatically use SSH, SCP or SFTP. -- [Undertow](http://undertow.io) - Web server providing both blocking and non-blocking APIs based on NIO. Used as a network layer in WildFly. -- [urnlib](https://github.com/slub/urnlib) - Represent, parse and encode URNs, as in RFC 2141. - -### ORM - -*APIs that handle the persistence of objects.* - -- [Apache Cayenne](https://cayenne.apache.org) - Provides a clean, static API for data access. Also includes a GUI Modeler for working with database mappings, and DB reverse engineering and generation. -- [Ebean](https://ebean-orm.github.io) - Provides simple and fast data access. -- [EclipseLink](https://www.eclipse.org/eclipselink) - Supports a number of persistence standards: JPA, JAXB, JCA and SDO. -- [Hibernate](http://hibernate.org/orm) - Robust and widely used, with an active community. -- [MyBatis](http://www.mybatis.org/mybatis-3) - Couples objects with stored procedures or SQL statements. -- [SimpleFlatMapper](https://github.com/arnaudroger/SimpleFlatMapper) - Simple database and CSV mapper. - -### PaaS - -*Java platform as a service.* - -- [AWS Elastic Beanstalk ![c]](https://aws.amazon.com/elasticbeanstalk) - AWS-based, with support for Tomcat and Jetty. -- [AWS Lambda ![c]](https://aws.amazon.com/lambda) - Serverless computation. -- [Google App Engine ![c]](https://cloud.google.com) - PaaS on Google's infrastructure. -- [Heroku ![c]](https://www.heroku.com) - Abstract computing environments. -- [Jelastic ![c]](https://jelastic.com) - Supports Tomcat, Jetty, GlassFish, JBoss, TomEE and WildFly. -- [OpenShift Enterprise ![c]](https://www.openshift.com) - On-premise solution. - -### PDF - -*Tools to help with PDF file creation.* - -- [Apache FOP](https://xmlgraphics.apache.org/fop) - Creates PDFs from XSL-FO. -- [Apache PDFBox](https://pdfbox.apache.org) - Toolbox for creating and manipulating PDFs. -- [Dynamic Jasper](http://dynamicjasper.com) - Abstraction layer to JasperReports. -- [DynamicReports](http://dynamicreports.org) - Simplifies JasperReports. -- [flyingsaucer](https://github.com/flyingsaucerproject/flyingsaucer) - XML/XHTML and CSS 2.1 renderer. -- [iText ![c]](https://itextpdf.com) - Creates PDF files programmatically. -- [JasperReports](https://community.jaspersoft.com/project/jasperreports-library) - Complex reporting engine. - -### Performance analysis - -*Tools for performance analysis, profiling and benchmarking.* - -- [fastThread ![c]](http://fastthread.io) - Analyze and visualize thread dumps with a free cloud-based upload interface. -- [GCeasy ![c]](http://gceasy.io) - Tool to analyze and visualize GC logs. It provides a free cloud-based upload interface. -- [honest-profiler](https://github.com/RichardWarburton/honest-profiler) - A low-overhead, bias-free sampling profiler. -- [jHiccup](https://github.com/giltene/jHiccup) - Logs and records platform JVM stalls. -- [JITWatch](https://github.com/AdoptOpenJDK/jitwatch) - Analyze the JIT compiler optimisations made by the HotSpot JVM. -- [JMH](http://openjdk.java.net/projects/code-tools/jmh) - a Java harness for building, running, and analysing nano/micro/milli/macro benchmarks written in Java and other languages targeting the JVM. -- [JProfiler ![c]](https://www.ej-technologies.com/products/jprofiler/overview.html) - Database profiling for JDBC, JPA and NoSQL, with JEE support. -- [LatencyUtils](https://github.com/LatencyUtils/LatencyUtils) - Utilities for latency measurement and reporting. -- [XRebel ![c]](https://zeroturnaround.com/software/xrebel) - Real-time profiling for web applications, with an in-browser widget. -- [YourKit Java Profiler ![c]](https://www.yourkit.com/features) - Profiler for any application running on the JVM. - -### Platform - -*Frameworks that are suites of multiple libraries encompassing several categories.* - -#### Apache Commons - -- [Pool](http://commons.apache.org/proper/commons-pool) - Generic object pooling component. -- [BCEL](http://commons.apache.org/proper/commons-bcel) - Byte Code Engineering Library - analyze, create, and manipulate Java class files. -- [Codec](http://commons.apache.org/proper/commons-codec) - General encoding/decoding algorithms (for example phonetic, base64, URL). -- [Compress](http://commons.apache.org/proper/commons-compress) - Defines an API for working with tar, zip and bzip2 files. -- [IO](http://commons.apache.org/proper/commons-io) - Collection of I/O utilities. -- [Configuration](http://commons.apache.org/proper/commons-configuration) - Reading of configuration/preferences files in various formats. -- [VFS](http://commons.apache.org/proper/commons-vfs) - Virtual File System component for treating files, FTP, SMB, ZIP and such like as a single logical file system. -- [Jelly](http://commons.apache.org/proper/commons-jelly) - XML based scripting and processing engine. -- [CSV](http://commons.apache.org/proper/commons-csv) - Component for reading and writing comma separated value files. -- [JCS](http://commons.apache.org/proper/commons-jcs) - Java Caching System. -- [Email](http://commons.apache.org/proper/commons-email) - Library for sending e-mail from Java. -- [DbUtils](http://commons.apache.org/proper/commons-dbutils) - JDBC helper library. -- [FileUpload](http://commons.apache.org/proper/commons-fileupload) - File upload capability for your servlets and web applications. -- [Lang](http://commons.apache.org/proper/commons-lang) - Provides extra functionality for classes in java.lang. -- [Jexl](http://commons.apache.org/proper/commons-jexl) - Expression language which extends the Expression Language of the JSTL. -- [CLI](http://commons.apache.org/proper/commons-cli) - Command Line arguments parser. -- [Validator](http://commons.apache.org/proper/commons-validator) - Framework to define validators and validation rules in an xml file. -- [Net](http://commons.apache.org/proper/commons-net) - Collection of network utilities and protocol implementations. -- [RNG](https://commons.apache.org/proper/commons-rng) - Commons Rng provides implementations of pseudo-random numbers generators. -- [RDF](https://commons.apache.org/proper/commons-rdf) - Common implementation of RDF 1.1 that could be implemented by systems on the JVM. -- [Weaver](http://commons.apache.org/proper/commons-weaver) - Provides an easy way to enhance (weave) compiled bytecode. -- [BeanUtils](http://commons.apache.org/proper/commons-beanutils) - Easy-to-use wrappers around the Java reflection and introspection APIs. -- [Collections](http://commons.apache.org/proper/commons-collections) - Extends or augments the Java Collections Framework. -- [DBCP](http://commons.apache.org/proper/commons-dbcp) - Database connection pooling services. -- [Math](http://commons.apache.org/proper/commons-math) - Lightweight, self-contained mathematics and statistics components. -- [Exec](http://commons.apache.org/proper/commons-exec) - API for dealing with external process execution and environment management in Java. -- [Logging](https://en.wikipedia.org/wiki/Apache_Commons_Logging) Wrapper around a variety of logging API implementations. -- [OGNL](http://commons.apache.org/proper/commons-ognl) - An Object-Graph Navigation Language. -- [JCI](http://commons.apache.org/proper/commons-jci) - Java Compiler Interface. -- [Daemon](http://commons.apache.org/proper/commons-daemon) - Alternative invocation mechanism for unix-daemon-like java code. -- [Functor](http://commons.apache.org/proper/commons-functor) - A functor is a function that can be manipulated as an object, or an object representing a single, generic function. -- [Digester](http://commons.apache.org/proper/commons-digester) - XML-to-Java-object mapping utility. -- [BSF](http://commons.apache.org/proper/commons-bsf) - Bean Scripting Framework - interface to scripting languages, including JSR-223. -- [Imaging](http://commons.apache.org/proper/commons-imaging) - A pure-Java image library. -- [SCXML](http://commons.apache.org/proper/commons-scxml) - An implementation of the State Chart XML specification aimed at creating and maintaining a Java SCXML engine. -- [JXPath](http://commons.apache.org/proper/commons-jxpath) - Utilities for manipulating Java Beans using the XPath syntax. -- [Chain](http://commons.apache.org/proper/commons-chain) - Chain of Responsibility pattern implementation. -- [Proxy](http://commons.apache.org/proper/commons-proxy) - Library for creating dynamic proxies. -- [BeanUtils2](http://commons.apache.org/sandbox/commons-beanutils2) - Redesign of Commons BeanUtils. -- [ClassScan](http://commons.apache.org/sandbox/commons-classscan) - Find Class interfaces, methods, fields, and annotations without loading. -- [CLI2](http://commons.apache.org/sandbox/commons-cli2) Redesign of Commons CLI. -- [Convert](http://commons.apache.org/sandbox/commons-convert) - Commons-Convert aims to provide a single library dedicated to the task of converting an object of one type to another. -- [Finder](http://commons.apache.org/sandbox/commons-finder) - Java library inspired by the UNIX find command. -- [Flatfile](http://commons.apache.org/sandbox/commons-flatfile) - Java library for working with flat data structures. -- [Graph](http://commons.apache.org/sandbox/commons-graph) - A general purpose Graph APIs and algorithms. -- [I18n](http://commons.apache.org/sandbox/commons-i18n) - Adds the feature of localized message bundles that consist of one or many localized texts that belong together. -- [Id](http://commons.apache.org/sandbox/commons-id) - Id is a component used to generate identifiers. -- [Javaflow](http://commons.apache.org/sandbox/commons-javaflow) - Continuation implementation to capture the state of the application. -- [JNet](http://commons.apache.org/sandbox/commons-jnet) - JNet allows to use dynamically register url stream handlers through the java.net API. -- [Monitoring](http://commons.apache.org/sandbox/commons-monitoring) - Monitoring aims to provide a simple but extensible monitoring solution for Java applications. -- [Nabla](http://commons.apache.org/sandbox/commons-nabla) - Nabla provides automatic differentiation classes that can generate derivative of any function implemented in the Java language. -- [OpenPGP](http://commons.apache.org/sandbox/commons-openpgp) - Interface to signing and verifying data using OpenPGP. -- [Performance](http://commons.apache.org/sandbox/commons-performance) - A small framework for microbenchmark clients, with implementations for Commons DBCP and Pool. -- [Pipeline](http://commons.apache.org/sandbox/commons-pipeline) - Provides a set of pipeline utilities designed around work queues that run in parallel to sequentially process data objects. - -#### Other - -- [CUBA Platform](https://cuba-platform.com) - High-level framework for developing enterprise applications with a rich web interface, based on Spring, EclipseLink and Vaadin. -- [Light-Java](https://github.com/networknt/light-java) - A fast, lightweight and productive microservices framework with built-in [security](https://github.com/networknt/light-oauth2). -- [Orienteer](https://github.com/OrienteerBAP/Orienteer) - Open-source business application platform for rapid configuration/development of CRM, ERP, LMS and other applications. -- [Spring](https://spring.io/projects) - Provides many packages for dependency injection, aspect-oriented programming, security, etc. - -### Reactive libraries - -*Libraries for developing reactive applications.* - -- [Akka](https://akka.io) - Toolkit and runtime for building concurrent, distributed, fault-tolerant and event-driven applications. -- [Reactive Streams](https://github.com/reactive-streams/reactive-streams-jvm) - Provides a standard for asynchronous stream processing with non-blocking backpressure. -- [Reactor](https://projectreactor.io) - Library for building reactive fast-data applications. -- [RxJava](https://github.com/ReactiveX/RxJava) - Allows for composing asynchronous and event-based programs using observable sequences. -- [vert.x](http://vertx.io) - Polyglot event-driven application framework. - -### REST Frameworks - -*Frameworks specifically for creating RESTful services.* - -- [Dropwizard](https://dropwizard.github.io/dropwizard) - Opinionated framework for setting up modern web applications with Jetty, Jackson, Jersey and Metrics. -- [Jersey](https://jersey.github.io) - JAX-RS reference implementation. -- [Microserver](https://github.com/aol/micro-server) β€” A convenient, extensible microservices plugin system for Spring & Spring Boot. With more than 30 plugins and growing, it supports both micro-monolith and pure microservices styles. -- [Rapidoid](https://www.rapidoid.org) - A simple, secure and extremely fast framework consisting of an embedded HTTP server, GUI components and dependency injection. -- [rest.li](https://github.com/linkedin/rest.li) - Framework for building robust, scalable RESTful architectures using typesafe bindings and asynchronous, non-blocking IO with an end-to-end developer workflow that promotes clean practices, uniform interface design and consistent data modeling. -- [RESTEasy](https://resteasy.jboss.org) - Fully certified and portable implementation of the JAX-RS specification. -- [RestExpress](https://github.com/RestExpress/RestExpress) - Thin wrapper on the JBoss Netty HTTP stack that provides scaling and performance. -- [Restlet Framework](https://github.com/restlet/restlet-framework-java) - Pioneering framework with powerful routing and filtering capabilities, and a unified client and server API. -- [Spark](http://sparkjava.com) - Sinatra inspired framework. -- [Crnk](http://www.crnk.io) - Implementation of the JSON API specification to build resource-oriented REST endpoints with sorting, filtering, paging, linking, object graphs, type-safety, bulk updates, integrations and more. -- [Swagger](https://swagger.io) - Standard, language-agnostic interface to REST APIs. - -### Science - -*Libraries for scientific computing, analysis and visualization.* - -- [DataMelt](http://jwork.org/dmelt) - Environment for scientific computation, data analysis and data visualization. -- [Erdos](https://github.com/Erdos-Graph-Framework/Erdos) - Modular, light and easy graph framework for theoretic algorithms. -- [GraphStream](http://graphstream-project.org) - Library for modeling and analyzing dynamic graphs. -- [JGraphT](https://github.com/jgrapht/jgrapht) - Graph library that provides mathematical graph-theory objects and algorithms. -- [JGraphX](https://github.com/jgraph/jgraphx) - Library for visualizing (mainly Swing) and interacting with node-edge graphs. -- [Mines Java Toolkit](https://github.com/MinesJTK/jtk) - Library for geophysical scientific computation, visualization and digital signal analysis. -- [Morpheus](http://www.zavtech.com/morpheus/docs) - Provides a versatile two-dimensional memory efficient tabular data structure called a DataFrame to enable efficient in-memory analytics for scientific computing on the JVM. -- [Tablesaw](https://github.com/lwhite1/tablesaw) - Includes a data-frame, an embedded column store, and hundreds of methods to transform, summarize, or filter data. - -### Search - -*Engines that index documents for search and analysis.* - -- [Apache Lucene](https://lucene.apache.org) - High-performance, full-featured, cross-platform, text search engine library. -- [Apache Solr](https://lucene.apache.org/solr) - Enterprise search engine optimized for high-volume traffic. -- [Elasticsearch](https://www.elastic.co) - Distributed, multitenant-capable, full-text search engine with a RESTful web interface and schema-free JSON documents. - -### Security - -*Libraries that handle security, authentication, authorization or session management.* - -- [Apache Shiro](https://shiro.apache.org) - Performs authentication, authorization, cryptography and session management. -- [Bouncy Castle](https://www.bouncycastle.org/java.html) - All-purpose cryptographic library and JCA provider offering a wide range of functions, from basic helpers to PGP/SMIME operations. -- [Cryptomator](https://cryptomator.org) - Multiplatform, transparent, client-side encryption of files in the cloud. -- [Hdiv](https://github.com/hdiv/hdiv) - Runtime application that repels application security risks included in the OWASP Top 10, including SQL injection, cross-site scripting, cross-site request forgery, data tampering, and brute force attacks. -- [jjwt](https://github.com/jwtk/jjwt) - JSON web token for Java and Android. -- [Keycloak](https://keycloak.jboss.org) - Integrated SSO and IDM for browser apps and RESTful web services. -- [Keyczar](https://github.com/google/keyczar) - Easy-to-use, safe encryption framework with key versioning. -- [Keywhiz](https://github.com/square/keywhiz) - System for distributing and managing secrets. -- [Nbvcxz](https://github.com/GoSimpleLLC/nbvcxz) - Advanced password strength estimation. -- [OACC](http://oaccframework.org) - Provides permission-based authorization services. -- [pac4j](https://github.com/pac4j/pac4j) - Security engine. -- [PicketLink](http://picketlink.org) - Umbrella project for security and identity management. -- [Vault](https://www.vaultproject.io) - Secures, stores, and tightly controls access to tokens, passwords, certificates, API keys, and other secrets. It handles leasing, key revocation, key rolling, and auditing. Through a unified API, users can access an encrypted Key/Value store and network encryption-as-a-service, or generate AWS IAM/STS credentials, SQL/NoSQL databases, X.509 certificates, SSH credentials, and more. - -### Serialization - -*Libraries that handle serialization with high efficiency.* - -- [FlatBuffers](https://github.com/google/flatbuffers) - Memory-efficient serialization library that can access serialized data without unpacking and parsing it. -- [FST](https://github.com/RuedigerMoeller/fast-serialization) - JDK-compatible, high-performance object graph serialization. -- [Kryo](https://github.com/EsotericSoftware/kryo) - Fast and efficient object graph serialization framework. -- [MessagePack](https://github.com/msgpack/msgpack-java) - Efficient binary serialization format. -- [PHP Serializer](https://github.com/marcospassos/java-php-serializer) - Serializing objects in the PHP serialization format. +_Libraries that provide caching facilities._ -### Server +> **[cache2k](https://github.com/cache2k/cache2k)** β˜… 742 Apache-2.0 πŸ”΄
In-memory high performance caching library. -*Servers specifically used to deploy applications.* +> **[Caffeine](https://github.com/ben-manes/caffeine)** β˜… 17.8k Apache-2.0 🟒
High-performance, near-optimal caching library. -- [Apache Tomcat](https://tomcat.apache.org) - Robust, all-round server for Servlet and JSP. -- [Apache TomEE](https://tomee.apache.org) - Tomcat plus Java EE. -- [Jetty](https://www.eclipse.org/jetty) - Provides a Web server and javax.servlet container, plus support for HTTP/2, WebSocket, OSGi, JMX, JNDI, JAAS and many other integrations. -- [nanohttpd](https://github.com/NanoHttpd/nanohttpd) - Tiny, easily embeddable HTTP server. -- [WebSphere Liberty](https://developer.ibm.com/wasdev) - Lightweight, modular server developed by IBM. -- [WildFly](http://www.wildfly.org) - Formerly known as JBoss and developed by Red Hat with extensive Java EE support. +> **[Ehcache](https://github.com/ehcache/ehcache3)** β˜… 2.1k Apache-2.0 🟒
Distributed general-purpose cache. -### Template Engine +> **[Infinispan](https://github.com/infinispan/infinispan)** β˜… 1.3k Apache-2.0 🟒
Highly concurrent key/value datastore used for caching. -*Tools that substitute expressions in a template.* +> **[JetCache](https://github.com/alibaba/jetcache)** β˜… 5.6k Apache-2.0 🟒
Java cache framework with local and distributed caching, annotations and asynchronous APIs. -- [Handlebars.java](https://jknack.github.io/handlebars.java) - Logicless and semantic Mustache templates. -- [Jade4J](https://github.com/neuland/jade4j) - Implementation of Pug (formerly known as Jade). -- [Jtwig](http://jtwig.org) - Modular, configurable and fully tested template engine. -- [Pebble](http://www.mitchellbosecke.com/pebble/home) - Inspired by Twig and separates itself with its inheritance feature and its easy-to-read syntax. It ships with built-in autoescaping for security and it includes integrated support for internationalization. -- [Thymeleaf](http://www.thymeleaf.org) - Aims to be a substitute for JSP and works for XML files. +
-### Testing +
+CLI 9 projects -*Tools that test from model to the view.* +_Libraries for everything related to the CLI._ -#### Asynchronous +#### Argument Parsing 5 projects -*Tools that simplify testing asynchronous services.* +_Libraries to assist with parsing command line arguments._ -- [Awaitility](https://github.com/jayway/awaitility) - DSL for synchronizing asynchronous operations. -- [ConcurrentUnit](https://github.com/jhalterman/concurrentunit) - Toolkit for testing multi-threaded and asynchronous applications. -- [GreenMail](http://www.icegreen.com/greenmail) - In-memory email server for integration testing. Supports SMTP, POP3 and IMAP including SSL. -- [Hoverfly Java](https://github.com/SpectoLabs/hoverfly-java) - Native bindings for Hoverfly, a proxy which allows you to simulate HTTP services. -- [REST Assured](https://github.com/jayway/rest-assured) - DSL for easy testing of REST/HTTP services. +> **[Airline](https://github.com/rvesse/airline)** β˜… 145 Apache-2.0 🟒
Annotation-based framework for parsing Git-like command-line arguments. -#### BDD +> **[jbock](https://github.com/jbock-java/jbock)** β˜… 94 MIT 🟒
Reflectionless command line parser. -*Testing for the software development process that emerged from TDD and was heavily influenced by DDD and OOAD.* +> **[JCommander](https://github.com/cbeust/jcommander)** β˜… 2.0k Apache-2.0 🟠
Command-line argument-parsing framework with custom types and validation via implementing interfaces. -- [Cucumber](https://github.com/cucumber/cucumber-jvm) - Provides a way to describe features in a plain language which customers can understand. -- [Cukes-REST](https://github.com/ctco/cukes-rest) - A collection of Gherkin steps for REST-service testing using Cucumber. -- [J8Spec](https://github.com/j8spec/j8spec) - Follows a Jasmine-like syntax. -- [JBehave](http://jbehave.org) - Extensively configurable framework that describes stories. -- [JGiven](http://jgiven.org) - Provides a fluent API which allows for simpler composition. -- [Lamdba Behave](https://github.com/RichardWarburton/lambda-behave) - Aims to provide a fluent API to write tests in long and descriptive sentences that read like plain English. +> **[JLine](https://github.com/jline/jline3)** β˜… 1.8k 🟒
Includes features from modern shells like completion or history. -#### Fixtures +> **[picocli](https://github.com/remkop/picocli)** β˜… 5.4k Apache-2.0 🟒
ANSI colors and styles in usage help with annotation-based POSIX/GNU/any syntax, subcommands, strong typing for both options and positional args. -*Everything related to the creation and handling of random data.* +#### Text-Based User Interfaces 4 projects -- [Beanmother](https://github.com/keepcosmos/beanmother) - Sets up beans from YAML fixtures. -- [Fixture Factory](https://github.com/six2six/fixture-factory) - Generates fake objects from a template. -- [JFairy](https://github.com/Codearte/jfairy) - Fake data generator. -- [Randomized Testing](https://github.com/randomizedtesting/randomizedtesting) - JUnit test runner and plugins for running JUnit tests with pseudo-randomness. +_Libraries that provide TUI frameworks, or building blocks related functions._ -#### Frameworks +> **[AliveJTUI](https://github.com/yehorsyrin/alivejTUI)** β˜… 9 🟠
Declarative, React-style TUI library for building terminal UIs as component trees with diff-based rendering, focus management, and themes. -*Provide environments to run tests for a specific use case.* +> **[Jansi](https://github.com/fusesource/jansi)** β˜… 1.2k Apache-2.0 🟠
ANSI escape codes to format console output. -- [ArchUnit](https://github.com/TNG/ArchUnit) - Test library for specifying and asserting architecture rules. -- [Apache JMeter](http://jmeter.apache.org) - Functional testing and performance measurements. -- [Arquillian](http://arquillian.org) - Integration and functional testing platform for Java EE containers. -- [Citrus](https://citrusframework.org) - Integration testing framework that focuses on both client- and server-side messaging. -- [Gatling](https://gatling.io) - Load testing tool designed for ease of use, maintainability and high performance. -- [JUnit](http://junit.org) - Common testing framework. -- [Pact JVM](https://github.com/DiUS/pact-jvm) - Consumer-driven contract testing. -- [PIT](http://pitest.org) - Fast mutation-testing framework for evaluating fault-detection abilities of existing JUnit or TestNG test suites. +> **[Jexer](https://gitlab.com/AutumnMeowMeow/jexer)**
Advanced console (and Swing) text user interface (TUI) library, with mouse-draggable windows, built-in terminal window manager, and sixel image support. Looks like [Turbo Vision](https://en.wikipedia.org/wiki/Turbo_Vision). -#### Matchers +> **[Lanterna](https://github.com/mabe02/lanterna)** β˜… 2.6k LGPL-3.0 🟒
Easy console text-GUI library, similar to curses. -*Libraries that provide custom matchers.* +
-- [AssertJ](https://joel-costigliola.github.io/assertj) - Fluent assertions that improve readability. -- [JSONAssert](http://jsonassert.skyscreamer.org) - Simplifies testing JSON strings. -- [Truth](https://github.com/google/truth) - Google's assertion and proposition framework. +
+Cloud 6 projects -#### Miscellaneous +_Libraries to integrate or use cloud-specific features._ -*Other stuff related to testing.* +> **[AWS SDK for Java 2.x](https://github.com/aws/aws-sdk-java-v2)** β˜… 2.6k Apache-2.0 🟒
Official Java APIs for interacting with Amazon Web Services. -- [Mutability Detector](https://github.com/MutabilityDetector/MutabilityDetector) - Reports whether instances of a given class are immutable. -- [raml-tester](https://github.com/nidi3/raml-tester) - Tests if a request/response matches a given RAML definition. -- [TestContainers](https://github.com/testcontainers/testcontainers-java) - Provides throwaway instances of common databases, Selenium web browsers, or anything else that can run in a Docker container. -- [pojo-tester](http://www.pojo.pl) - Automatically performs tests on basic POJO methods. +> **[Google Cloud Client Libraries](https://github.com/googleapis/google-cloud-java)** β˜… 2.1k Apache-2.0 🟒
Client libraries for accessing Google Cloud services from Java applications. -#### Mocking +> **[Java Operator SDK](https://github.com/operator-framework/java-operator-sdk)** β˜… 936 Apache-2.0 🟒
SDK for implementing Kubernetes operators in Java. -*Tools which mock collaborators to help testing single, isolated units.* +> **[Kubernetes Java Client](https://github.com/kubernetes-client/java)** β˜… 4.0k Apache-2.0 🟒
Official Java client for the Kubernetes API. -- [JMockit](http://jmockit.org) - Integration testing, API mocking and faking, and code coverage. -- [Mockito](https://github.com/mockito/mockito) - Mocking framework that lets you write tests with a clean and simple API. -- [MockServer](https://www.mock-server.com) - Allows mocking of systems integrated with HTTPS. -- [Moco](https://github.com/dreamhead/moco) - Concise web services for stubs and mocks. -- [PowerMock](https://github.com/jayway/powermock) - Mocks static methods, constructors, final classes and methods, private methods, and removal of static initializers. -- [WireMock](http://wiremock.org) - Stubs and mocks web services. +> **[kubernetes-client](https://github.com/fabric8io/kubernetes-client)** β˜… 3.7k Apache-2.0 🟒
Client provides access to the full Kubernetes & OpenShift REST APIs via a fluent DSL. -#### Parameterization +> **[minio-java](https://github.com/minio/minio-java)** β˜… 1.3k Apache-2.0 🟒
Provides simple APIs to access any Amazon S3-compatible object storage server. -*Simplifies the writing of parameterized tests.* +
-- [Burst](https://github.com/square/burst) - A unit testing library for varying test data. -- [junit-dataprovider](https://github.com/TNG/junit-dataprovider) - A TestNG-like data provider/runner for JUnit. -- [JUnitParams](https://pragmatists.github.io/JUnitParams) - Creates readable and maintainable parametrised tests. +
+Code Analysis 16 projects -### Utility +_Tools that provide metrics and quality measurements._ -*Libraries which provide general utility functions.* +> **[Checkstyle](https://github.com/checkstyle/checkstyle)** β˜… 9.0k LGPL-2.1 🟒
Static analysis of coding conventions and standards. -- [cactoos](http://www.cactoos.org) - Collection of object-oriented primitives. -- [CRaSH](http://www.crashub.org) - Provides a shell into a JVM that's running CRaSH. Used by Spring Boot and others. -- [Dex](https://github.com/PatMartin/Dex) - Java/JavaFX tool capable of powerful ETL and data visualization. -- [Embulk](http://www.embulk.org) - Bulk data loader that helps data transfer between various databases, storages, file formats, and cloud services. -- [fswatch](https://github.com/vorburger/ch.vorburger.fswatch) - Micro library to watch for directory file system changes, simplifying java.nio.file.WatchService -- [Gephi](https://github.com/gephi/gephi) - Cross-platform for visualizing and manipulating large graph networks. -- [Guava](https://github.com/google/guava) - Collections, caching, primitives support, concurrency libraries, common annotations, string processing, I/O, and more. -- [JADE](http://jade.tilab.com) - Framework and environment for building and debugging multi-agent systems. -- [JavaVerbalExpressions](https://github.com/VerbalExpressions/JavaVerbalExpressions) - Library that helps with constructing difficult regular expressions. -- [JGit](https://eclipse.org/jgit) - A lightweight, pure Java library implementing the Git version control system. -- [minio-java](https://github.com/minio/minio-java) - Provides simple APIs to access any Amazon S3-compatible object storage server. -- [ProtΓ©gΓ©](https://protege.stanford.edu) - Provides an ontology editor and a framework to build knowledge-based systems. -- [Underscore-java](https://github.com/javadev/underscore-java) - Port of Underscore.js functions. +> **[Error Prone](https://github.com/google/error-prone)** β˜… 7.2k Apache-2.0 🟒
Catches common programming mistakes as compile-time errors. -### Version Managers +> **[Error Prone Support](https://github.com/PicnicSupermarket/error-prone-support)** β˜… 37 MIT 🟒
Error Prone extensions: extra bug checkers and a large battery of Refaster templates. -*Utilities that help create the development shell environment and switch between different Java versions.* +> **[Infer](https://github.com/facebook/infer)** β˜… 15.7k MIT 🟒
Modern static analysis tool for verifying the correctness of code. -- [jabba](https://github.com/shyiko/jabba) - Java Version Manager inspired by nvm. Supports Mac OS X, Linux and Windows. -- [jenv](https://github.com/gcuisinier/jenv) - Java Version Manager inspired by rbenv. Can configure globally or per project. Tested on Debian and Mac OS X. -- [SDKMan](https://github.com/sdkman/sdkman-cli) - Java Version Manager inspired by RVM and rbenv. Supports UNIX-based platforms and Windows. +> **[JSpecify](https://github.com/jspecify/jspecify)** β˜… 1.1k Apache-2.0 🟒
Standardized nullness annotations designed to work uniformly across various Java IDEs, compilers, and static analysis tools. -### Web Crawling +> **[Modernizer](https://github.com/gaul/modernizer-maven-plugin)** β˜… 391 Apache-2.0 🟒
Detect uses of legacy Java APIs. -*Libraries that analyze the content of websites.* +> **[Mutability Detector](https://github.com/MutabilityDetector/MutabilityDetector)** β˜… 246 Apache-2.0 🟠
Reports whether instances of a given class are immutable. -- [Apache Nutch](https://nutch.apache.org) - Highly extensible, highly scalable web crawler for production environments. -- [Crawler4j](https://github.com/yasserg/crawler4j) - Simple and lightweight web crawler. -- [jsoup](https://jsoup.org) - Scrapes, parses, manipulates and cleans HTML. -- [StormCrawler](http://stormcrawler.net) - SDK for building low-latency and scalable web crawlers. -- [webmagic](https://github.com/code4craft/webmagic) - Scalable crawler with downloading, url management, content extraction and persistent. +> **[NullAway](https://github.com/uber/NullAway)** β˜… 4.1k MIT 🟒
Eliminates NullPointerExceptions with low build-time overhead. -### Web Frameworks +> **[OpenRewrite](https://github.com/openrewrite/rewrite)** β˜… 3.6k Apache-2.0 🟒
Automates large-scale source-code refactoring through reusable recipes. -*Frameworks that handle the communication between the layers of a web application.* +> **[OpenTaint](https://github.com/seqra/opentaint)** β˜… 126 Apache-2.0 🟒
Interprocedural taint analyzer for Java and Spring applications with reusable security rules and dependency models. -- [Apache Tapestry](https://tapestry.apache.org) - Component-oriented framework for creating dynamic, robust, highly scalable web applications. -- [Apache Wicket](https://wicket.apache.org) - Component-based web application framework similar to Tapestry, with a stateful GUI. -- [Blade](https://github.com/biezhi/blade) - Lightweight, modular framework that aims to be elegant and simple. -- [Bootique](http://bootique.io) - Minimally opinionated framework for runnable apps. -- [Firefly](http://www.fireflysource.com) - Asynchronous framework for rapid development of high-performance web application. -- [Grails](https://grails.org) - Groovy framework that provides a highly productive environment by favoring convention over configuration, no XML and support for mixins. -- [Jooby](http://jooby.org) - Scalable, fast and modular micro-framework that offers multiple programming models. -- [Ninja](http://www.ninjaframework.org) - Full-stack web framework. -- [Pippo](http://www.pippo.ro) - Small, highly modularized, Sinatra-like framework. -- [Play](https://www.playframework.com) - Built on Akka, it provides predictable and minimal resource consumption (CPU, memory, threads) for highly-scalable applications in Java and Scala. -- [PrimeFaces](https://primefaces.org) - JSF framework with both free and commercial/support versions and frontend components. -- [Ratpack](https://ratpack.io) - Set of libraries that facilitate fast, efficient, evolvable and well-tested HTTP applications. -- [Takes](https://github.com/yegor256/takes) - Opinionated web framework which is built around the concepts of True Object-Oriented Programming and immutability. -- [Vaadin](https://vaadin.com/home) - Event-driven framework built on top of GWT. Uses server-side architecture with Ajax on the client side. +> **[PMD](https://github.com/pmd/pmd)** β˜… 5.5k 🟒
Source code analysis for finding bad coding practices. -## Resources +> **[RefactorFirst](https://github.com/jimbethancourt/RefactorFirst)** β˜… 542 Apache-2.0 🟒
Identifies and prioritizes God Classes and Highly Coupled classes. + +> **[SonarJava](https://github.com/SonarSource/sonar-java)** β˜… 1.2k 🟒
Static analyzer for SonarQube & SonarLint. (LGPL-3.0-only) + +> **[Spoon](https://github.com/INRIA/spoon)** β˜… 1.9k 🟒
Library for analyzing and transforming Java source code. + +> **[Spotbugs](https://github.com/spotbugs/spotbugs)** β˜… 3.9k LGPL-2.1 🟒
Static analysis of bytecode to find potential bugs. + +> **[ToolsHref](https://github.com/toolshref-tools/toolshref-tools)** β˜… 0 🟠
Online Java code analyzer and JSON-to-Mermaid visualization tool. + +
+ +
+Code Coverage 3 projects + +_Frameworks and tools that enable code coverage metrics collection for test suites._ + +> **[Delta Coverage](https://github.com/gw-kit/delta-coverage-plugin)** β˜… 40 MIT 🟒
Computes code coverage of new and modified code based on a provided diff, supporting JaCoCo and IntelliJ coverage engines. + +> **[JaCoCo](https://github.com/jacoco/jacoco)** β˜… 4.6k 🟒
Framework that enables collection of code coverage metrics, using both offline and runtime bytecode instrumentation. + +> **[OpenClover](https://github.com/openclover/clover)** β˜… 70 🟒
Measures Java code coverage through source-code instrumentation, with build-tool and IDE integrations. + +
+ +
+Code Formatting 4 projects + +_Tools that format or restructure Java source code._ + +> **[google-java-format](https://github.com/google/google-java-format)** β˜… 6.2k 🟒
Reformats Java source code to follow Google Java Style. + +> **[JHarmonizer](https://github.com/lemon-ant/JHarmonizer)** β˜… 26 🟒
Safely reorders Java source code with configurable rules and Palantir Java Format. + +> **[Palantir Java Format](https://github.com/palantir/palantir-java-format)** β˜… 856 Apache-2.0 🟒
Formatter based on google-java-format with wider lines and lambda-friendly output. + +> **[Spotless](https://github.com/diffplug/spotless)** β˜… 5.6k Apache-2.0 🟒
A versatile code formatter for Gradle and Maven that enforces multiple styles (including Google and Palantir) across Java and other languages. + +
+ +
+Code Generators 18 projects + +_Tools that generate patterns for repetitive code in order to reduce verbosity and error-proneness._ + +> **[Auto](https://github.com/google/auto)** β˜… 10.6k Apache-2.0 🟒
Generates factory, service, and value classes. + +> **[Avaje HTTP](https://github.com/avaje/avaje-http)** β˜… 96 Apache-2.0 🟒
Generates HTTP server adapters and declarative clients, with a lightweight JDK HTTP client. + +> **[Bootify](https://bootify.io)**
Browser-based Spring Boot app generation with JPA model and REST API. + +> **[Chocotea](https://github.com/cleopatra27/chocotea)** β˜… 48 Apache-2.0 πŸ”΄
Generates postman collection, environment and integration tests from java code. + +> **[CRUDGen](https://github.com/bariskokulu/CRUDGen)** β˜… 11 Apache-2.0 🟒
Compile-time annotation processor generating CRUD layers, DTOs, JSON Patch, and custom HTTP endpoints for Spring Boot. + +> **[EasyEntityToDTO](https://github.com/Marcel091004/EasyEntityToDTO)** β˜… 11 MIT 🟠
Annotation processor for automatic DTO and Mapper generation with zero boilerplate. + +> **[Geci](https://github.com/verhas/javageci)** β˜… 138 Apache-2.0 🟠
Discovers files that need generated code, updates automatically and writes to the source with a convenient API. + +> **[Immutables](https://github.com/immutables/immutables)** β˜… 3.6k Apache-2.0 🟒
Annotation processors to generate simple, safe and consistent value objects. + +> **[J2ObjC](https://github.com/google/j2objc)** β˜… 6.0k 🟒
Java-to-Objective-C translator for porting Android libraries to iOS. + +> **[JHipster](https://github.com/jhipster/generator-jhipster)** β˜… 22.4k Apache-2.0 🟒
Yeoman source code generator for Spring Boot and AngularJS. + +> **[Joda-Beans](https://github.com/JodaOrg/joda-beans)** β˜… 150 Apache-2.0 🟠
Small framework that adds queryable properties to Java, enhancing JavaBeans. + +> **[JPA Buddy](https://www.jpa-buddy.com)**
Plugin for IntelliJ IDEA. Provides visual tools for generating JPA entities, Spring Data JPA repositories, Liquibase changelogs and SQL scripts. Offers automatic Liquibase/Flyway script generation by comparing model to DB, and reverse engineering JPA entities from DB tables. + +> **[jsonschema2pojo](https://github.com/joelittlejohn/jsonschema2pojo)** β˜… 6.4k Apache-2.0 🟠
Generates Java types from JSON Schema or example JSON. + +> **[JSpecify Package-Info Generator](https://github.com/bcaillard/jspecify-packageinfo-generator)** β˜… 4 Apache-2.0 🟠
Maven plugin that automatically generates package-info.java files with JSpecify annotations (@NullMarked and @NullUnmarked), helping you manage nullness boundaries in your Java projects without manual boilerplate. + +> **[Lombok](https://github.com/projectlombok/lombok)** β˜… 13.5k 🟒
Code generator that aims to reduce verbosity. + +> **[Record-Builder](https://github.com/Randgalt/record-builder)** β˜… 925 Apache-2.0 🟒
Companion builder class, withers and templates for Java records. + +> **[Spring CRUD Generator](https://github.com/mzivkovicdev/spring-crud-generator)** β˜… 38 Apache-2.0 🟒
Maven plugin for generating Spring Boot CRUD applications from YAML/JSON specifications. + +> **[Telosys](https://www.telosys.org/)** β˜… 212 LGPL-3.0 🟠
Java code-generation toolkit with a CLI and model-driven template engine. + +
+ +
+Compiler-compiler 3 projects + +_Frameworks that help to create parsers, interpreters or compilers._ + +> **[ANTLR](https://github.com/antlr/antlr4)** β˜… 19.0k BSD-3-Clause 🟠
Complex full-featured framework for top-down parsing. + +> **[JavaCC](https://github.com/javacc/javacc)** β˜… 1.3k BSD-3-Clause πŸ”΄
Parser generator that generates top-down parsers. Allows lexical state switching and permits extended BNF specifications. + +> **[JFlex](https://github.com/jflex-de/jflex)** β˜… 630 πŸ”΄
Lexical analyzer generator. + +
+ +
+Computer Vision 3 projects + +_Libraries which seek to gain high level information from images and videos._ + +> **[BoofCV](https://github.com/lessthanoptimal/BoofCV)** β˜… 1.2k 🟒
Library for image processing, camera calibration, tracking, SFM, MVS, 3D vision, QR Code and much more. + +> **[ImageJ](https://github.com/imagej/ImageJ)** β˜… 775 🟒
Medical image processing application with an API. + +> **[JavaCV](https://github.com/bytedeco/javacv)** β˜… 8.3k 🟒
Java interface to OpenCV, FFmpeg, and much more. + +
+ +
+Configuration 14 projects + +_Libraries that provide external configuration._ + +> **[avaje config](https://github.com/avaje/avaje-config)** β˜… 108 Apache-2.0 🟒
Loads yaml and properties files, supports dynamic configuration, plugins, file-watching and config event listeners. + +> **[centraldogma](https://github.com/line/centraldogma)** β˜… 665 Apache-2.0 🟒
Highly-available version-controlled service configuration repository based on Git, ZooKeeper and HTTP/2. + +> **[ClearConfig](https://github.com/japgolly/clear-config-java)** β˜… 9 Apache-2.0 🟒
Type-safe, composable configuration library with a focus on runtime clarity. + +> **[config](https://github.com/lightbend/config)** β˜… 6.3k 🟒
Configuration library supporting Java properties, JSON or its human optimized superset HOCON. + +> **[Configurate](https://github.com/SpongePowered/Configurate)** β˜… 466 Apache-2.0 🟒
Configuration library with support for various configuration formats and transformations. + +> **[dotenv](https://github.com/shyiko/dotenv)** β˜… 51 πŸ”΄
Twelve-factor configuration library which uses environment-specific files. + +> **[Externalized Properties](https://github.com/joel-jeremy/externalized-properties)** β˜… 47 Apache-2.0 🟠
Simple, lightweight, yet powerful configuration library which supports resolution of properties from external sources such as files, databases, git repositories, and any custom sources, plus an extensible post-processing/conversion mechanism. + +> **[Gestalt](https://github.com/gestalt-config/gestalt)** β˜… 102 Apache-2.0 🟒
Gestalt offers a comprehensive solution to the challenges of configuration management. It allows you to source configuration data from multiple inputs, merge them intelligently, and present them in a structured, type-safe manner. + +> **[ini4j](https://ini4j.sourceforge.net)**
Provides an API for handling Windows' INI files. + +> **[KAConf](https://github.com/mariomac/kaconf)** β˜… 63 Apache-2.0 πŸ”΄
Annotation-based configuration system for Java and Kotlin. + +> **[microconfig](https://github.com/microconfig/microconfig)** β˜… 320 Apache-2.0 πŸ”΄
Configuration system designed for microservices which helps to separate configuration from code. The configuration for different services can have common and specific parts and can be dynamically distributed. + +> **[NightConfig](https://github.com/TheElectronWill/night-config)** β˜… 283 LGPL-3.0 🟒
Configuration library supporting TOML, YAML, HOCON, JSON and in-memory formats. + +> **[owner](https://github.com/matteobaccan/owner)** β˜… 939 BSD-3-Clause 🟒
Reduces boilerplate of properties. + +> **[sealed-env](https://github.com/davidalmeidac/sealed-env)** β˜… 9 MIT 🟒
Encrypts environment files with a shared Node.js and Java/Spring Boot format plus optional TOTP unsealing. + +
+ +
+Constraint Satisfaction Problem Solver 3 projects + +_Libraries that help with implementing optimization and satisfiability problems._ + +> **[Choco](https://github.com/chocoteam/choco-solver)** β˜… 771 BSD-3-Clause 🟒
Off-the-shelf constraint satisfaction problem solver that uses constraint programming techniques. + +> **[JaCoP](https://github.com/radsz/jacop)** β˜… 235 🟠
Includes an interface for the FlatZinc language, enabling it to execute MiniZinc models. (AGPL-3.0) + +> **[Timefold](https://github.com/TimefoldAI/timefold-solver)** β˜… 1.7k Apache-2.0 🟒
Flexible solver with Spring/Quarkus support and quickstarts for the Vehicle Routing Problem, Maintenance Scheduling, Employee Shift Scheduling and much more. + +
+ +
+CSV 3 projects + +_Frameworks and libraries that simplify reading/writing CSV data._ + +> **[FastCSV](https://github.com/osiegmar/FastCSV)** β˜… 690 MIT 🟒
Performance-optimized, dependency-free and RFC 4180 compliant. + +> **[jackson-dataformat-csv](https://github.com/FasterXML/jackson-dataformats-text)** β˜… 454 Apache-2.0 🟒
Jackson extension for reading and writing CSV. + +> **[opencsv](https://opencsv.sourceforge.net)**
Simple CSV parser. + +
+ +
+Data Processing 8 projects + +_Tools for batch, stream, table and data-transformation workloads._ + +> **[Apache Flink](https://github.com/apache/flink)** β˜… 26.2k Apache-2.0 🟒
Fast, reliable, large-scale data processing engine. + +> **[Apache Storm](https://github.com/apache/storm)** β˜… 6.7k Apache-2.0 🟒
Realtime computation system. + +> **[easy-batch](https://github.com/j-easy/easy-batch)** β˜… 622 MIT πŸ”΄
Set up batch jobs with simple processing pipelines. Records are read in sequence from a data source, processed in pipeline and written in batches to a data sink. + +> **[Embulk](https://github.com/embulk/embulk)** β˜… 1.8k Apache-2.0 🟒
Bulk data loader that helps data transfer between various databases, storages, file formats, and cloud services. + +> **[OpenRefine](https://github.com/OpenRefine/OpenRefine)** β˜… 11.9k BSD-3-Clause 🟒
Tool for working with messy data: cleaning, transforming, extending it with web services and linking it to databases. + +> **[Siddhi](https://github.com/siddhi-io/siddhi)** β˜… 1.6k Apache-2.0 🟒
Cloud native streaming and complex event processing engine. + +> **[Smooks](https://github.com/smooks/smooks)** β˜… 417 🟠
Framework for fragment-based message processing. (Apache-2.0 OR LGPL-3.0-or-later) + +> **[Tablesaw](https://github.com/jtablesaw/tablesaw)** β˜… 3.8k Apache-2.0 🟒
Includes a data-frame, an embedded column store, and hundreds of methods to transform, summarize, or filter data. + +
+ +
+Data Structures 5 projects + +_Efficient and specific data structures._ + +> **[CQEngine Next](https://github.com/MSaifAsif/cqengine-next)** β˜… 17 Apache-2.0 🟒
Provides indexed, SQL-like queries over Java collections. + +> **[HashSmith](https://github.com/bluuewhale/hash-smith)** β˜… 106 MIT 🟠
Hash map and set implementations using SwissTable-style SWAR/SIMD control-byte probing, optimized for memory efficiency. + +> **[Persistent Collection](https://github.com/hrldcpr/pcollections)** β˜… 787 πŸ”΄
Persistent and immutable analogue of the Java Collections Framework. + +> **[RoaringBitmap](https://github.com/RoaringBitmap/RoaringBitmap)** β˜… 3.9k Apache-2.0 🟒
Fast and efficient compressed bitmap. + +> **[Wormhole4j](https://github.com/komamitsu/wormhole4j)** β˜… 8 Apache-2.0 🟒
High-performance sorted map with fast range scans and thread-safe concurrent access, based on the Wormhole index structure. + +
+ +
+Database 49 projects + +_Everything that simplifies interactions with the database._ + +> **[Actual Schema Gradle Plugin](https://github.com/YRashid/actual-schema-gradle-plugin)** β˜… 18 Apache-2.0 🟒
Generates PostgreSQL schema DDL from Liquibase migrations using Testcontainers. + +> **[Apache Calcite](https://github.com/apache/calcite)** β˜… 5.2k Apache-2.0 🟒
Dynamic data management framework. It contains many of the pieces that comprise a typical database management system. + +> **[Apache Cassandra](https://github.com/apache/cassandra)** β˜… 10.0k Apache-2.0 🟒
Distributed wide-column database with linear scalability and fault tolerance. + +> **[Apache Doris](https://github.com/apache/doris)** β˜… 15.7k Apache-2.0 🟒
Distributed SQL database for real-time analytics. + +> **[Apache Drill](https://github.com/apache/drill)** β˜… 2.0k Apache-2.0 🟒
Distributed, schema on-the-fly, ANSI SQL query engine for Big Data exploration. + +> **[Apache Phoenix](https://github.com/apache/phoenix)** β˜… 1.1k Apache-2.0 🟒
High-performance relational database layer over HBase for low-latency applications. + +> **[Apache ShardingSphere](https://github.com/apache/shardingsphere)** β˜… 20.8k Apache-2.0 🟒
Distributed SQL transaction & query engine that allows for data sharding, scaling, encryption, and more on any database. + +> **[ArangoDB](https://github.com/arangodb/arangodb-java-driver)** β˜… 209 Apache-2.0 🟒
ArangoDB Java driver. + +> **[ArcadeDB](https://github.com/ArcadeData/arcadedb)** β˜… 1.1k Apache-2.0 🟒
Multi-model database supporting graphs, documents, key-value, time series, and vector embeddings with SQL, Cypher, Gremlin, MongoDB, and Redis API compatibility. + +> **[Chronicle Map](https://github.com/OpenHFT/Chronicle-Map)** β˜… 3.0k Apache-2.0 🟒
Efficient, in-memory (opt. persisted to disk), off-heap key-value store. + +> **[ClickHouse Java](https://github.com/ClickHouse/clickhouse-java)** β˜… 1.6k Apache-2.0 🟒
Java clients and JDBC driver for ClickHouse. + +> **[CosId](https://github.com/Ahoo-Wang/CosId)** β˜… 640 Apache-2.0 🟒
Universal, flexible, high-performance distributed ID generator. + +> **[Debezium](https://github.com/debezium/debezium)** β˜… 13.0k Apache-2.0 🟒
Low latency data streaming platform for change data capture. + +> **[druid](https://github.com/apache/druid)** β˜… 14.0k Apache-2.0 🟒
High-performance, column-oriented, distributed data store. + +> **[eXist](https://github.com/eXist-db/exist)** β˜… 466 LGPL-2.1 🟒
NoSQL document database and application platform. + +> **[FlexyPool](https://github.com/vladmihalcea/flexy-pool)** β˜… 1.2k Apache-2.0 🟠
Brings metrics and failover strategies to the most common connection pooling solutions. + +> **[Flyway](https://github.com/flyway/flyway)** β˜… 10.0k Apache-2.0 🟒
Simple database migration tool. + +> **[H2](https://github.com/h2database/h2database)** β˜… 4.6k 🟒
Small SQL database notable for its in-memory functionality. + +> **[HikariCP](https://github.com/brettwooldridge/HikariCP)** β˜… 21.2k Apache-2.0 🟒
High-performance JDBC connection pool. + +> **[HSQLDB](https://hsqldb.org/)**
HyperSQL 100% Java database. + +> **[JanusGraph](https://github.com/JanusGraph/janusgraph)** β˜… 5.8k 🟒
Distributed graph database supporting pluggable storage and indexing backends. + +> **[JDBI](https://github.com/jdbi/jdbi)** β˜… 2.1k Apache-2.0 🟒
Convenient abstraction of JDBC. + +> **[Jedis](https://github.com/redis/jedis)** β˜… 12.3k MIT 🟒
Java client for Redis with synchronous, asynchronous and cluster APIs. + +> **[jetcd](https://github.com/etcd-io/jetcd)** β˜… 1.2k Apache-2.0 🟒
Java client for etcd v3. + +> **[Jinq](https://github.com/my2iu/Jinq)** β˜… 661 πŸ”΄
Typesafe database queries via symbolic execution of Java 8 Lambdas (on top of JPA or jOOQ). + +> **[jOOQ](https://github.com/jOOQ/jOOQ)** β˜… 6.8k 🟒
Generates typesafe code based on SQL schema. + +> **[Lettuce](https://github.com/redis/lettuce)** β˜… 5.8k MIT 🟒
Lettuce is a scalable Redis client for building non-blocking Reactive applications. + +> **[Liquibase](https://github.com/liquibase/liquibase)** β˜… 5.6k 🟒
Database-independent library for tracking, managing and applying database schema changes. + +> **[MapDB](https://github.com/jankotek/mapdb)** β˜… 5.1k Apache-2.0 🟒
Embedded database engine that provides concurrent collections backed on disk or in off-heap memory. + +> **[MariaDB4j](https://github.com/vorburger/MariaDB4j)** β˜… 16 Apache-2.0 🟠
Launcher for MariaDB that requires no installation or external dependencies. + +> **[Modality](https://github.com/arkanovicz/modality)** β˜… 16 Apache-2.0 🟒
Lightweight ORM with database reverse engineering features. + +> **[MongoDB Java Driver](https://github.com/mongodb/mongo-java-driver)** β˜… 2.7k Apache-2.0 🟒
Official synchronous, asynchronous and reactive Java drivers for MongoDB. + +> **[ObjectBox](https://github.com/objectbox/objectbox-java)** β˜… 4.6k Apache-2.0 🟒
Embedded object and vector database for Java and Android. + +> **[Open J Proxy](https://github.com/Open-J-Proxy/ojp)** β˜… 219 Apache-2.0 🟒
Type 3 JDBC driver and Layer 7 proxy server for decoupling applications from relational database connection management. + +> **[OpenDJ](https://github.com/OpenIdentityPlatform/OpenDJ)** β˜… 435 🟒
LDAPv3 compliant directory service, developed for the Java platform, providing a high performance, highly available, and secure store for the identities. + +> **[Presto](https://github.com/prestodb/presto)** β˜… 16.7k Apache-2.0 🟒
Distributed SQL query engine for large data sources. + +> **[Querydsl](https://github.com/querydsl/querydsl)** β˜… 5.0k Apache-2.0 🟒
Typesafe unified queries. + +> **[QueryStream](https://github.com/querystream/querystream)** β˜… 21 Apache-2.0 πŸ”΄
Build JPA Criteria queries using a Stream-like API. + +> **[QuestDB](https://github.com/questdb/questdb)** β˜… 17.2k Apache-2.0 🟒
High-performance SQL database for time series. Supports InfluxDB line protocol, PostgreSQL wire protocol, and REST. + +> **[Realm](https://github.com/realm/realm-java)** β˜… 11.5k Apache-2.0 🟠
Mobile database to run directly inside phones, tablets or wearables. + +> **[Redisson](https://github.com/redisson/redisson)** β˜… 24.4k Apache-2.0 🟒
Allows for distributed and scalable data structures on top of a Redis server. + +> **[requery](https://github.com/requery/requery)** β˜… 3.1k Apache-2.0 🟠
Modern, lightweight but powerful object mapping and SQL generator. Easily map to or create databases, or perform queries and updates from any Java-using platform. + +> **[SchemaCrawler](https://github.com/schemacrawler/SchemaCrawler)** β˜… 1.8k 🟒
Discovers, documents and diagrams relational database schemas from Java, build tools and the command line. + +> **[Spring Data Dynamic Query](https://github.com/tdilber/spring-data-dynamic-query)** β˜… 40 Apache-2.0 🟠
Unified dynamic query interface for Spring Data JPA, MongoDB, and Elasticsearch, enabling advanced JOIN(s), OR logic, scoped conditions, powerful projections and advanced features with zero boilerplate. + +> **[Spring Data JPA MongoDB Expressions](https://github.com/mhewedy/spring-data-jpa-mongodb-expressions)** β˜… 104 Apache-2.0 🟠
Allows you to use MongoDB query language to query your relational database. + +> **[StarRocks](https://github.com/StarRocks/starrocks)** β˜… 12.0k Apache-2.0 🟒
Distributed SQL query engine for real-time analytics and data lakehouses. + +> **[Trino](https://github.com/trinodb/trino)** β˜… 13.1k Apache-2.0 🟒
Distributed SQL query engine for big data. + +> **[Vibur DBCP](https://github.com/vibur/vibur-dbcp)** β˜… 124 Apache-2.0 πŸ”΄
JDBC connection pool library with advanced performance monitoring capabilities. + +> **[Xodus](https://github.com/JetBrains/xodus)** β˜… 1.3k Apache-2.0 🟒
Highly concurrent transactional schema-less and ACID-compliant embedded database. + +
+ +
+Date and Time 4 projects + +_Libraries related to handling date and time._ + +> **[iCal4j](https://github.com/ical4j/ical4j)** β˜… 836 BSD-3-Clause 🟒
Parse and build iCalendar [RFC 5545](https://tools.ietf.org/html/rfc5545) data models. + +> **[Jollyday](https://github.com/focus-shift/jollyday)** β˜… 134 Apache-2.0 🟒
Determines the holidays for a given year, country/name and eventually state/region. + +> **[ThreeTen-Extra](https://github.com/ThreeTen/threeten-extra)** β˜… 423 BSD-3-Clause 🟒
Additional date-time classes that complement those in JDK 8. + +> **[Time4J](https://github.com/MenoData/Time4J)** β˜… 471 LGPL-2.1 πŸ”΄
Advanced date and time library. + +
+ +
+Decentralization 3 projects + +_Libraries that handle decentralization tasks._ + +> **[bitcoinj](https://github.com/bitcoinj/bitcoinj)** β˜… 5.2k Apache-2.0 🟒
Library for working with the Bitcoin protocol and network. + +> **[java-tron](https://github.com/tronprotocol/java-tron)** β˜… 4.1k LGPL-3.0 🟒
Implementation of the Tron Protocol, whic utilizes blockchains to develop decentralized applications. + +> **[web3j](https://github.com/LFDT-web3j/web3j)** β˜… 5.4k 🟒
Java and Android library for integrating with Ethereum-compatible blockchains. + +
+ +
+Decompilation 5 projects + +_Libraries for decompiling JVM bytecode._ + +> **[CFR](https://github.com/leibnitz27/cfr)** β˜… 2.6k MIT 🟒
Java decompiler focused on modern language features. + +> **[Fernflower](https://github.com/JetBrains/fernflower)** β˜… 4.4k Apache-2.0 🟒
Java decompiler with broad JVM bytecode support. + +> **[jadx](https://github.com/skylot/jadx)** β˜… 49.9k Apache-2.0 🟒
Dex-to-Java decompiler with command-line and graphical interfaces. + +> **[transformer-api](https://github.com/nbauma109/transformer-api)** β˜… 3 Apache-2.0 🟒
Unified API that exposes multiple decompilers through one in-memory transformation interface. + +> **[Vineflower](https://github.com/Vineflower/vineflower)** β˜… 2.3k Apache-2.0 🟒
Modern maintained fork of Fernflower. + +
+ +
+Dependency Injection 7 projects + +_Libraries that help to realize the [Inversion of Control](https://en.wikipedia.org/wiki/Inversion_of_control) paradigm._ + +> **[Apache DeltaSpike](https://github.com/apache/deltaspike)** β˜… 154 Apache-2.0 🟒
CDI extension framework. + +> **[Avaje Inject](https://github.com/avaje/avaje-inject)** β˜… 314 Apache-2.0 🟒
Microservice-focused compile-time injection framework without reflection. + +> **[Dagger](https://github.com/google/dagger)** β˜… 17.7k Apache-2.0 🟒
Compile-time injection framework without reflection. + +> **[Dimension-DI](https://github.com/akardapolov/dimension-di)** β˜… 19 Apache-2.0 🟒
JSR-330 runtime dependency injection using the JDK Class-File API. + +> **[Governator](https://github.com/Netflix/governator)** β˜… 829 Apache-2.0 🟠
Extensions and utilities that enhance Google Guice. + +> **[Guice](https://github.com/google/guice)** β˜… 12.7k Apache-2.0 🟒
Lightweight and opinionated framework that completes Dagger. + +> **[HK2](https://github.com/eclipse-ee4j/glassfish-hk2)** β˜… 95 🟠
Lightweight and dynamic dependency injection framework. + +
+ +
+Development 12 projects + +_Augmentation of the development process at a fundamental level._ + +> **[AspectJ](https://github.com/eclipse-aspectj/aspectj)** β˜… 392 🟠
Seamless aspect-oriented programming extension. + +> **[Faux Pas](https://github.com/zalando/faux-pas)** β˜… 143 MIT πŸ”΄
Library that simplifies error handling by circumventing the issue that none of the functional interfaces in the Java Runtime is allowed by default to throw checked exceptions. + +> **[Ghidra](https://github.com/NationalSecurityAgency/ghidra)** β˜… 71.8k Apache-2.0 🟒
Extensible software reverse-engineering framework with Java APIs and scripting. + +> **[HotswapAgent](https://github.com/HotswapProjects/HotswapAgent)** β˜… 2.6k GPL-2.0 🟒
Unlimited runtime class and resource redefinition. + +> **[JavaParser](https://github.com/javaparser/javaparser)** β˜… 6.1k 🟒
Parse, modify and generate Java code. + +> **[Jctx](https://github.com/Shashwat-Gupta57/jctx)** β˜… 6 MIT 🟠
Reads a Java project and generates a structured context file so AI tools can understand and help plan the codebase. + +> **[JGit](https://github.com/eclipse-jgit/jgit)** β˜… 414 🟒
Lightweight, pure Java library implementing the Git version control system. + +> **[Manifold](https://github.com/manifold-systems/manifold)** β˜… 2.8k Apache-2.0 🟒
Re-energizes Java with powerful features like type-safe metaprogramming, structural typing and extension methods. + +> **[NoException](https://github.com/robertvazan/noexception)** β˜… 130 Apache-2.0 πŸ”΄
Allows checked exceptions in functional interfaces and converts exceptions to Optional return. + +> **[RR4J](https://github.com/Kartikvk1996/RR4J)** β˜… 25 GPL-3.0 πŸ”΄
RR4J is a tool that records java bytecode execution and later allows developers to replay locally. + +> **[SneakyThrow](https://github.com/rainerhahnekamp/sneakythrow)** β˜… 81 MIT πŸ”΄
Ignores checked exceptions without bytecode manipulation. Can also be used inside Java 8 stream operations. + +> **[Tail](https://github.com/nrktkt/tail)** β˜… 30 Unlicense πŸ”΄
Enable infinite recursion using tail call optimization. + +
+ +
+Distributed Applications 10 projects + +_Libraries and frameworks for writing distributed and fault-tolerant applications._ + +> **[Apache Geode](https://github.com/apache/geode)** β˜… 2.4k Apache-2.0 🟒
In-memory data management system that provides reliable asynchronous event notifications and guaranteed message delivery. + +> **[Apache ZooKeeper](https://github.com/apache/zookeeper)** β˜… 12.8k Apache-2.0 🟒
Coordination service with distributed configuration, synchronization, and naming registry for large distributed systems. + +> **[Axon](https://github.com/AxonIQ/AxonFramework)** β˜… 3.6k Apache-2.0 🟒
Framework for creating CQRS applications. + +> **[Curator Framework](https://github.com/apache/curator)** β˜… 3.2k Apache-2.0 🟒
High-level API for Apache ZooKeeper. + +> **[Dropwizard Circuit Breaker](https://github.com/mtakaki/dropwizard-circuitbreaker)** β˜… 46 GPL-2.0 🟠
Circuit breaker design pattern for Dropwizard. + +> **[Failsafe](https://github.com/failsafe-lib/failsafe)** β˜… 4.3k Apache-2.0 🟠
Simple failure handling with retries and circuit breakers. + +> **[Hazelcast](https://github.com/hazelcast/hazelcast)** β˜… 6.6k 🟒
Highly scalable in-memory datagrid with a free open-source version. + +> **[JGroups](https://github.com/belaban/JGroups)** β˜… 1.1k Apache-2.0 🟒
Toolkit for reliable messaging and cluster creation. + +> **[resilience4j](https://github.com/resilience4j/resilience4j)** β˜… 10.7k Apache-2.0 🟒
Functional fault tolerance library. + +> **[ScaleCube Services](https://github.com/scalecube/scalecube-services)** β˜… 639 Apache-2.0 🟒
Embeddable Cluster-Membership library based on SWIM and gossip protocol. + +
+ +
+Distributed Transactions 4 projects + +_Distributed transactions provide a mechanism for ensuring consistency of data updates in the presence of concurrent access and partial failures._ + +> **[Atomikos](https://github.com/atomikos/transactions-essentials)** β˜… 484 🟒
Provides transactions for REST, SOA and microservices with support for JTA and XA. + +> **[Bitronix](https://github.com/bitronix/btm)** β˜… 431 Apache-2.0 🟠
Simple but complete implementation of the JTA 1.1 API. + +> **[Narayana](https://github.com/jbosstm/narayana)** β˜… 265 Apache-2.0 🟒
Provides support for traditional ACID and compensation transactions, also complies with JTA, JTS and other standards. + +> **[Seata](https://github.com/apache/incubator-seata)** β˜… 26.0k Apache-2.0 🟒
Delivers high performance and easy to use distributed transaction services under a microservices architecture. + +
+ +
+Distribution 13 projects + +_Tools that handle the distribution of applications in native formats._ + +> **[Artipie](https://github.com/artipie/artipie)** β˜… 688 MIT 🟒
Binary artifact management toolkit which hosts them on the file system or S3. + +> **[Boxfuse](https://boxfuse.com)**
Deployment of JVM applications to AWS using the principles of immutable infrastructure. + +> **[Central Repository](https://search.maven.org)**
Largest binary component repository available as a free service to the open-source community. Default used by Apache Maven, and available in all other build tools. + +> **[Cloudsmith](https://cloudsmith.io)**
Fully managed package management SaaS with support for Maven/Gradle/SBT with a free tier. + +> **[Getdown](https://github.com/threerings/getdown)** β˜… 529 🟒
System for deploying Java applications to end-user computers and keeping them up to date. Developed as an alternative to Java Web Start. + +> **[IzPack](https://github.com/izpack/izpack)** β˜… 353 Apache-2.0 🟒
Setup authoring tool for cross-platform deployments. + +> **[JavaPackager](https://github.com/javapackager/JavaPackager)** β˜… 1.2k GPL-3.0 🟠
Maven and Gradle plugin which provides an easy way to package Java applications in native Windows, macOS or GNU/Linux executables, and generate installers for them. + +> **[jDeploy](https://github.com/shannah/jdeploy)** β˜… 415 Apache-2.0 🟒
Deploy desktop apps as native Mac, Windows or Linux bundles. + +> **[jlink.online](https://github.com/AdoptOpenJDK/jlink.online)** β˜… 51 Apache-2.0 🟒
Builds optimized runtimes over HTTP. + +> **[Nexus](https://github.com/sonatype/nexus-public)** β˜… 2.6k EPL-1.0 🟒
Binary management with proxy and caching capabilities. + +> **[Nuts](https://github.com/thevpc/nuts)** β˜… 157 🟒
Installs and runs Java applications from Maven repositories, reusing descriptors and provisioning required JDKs. + +> **[packr](https://github.com/libgdx/packr)** β˜… 2.6k Apache-2.0 πŸ”΄
Packs JARs, assets and the JVM for native distribution on Windows, Linux and macOS. + +> **[really-executable-jars-maven-plugin](https://github.com/brianm/really-executable-jars-maven-plugin)** β˜… 136 Apache-2.0 🟠
Maven plugin for making self-executing JARs. + +
+ +
+Document Processing 7 projects + +_Libraries that assist with processing office document formats._ + +> **[Apache Tika](https://github.com/apache/tika)** β˜… 3.9k Apache-2.0 🟒
Detects and extracts text and metadata from a wide range of document formats. + +> **[commonmark-java](https://github.com/commonmark/commonmark-java)** β˜… 2.7k BSD-2-Clause 🟒
Parses and renders CommonMark-compatible Markdown. + +> **[documents4j](https://github.com/documents4j/documents4j)** β˜… 585 Apache-2.0 🟠
API for document format conversion using third-party converters such as MS Word. + +> **[docx4j](https://github.com/plutext/docx4j)** β˜… 2.4k 🟒
Create and manipulate Microsoft Open XML files. + +> **[html-to-markdown](https://github.com/xberg-io/html-to-markdown)** β˜… 822 MIT 🟒
Converts HTML to CommonMark-compatible Markdown through a Java binding. + +> **[JQuick Excel](https://github.com/paohaijiao/jquick-excel)** β˜… 130 🟒
Configures Excel import, export, validation, formulas and charts through a declarative XML DSL. + +> **[xberg](https://github.com/xberg-io/xberg)** β˜… 8.8k MIT 🟒
Extracts text, tables and metadata from PDFs, Office documents, images and other formats through a Java binding. + +
+ +
+Feature Flags 5 projects + +_Libraries and SDKs for evaluating and managing feature flags._ + +> **[FF4J](https://github.com/ff4j/ff4j)** β˜… 1.4k Apache-2.0 🟒
Feature Flags for Java. + +> **[OpenFeature Java SDK](https://github.com/open-feature/java-sdk)** β˜… 127 Apache-2.0 🟒
Vendor-neutral API for evaluating feature flags in Java applications. + +> **[Rollgate Java SDK](https://github.com/rollgate/sdks/tree/main/packages/sdk-java)** β˜… 3 MIT 🟒
Java SDK for evaluating Rollgate feature flags with real-time configuration updates. + +> **[Togglz](https://github.com/togglz/togglz)** β˜… 1.0k Apache-2.0 🟒
Implementation of the Feature Toggles pattern. + +> **[Unleash Java SDK](https://github.com/Unleash/unleash-java-sdk)** β˜… 137 Apache-2.0 🟒
Java client SDK for the Unleash feature management platform. + +
+ +
+Financial 8 projects + +_Libraries related to the financial domain._ + +> **[Cassandre](https://github.com/cassandre-tech/cassandre-trading-bot)** β˜… 660 GPL-3.0 πŸ”΄
Trading bot framework. + +> **[Joda-Money](https://github.com/JodaOrg/joda-money)** β˜… 679 Apache-2.0 🟠
Basic currency and money classes and algorithms not provided by the JDK. + +> **[OpenGamma Strata](https://github.com/OpenGamma/Strata)** β˜… 952 Apache-2.0 🟒
Analytics and market risk library for financial products. + +> **[Philadelphia](https://github.com/paritytrading/philadelphia)** β˜… 344 Apache-2.0 🟒
Low-latency financial information exchange. + +> **[Stripe](https://github.com/stripe/stripe-java)** β˜… 995 MIT 🟒
Integration with the Stripe API. + +> **[ta4j](https://github.com/ta4j/ta4j)** β˜… 2.5k 🟒
Library for technical analysis. + +> **[Wickra](https://github.com/wickra-lib/wickra)** β˜… 36 Apache-2.0 🟒
Technical-analysis library with 514 streaming O(1)-per-tick indicators on a native Rust core, on Maven Central as org.wickra:wickra; more indicators and incremental updates than the pure-Java ta4j. + +> **[XChange](https://github.com/knowm/XChange)** β˜… 4.1k MIT 🟒
Consistent Java API for market data and trading across cryptocurrency exchanges. + +
+ +
+Flat File 3 projects + +_Frameworks and libraries for reading and writing fixed-length and delimited flat files._ + +> **[BeanIO](https://github.com/beanio/beanio)** β˜… 68 Apache-2.0 πŸ”΄
Maps flat files of fixed-length or delimited records to and from Java beans using XML or annotation configuration. + +> **[fixedformat4j](https://github.com/jeyben/fixedformat4j)** β˜… 52 Apache-2.0 🟒
Annotation-driven mapping of fixed-width flat files to and from POJOs and Java records. + +> **[Flatpack](https://github.com/Appendium/flatpack)** β˜… 64 Apache-2.0 🟠
Parses and writes delimited and fixed-length flat files with optional column-mapping definitions. + +
+ +
+Formal Verification 6 projects + +_Formal-methods tools: proof assistants, model checking, symbolic execution, etc._ + +> **[Checker Framework](https://github.com/typetools/checker-framework)** β˜… 1.1k 🟒
Pluggable type systems. Includes nullness types, physical units, immutability types and more. (GPL-2.0-only WITH Classpath-exception-2.0) + +> **[Daikon](https://github.com/codespecs/daikon)** β˜… 255 🟒
Detects likely program invariants and generates JML specs based on those invariants. + +> **[Java Path Finder (JPF)](https://github.com/javapathfinder/jpf-core)** β˜… 615 🟒
JVM formal verification tool containing a model checker and more. Created by NASA. + +> **[JMLOK 2.0](https://massoni.computacao.ufcg.edu.br/home/jmlok)**
Detects inconsistencies between code and JML specification through feedback-directed random tests generation, and suggests a likely cause for each nonconformance detected. (GPL-3.0-only) + +> **[KeY](https://github.com/KeYProject/key)** β˜… 88 🟒
Formal software development tool that aims to integrate design, implementation, formal specification, and formal verification of object-oriented software as seamlessly as possible. Uses JML for specification and symbolic execution for verification. (GPL-2.0-or-later) + +> **[OpenJML](https://github.com/OpenJML/OpenJML)** β˜… 182 🟒
Translates JML specifications into SMT-LIB format and passes the proof problems implied by the program to backend solvers. (GPL-2.0-only) + +
+ +
+Functional Programming 8 projects + +_Libraries that facilitate functional programming._ + +> **[Fugue](https://bitbucket.org/atlassian/fugue)**
Functional extensions to Guava. + +> **[Functional Java](https://github.com/functionaljava/functionaljava)** β˜… 1.6k πŸ”΄
Implements numerous basic and advanced programming abstractions that assist composition-oriented development. + +> **[jOOΞ»](https://github.com/jOOQ/jOOL)** β˜… 2.1k Apache-2.0 πŸ”΄
Extension to Java 8 that aims to fix gaps in lambda by providing numerous missing types and a rich set of sequential Stream API additions. + +> **[Packrat](https://github.com/jhspetersson/packrat)** β˜… 29 Apache-2.0 🟒
Gatherers library for Java Stream API. Gatherers can enhance streams with custom intermediate operations. + +> **[Parallel Collectors](https://github.com/pivovarit/parallel-collectors)** β˜… 680 Apache-2.0 🟒
Stream API Collectors for parallel processing with custom thread pools, designed for I/O-heavy workloads. + +> **[protonpack](https://github.com/poetix/protonpack)** β˜… 487 MIT 🟒
Collection of stream utilities. + +> **[StreamEx](https://github.com/amaembo/streamex)** β˜… 2.3k Apache-2.0 🟒
Enhances Java 8 Streams. + +> **[Vavr](https://github.com/vavr-io/vavr)** β˜… 6.2k Apache-2.0 🟒
Functional component library that provides persistent data types and functional control structures. + +
+ +
+Game Development 9 projects + +_Frameworks that support the development of games._ + +> **[FXGL](https://github.com/AlmasB/FXGL)** β˜… 4.8k MIT 🟒
JavaFX Game Development Framework. + +> **[input4j](https://github.com/gurkenlabs/input4j)** β˜… 25 MIT 🟒
Lightweight, cross-platform library for gamepad and joystick input handling. + +> **[JBox2D](https://github.com/jbox2d/jbox2d)** β˜… 1.1k BSD-2-Clause πŸ”΄
Port of the renowned C++ 2D physics engine. + +> **[jMonkeyEngine](https://github.com/jMonkeyEngine/jmonkeyengine)** β˜… 4.3k BSD-3-Clause 🟒
Game engine for modern 3D development. + +> **[libGDX](https://github.com/libgdx/libgdx)** β˜… 25.3k Apache-2.0 🟒
All-round cross-platform, high-level framework. + +> **[Litiengine](https://github.com/gurkenlabs/litiengine)** β˜… 834 MIT 🟒
AWT-based, lightweight 2D game engine. + +> **[LWJGL](https://github.com/LWJGL/lwjgl3)** β˜… 5.4k BSD-3-Clause 🟒
Robust framework that abstracts libraries like OpenGL/CL/AL. + +> **[Pathetic](https://github.com/bsommerfeld/pathetic)** β˜… 382 MIT 🟒
A highly configurable 3D A\* pathfinding library that uses specific optimizations for high performance. + +> **[vulkan4j](https://github.com/chuigda/vulkan4j)** β˜… 96 BSD-3-Clause πŸ”΄
Vulkan, OpenGL ES2 and GLFW Memory Allocator bindings. + +
+ +
+Geospatial 12 projects + +_Libraries for working with geospatial data and algorithms._ + +> **[Apache SIS](https://github.com/apache/sis)** β˜… 124 Apache-2.0 🟒
Library for developing geospatial applications. + +> **[ArcGIS Maps SDK for Java](https://github.com/Esri/arcgis-maps-sdk-java-samples/)** β˜… 131 Apache-2.0 🟠
JavaFX library for adding mapping and GIS functionality to desktop apps. + +> **[Geo](https://github.com/davidmoten/geo)** β˜… 434 Apache-2.0 🟒
GeoHash utilities in Java. + +> **[GeoTools](https://github.com/geotools/geotools)** β˜… 1.9k LGPL-2.1 🟒
Library that provides tools for geospatial data. + +> **[GraphHopper](https://github.com/graphhopper/graphhopper)** β˜… 6.6k Apache-2.0 🟒
Road-routing engine. Used as a Java library or standalone web service. + +> **[H2GIS](https://github.com/orbisgis/h2gis)** β˜… 220 LGPL-3.0 🟒
Spatial extension of the H2 database. + +> **[IP2Location.io Java SDK](https://github.com/ip2location/ip2location-io-java)** β˜… 10 MIT 🟠
Wrapper for the IP2Location.io Geolocation API and the IP2WHOIS domain WHOIS API. + +> **[Jgeohash](https://github.com/astrapi69/jgeohash)** β˜… 68 Apache-2.0 πŸ”΄
Library for using the GeoHash algorithm. + +> **[JTS](https://github.com/locationtech/jts)** β˜… 2.2k 🟒
Geometry model and algorithms for manipulating vector geospatial data. + +> **[Mapsforge](https://github.com/mapsforge/mapsforge)** β˜… 1.4k LGPL-3.0 🟒
Map rendering based on OpenStreetMap data. + +> **[Open Location Code](https://github.com/google/open-location-code)** β˜… 4.3k Apache-2.0 🟠
Encodes geographic coordinates as short, shareable Plus Codes. + +> **[Spatial4j](https://github.com/locationtech/spatial4j)** β˜… 962 🟒
General-purpose spatial/geospatial library. + +
+ +
+GUI 7 projects + +_Libraries to create modern graphical user interfaces._ + +> **[ControlsFX](https://github.com/controlsfx/controlsfx)** β˜… 1.7k BSD-3-Clause 🟒
UI controls and components that complement JavaFX. + +> **[FlatLaf](https://github.com/JFormDesigner/FlatLaf)** β˜… 4.2k Apache-2.0 🟒
Modern Swing Look and Feel with Darcula and IntelliJ themes. + +> **[JavaFX](https://github.com/openjdk/jfx)** β˜… 3.3k GPL-2.0 🟒
Successor of Swing. + +> **[Scene Builder](https://github.com/gluonhq/scenebuilder)** β˜… 819 🟠
Visual layout tool for JavaFX applications. + +> **[Sierra](https://github.com/HTTP-RPC/Sierra)** β˜… 150 Apache-2.0 🟒
Lightwieght declarative DSL for rapid development of Swing applications. + +> **[SnapKit](https://github.com/reportmill/SnapKit)** β˜… 331 🟒
Modern Java UI library for both desktop and web. + +> **[SWT](https://github.com/eclipse-platform/eclipse.platform.swt)** β˜… 200 EPL-2.0 🟒
Graphical widget toolkit. + +
+ +
+High Performance 8 projects + +_Everything about high-performance computation, from collections to specific libraries._ + +> **[Agrona](https://github.com/aeron-io/agrona)** β˜… 3.2k Apache-2.0 🟒
Data structures and utility methods that are common in high-performance applications. + +> **[Disruptor](https://github.com/LMAX-Exchange/disruptor)** β˜… 18.4k Apache-2.0 πŸ”΄
Inter-thread messaging library. + +> **[Eclipse Collections](https://github.com/eclipse-collections/eclipse-collections)** β˜… 2.6k 🟒
Collections framework inspired by Smalltalk. + +> **[fastutil](https://github.com/vigna/fastutil)** β˜… 2.2k Apache-2.0 🟒
Fast and compact type-specific collections. + +> **[Hollow](https://github.com/Netflix/hollow)** β˜… 1.4k Apache-2.0 🟒
High-performance in-memory datasets distributed from a single producer to many consumers. + +> **[HPPC](https://github.com/carrotsearch/hppc)** β˜… 1.0k Apache-2.0 🟒
Primitive collections. + +> **[JCTools](https://github.com/JCTools/JCTools)** β˜… 3.9k Apache-2.0 🟒
Concurrency tools currently missing from the JDK. + +> **[TransmittableThreadLocal](https://github.com/alibaba/transmittable-thread-local)** β˜… 8.3k Apache-2.0 🟒
Propagates thread-local context across thread pools and asynchronous execution. + +
+ +
+HTTP Clients 11 projects + +_Libraries that assist with creating HTTP requests and/or binding responses._ + +> **[Apache HttpComponents](https://hc.apache.org/)** β˜… 2.0k 🟒
Toolset of low-level Java components focused on HTTP and related protocols. + +> **[Async Http Client](https://github.com/AsyncHttpClient/async-http-client)** β˜… 6.4k Apache-2.0 🟒
Asynchronous HTTP and WebSocket client library. + +> **[Feign](https://github.com/OpenFeign/feign)** β˜… 9.8k Apache-2.0 🟒
HTTP client binder inspired by Retrofit, JAXRS-2.0, and WebSocket. + +> **[Google HTTP Client](https://github.com/googleapis/google-http-java-client)** β˜… 1.4k Apache-2.0 🟒
Pluggable HTTP transport abstraction with support for java.net.HttpURLConnection, Apache HTTP Client, Android, Google App Engine, XML, Gson, Jackson and Protobuf. + +> **[JQuickCurl](https://github.com/paohaijiao-jquick/jquick-curl)** β˜… 1.1k 🟒
Executes HTTP requests from cURL syntax through annotations, XML configuration and dynamic proxy clients. + +> **[methanol](https://github.com/mizosoft/methanol)** β˜… 297 MIT 🟠
HTTP client extensions library. + +> **[OkHttp](https://github.com/lysine-dev/okhttp)** β˜… 47.0k Apache-2.0 🟒
HTTP client for the JVM, Android and GraalVM. + +> **[Retrofit](https://github.com/lysine-dev/retrofit)** β˜… 43.9k Apache-2.0 🟒
Typesafe REST client. + +> **[Ribbon](https://github.com/Netflix/ribbon)** β˜… 4.6k Apache-2.0 🟠
Client-side IPC library that is battle-tested in the cloud. + +> **[Riptide](https://github.com/zalando/riptide)** β˜… 340 MIT 🟒
Client-side response routing for Spring's RestTemplate. + +> **[unirest-java](https://github.com/Kong/unirest-java)** β˜… 2.7k MIT 🟒
Simplified, lightweight HTTP client library. + +
+ +
+IDE 7 projects + +_Integrated development environments that try to simplify several aspects of development._ + +> **[Eclipse Java IDE](https://www.eclipse.org)** β˜… 644 EPL-2.0 🟒
Extensible Java IDE assembled from the Eclipse Platform, JDT and PDE. + +> **[Explyt](https://github.com/explyt/explyt)** β˜… 22 🟒
AI coding agent for JetBrains IDEs that uses IDE indexes, refactorings, test runners, static analysis and debugging for Java and Kotlin projects. + +> **[IntelliJ IDEA](https://github.com/JetBrains/intellij-community)** β˜… 20.4k 🟒
Supports many JVM languages and provides good options for Android development. The commercial edition targets the enterprise sector. + +> **[jGRASP](https://www.jgrasp.org)**
Created to provide software visualizations that work in conjunction with the debugger such as Control Structure Diagrams, UML class diagrams and Object Viewer. + +> **[NetBeans](https://github.com/apache/netbeans)** β˜… 3.1k Apache-2.0 🟒
Provides integration for several Java SE and EE features, from database access to HTML5. + +> **[SnapCode](https://github.com/reportmill/SnapCode)** β˜… 43 🟒
Modern IDE for Java running in the browser, focused on education. + +> **[Visual Studio Code Java](https://code.visualstudio.com/docs/languages/java)** β˜… 3.8k 🟒
Extension suite providing Java language support, debugging, testing, Maven, Gradle and project management in Visual Studio Code. + +
+ +
+Imagery 11 projects + +_Libraries that assist with the creation, evaluation or manipulation of graphical images._ + +> **[Barcode-Lib4J](https://github.com/vws-java/Barcode-Lib4J)** β˜… 18 Apache-2.0 🟒
Generates QR Code, DataMatrix, and other 1D/2D barcodes as vector (PDF, EPS, SVG) and raster (PNG, BMP, JPG) images with DPI awareness, high precision, and CMYK color model support. + +> **[Glide](https://github.com/bumptech/glide)** β˜… 35.0k 🟒
Image loading and caching library for Android focused on smooth scrolling. + +> **[image-comparison](https://github.com/romankh3/image-comparison)** β˜… 396 Apache-2.0 🟒
Library that compares 2 images with the same sizes and shows the differences visually by drawing rectangles. Some parts of the image can be excluded from the comparison. + +> **[Imgscalr](https://github.com/rkalla/imgscalr)** β˜… 1.2k Apache-2.0 πŸ”΄
Simple, efficient and hardware-accelerated image-scaling library implemented in pure Java 2D. + +> **[scrimage](https://github.com/sksamuel/scrimage)** β˜… 1.2k Apache-2.0 🟒
Immutable, functional, and performant JVM library for manipulation of images. + +> **[Tess4J](https://github.com/nguyenq/tess4j)** β˜… 1.8k Apache-2.0 🟒
JNA wrapper for Tesseract OCR API. + +> **[Thumbnailator](https://github.com/coobird/thumbnailator)** β˜… 5.4k MIT 🟠
High-quality thumbnail generation library. + +> **[TwelveMonkeys](https://github.com/haraldk/TwelveMonkeys)** β˜… 2.1k BSD-3-Clause 🟒
Collection of plugins that extend the number of supported image file formats. + +> **[vips-ffm](https://github.com/lopcode/vips-ffm)** β˜… 131 Apache-2.0 🟒
Comprehensive bindings for libvips, using Java's "Foreign Function & Memory" API. + +> **[webcam-capture](https://github.com/sarxos/webcam-capture)** β˜… 2.4k MIT 🟠
Library for using built-in and external webcams directly in Java. + +> **[ZXing](https://github.com/zxing/zxing)** β˜… 34.1k Apache-2.0 🟒
Multi-format 1D/2D barcode image processing library. + +
+ +
+Introspection 5 projects + +_Libraries that help make the Java introspection and reflection API easier and faster to use._ + +> **[ClassGraph](https://github.com/classgraph/classgraph)** β˜… 3.0k MIT 🟒
ClassGraph (formerly FastClasspathScanner) is an uber-fast, ultra-lightweight, parallelized classpath scanner and module scanner for Java, Scala, Kotlin and other JVM languages. + +> **[jOOR](https://github.com/jOOQ/jOOR)** β˜… 2.8k Apache-2.0 πŸ”΄
jOOR stands for jOOR Object Oriented Reflection. It is a simple wrapper for the java.lang.reflect package. + +> **[Objenesis](https://github.com/easymock/objenesis)** β˜… 631 Apache-2.0 🟒
Allows dynamic instantiation without default constructor, e.g. constructors which have required arguments, side effects or throw exceptions. + +> **[ReflectASM](https://github.com/EsotericSoftware/reflectasm)** β˜… 1.5k BSD-3-Clause πŸ”΄
ReflectASM is a very small Java library that provides high performance reflection by using code generation. + +> **[TypeTools](https://github.com/jhalterman/typetools)** β˜… 628 Apache-2.0 πŸ”΄
Tools for resolving generic types. + +
+ +
+Job Scheduling 7 projects + +_Libraries for scheduling background jobs._ + +> **[db-scheduler](https://github.com/kagkarlsson/db-scheduler)** β˜… 1.6k Apache-2.0 🟒
Persistent and cluster-friendly scheduler. + +> **[JobRunr](https://github.com/jobrunr/jobrunr)** β˜… 3.0k 🟒
Job scheduling library which utilizes lambdas for fire-and-forget, delayed and recurring jobs. Guarantees execution by single scheduler instance using optimistic locking. Has features for persistence, minimal dependencies and is embeddable. + +> **[Quartz](https://github.com/quartz-scheduler/quartz)** β˜… 6.7k Apache-2.0 🟒
Feature-rich, open source job scheduling library that can be integrated within virtually any Java application. + +> **[shedlock](https://github.com/lukas-krecan/ShedLock)** β˜… 4.2k Apache-2.0 🟒
Makes sure that your scheduled tasks are executed at most once at the same time. If a task is being executed on one node, it acquires a lock which prevents execution of the same task from another node or thread. + +> **[Sundial](https://github.com/knowm/Sundial)** β˜… 280 Apache-2.0 🟒
Lightweight framework to simply define jobs, define triggers and start the scheduler. + +> **[Wisp](https://github.com/Coreoz/Wisp)** β˜… 148 Apache-2.0 🟠
Simple library with minimal footprint and straightforward API. + +> **[XXL-JOB](https://github.com/xuxueli/xxl-job)** β˜… 30.4k GPL-3.0 🟒
Distributed task scheduling platform with centralized administration and execution monitoring. + +
+ +
+JSON 12 projects + +_Libraries for serializing and deserializing JSON to and from Java objects._ + +> **[Avaje Jsonb](https://github.com/avaje/avaje-jsonb)** β˜… 93 Apache-2.0 🟒
Reflection-free Json binding via source code generation with Jackson-like annotations. + +> **[DSL-JSON](https://github.com/ngs-doo/dsl-json)** β˜… 1.1k BSD-3-Clause 🟒
JSON library with advanced compile time databinding. + +> **[Fastjson2](https://github.com/alibaba/fastjson2)** β˜… 4.4k Apache-2.0 🟒
High-performance JSON parser, serializer and object mapper. + +> **[Gson](https://github.com/google/gson)** β˜… 24.2k Apache-2.0 🟒
Serializes objects to JSON and vice versa. Good performance with on-the-fly usage. + +> **[Jackson](https://github.com/FasterXML/jackson)** β˜… 9.8k 🟒
Similar to GSON, but offers performance gains if you need to instantiate the library more often. + +> **[jackson-modules-java8](https://github.com/FasterXML/jackson-modules-java8)** β˜… 423 Apache-2.0 🟒
Set of Jackson modules for Java 8 datatypes and features. + +> **[Jolt](https://github.com/bazaarvoice/jolt)** β˜… 1.7k Apache-2.0 🟒
JSON to JSON transformation tool. + +> **[JSON-io](https://github.com/jdereg/json-io)** β˜… 389 Apache-2.0 🟒
Convert Java to JSON/TOON and back. Supports complex object graphs, cyclic references, and TOON format for 40-50% LLM token savings. + +> **[JsonPath](https://github.com/json-path/JsonPath)** β˜… 9.4k Apache-2.0 🟠
Extract data from JSON using XPATH-like syntax. + +> **[JsonSurfer](https://github.com/jsurfer/JsonSurfer)** β˜… 316 MIT πŸ”΄
Streaming JsonPath processor dedicated to processing big and complicated JSON data. + +> **[Moshi](https://github.com/square/moshi)** β˜… 10.1k Apache-2.0 🟒
Modern JSON library, less opinionated and uses built-in types like List and Map. + +> **[Yasson](https://github.com/eclipse-ee4j/yasson)** β˜… 217 🟒
Binding layer between classes and JSON documents similar to JAXB. + +
+ +
+JVM and JDK 11 projects + +_Current implementations of the JVM/JDK._ + +> **[Corretto](https://aws.amazon.com/corretto/)**
No-cost, multiplatform, production-ready distribution of OpenJDK by Amazon. (GPL-2.0-only WITH Classpath-exception-2.0) + +> **[Dragonwell8](https://github.com/alibaba/dragonwell8)** β˜… 4.3k GPL-2.0 🟒
Downstream version of OpenJDK optimized for online e-commerce, financial, logistics applications. + +> **[Eclipse Temurin](https://github.com/adoptium/temurin-build)** β˜… 1.2k Apache-2.0 🟒
OpenJDK distribution from the Eclipse Adoptium project. + +> **[Graal](https://github.com/oracle/graal)** β˜… 21.7k 🟒
Polyglot embeddable JVM. (GPL-2.0-only WITH Classpath-exception-2.0) + +> **[Liberica JDK](https://bell-sw.com)**
Built from OpenJDK, thoroughly tested and passed the JCK. (GPL-2.0-only WITH Classpath-exception-2.0) + +> **[Microsoft JDK](https://github.com/microsoft/openjdk)** β˜… 342 MIT 🟠
Microsoft Build of OpenJDK, Free, Open Source, Freshly Brewed! + +> **[Open JDK](https://github.com/openjdk/jdk)** β˜… 23.2k GPL-2.0 🟒
Open JDK community home. + +> **[OpenJ9](https://github.com/eclipse-openj9/openj9)** β˜… 3.5k 🟒
High performance, enterprise-calibre, flexibly licensed, openly-governed cross-platform JVM extending and augmenting the runtime technology components from the Eclipse OMR and OpenJDK project. + +> **[RedHat Open JDK](https://developers.redhat.com/products/openjdk/overview)**
RedHat's OpenJDK distribution. (GPL-2.0-only WITH Classpath-exception-2.0) + +> **[SAP Machine](https://github.com/SAP/SapMachine)** β˜… 616 GPL-2.0 🟒
SAP's no-cost, rigorously tested and JCK-verified OpenJDK friendly fork. + +> **[Zulu](https://www.azul.com/products/zulu-community/)**
OpenJDK builds for Windows, Linux, and macOS. (GPL-2.0-only WITH Classpath-exception-2.0) + +
+ +
+Logging 10 projects + +_Libraries that log the behavior of an application._ + +> **[Apache Log4j 2](https://github.com/apache/logging-log4j2)** β˜… 3.6k Apache-2.0 🟒
Complete rewrite with a powerful plugin and configuration architecture. + +> **[Echopraxia](https://github.com/tersesystems/echopraxia)** β˜… 59 πŸ”΄
API designed around structured logging, rich context, and conditional logging. There are Logback and Log4J2 implementations, but Echopraxia's API is completely dependency-free, meaning it can be implemented with any logging API. + +> **[Flogger](https://github.com/google/flogger)** β˜… 1.5k Apache-2.0 🟒
Flogger is a fluent logging API for Java. It supports a wide variety of features, and has many benefits over existing logging APIs. + +> **[Graylog](https://github.com/Graylog2/graylog2-server)** β˜… 8.1k 🟒
Open-source aggregator suited for extended role and permission management. (GPL-3.0-only) + +> **[Kibana](https://github.com/elastic/kibana)** β˜… 21.2k 🟒
Analyzes and visualizes log files. Some features require payment. + +> **[Logback](https://github.com/qos-ch/logback)** β˜… 3.2k 🟒
Robust logging library with interesting configuration options via Groovy. + +> **[Logbook](https://github.com/zalando/logbook)** β˜… 2.1k MIT 🟒
Extensible, open-source library for HTTP request and response logging. + +> **[Logstash](https://github.com/elastic/logstash)** β˜… 14.9k 🟒
Tool for managing log files. + +> **[SLF4J](https://github.com/qos-ch/slf4j)** β˜… 2.5k MIT 🟒
Abstraction layer/simple logging facade. + +> **[tinylog](https://github.com/tinylog-org/tinylog)** β˜… 771 Apache-2.0 🟒
Lightweight logging framework with static logger class. + +
+ +
+Machine Learning 14 projects + +_Tools that provide specific statistical algorithms for learning from data._ + +> **[Apache Mahout](https://github.com/apache/mahout)** β˜… 2.3k Apache-2.0 🟒
Scalable algorithms focused on collaborative filtering, clustering and classification. + +> **[DatumBox](https://github.com/datumbox/datumbox-framework)** β˜… 1.1k Apache-2.0 πŸ”΄
Provides several algorithms and pre-trained models for natural language processing. + +> **[Deeplearning4j](https://github.com/deeplearning4j/deeplearning4j)** β˜… 14.2k Apache-2.0 🟒
Distributed and multi-threaded deep learning library. + +> **[DJL](https://github.com/deepjavalibrary/djl)** β˜… 4.8k Apache-2.0 🟒
High-level and engine-agnostic framework for deep learning. + +> **[H2O](https://github.com/h2oai/h2o-3)** β˜… 7.5k Apache-2.0 🟒
Analytics engine for statistics over big data. + +> **[Intelligent java](https://github.com/Barqawiz/IntelliJava)** β˜… 64 Apache-2.0 πŸ”΄
Seamlessly integrate with remote deep learning and language models programmatically. + +> **[JSAT](https://github.com/EdwardRaff/JSAT)** β˜… 794 GPL-3.0 πŸ”΄
Algorithms for pre-processing, classification, regression, and clustering with support for multi-threaded execution. + +> **[LIBSVM](https://github.com/cjlin1/libsvm)** β˜… 4.7k BSD-3-Clause 🟠
Support vector machine library with Java bindings and command-line tools. + +> **[Neureka](https://github.com/Gleethos/neureka)** β˜… 91 MIT 🟠
A lightweight, platform independent, OpenCL accelerated nd-array/tensor library. + +> **[oj! Algorithms](https://github.com/optimatika/ojAlgo)** β˜… 501 MIT 🟒
High-performance mathematics, linear algebra and optimisation needed for data science, machine learning and scientific computing. + +> **[sklearn-java](https://github.com/kVeyra/sklearn-java)** β˜… 3 Apache-2.0 🟒
Implements scikit-learn-style machine learning algorithms in pure Java. + +> **[Smile](https://github.com/haifengl/smile)** β˜… 6.4k 🟒
Statistical Machine Intelligence and Learning Engine provides a set of machine learning algorithms and a visualization library. + +> **[Tribuo](https://github.com/oracle/tribuo)** β˜… 1.4k Apache-2.0 🟒
Provides tools for classification, regression, clustering, model development and interfaces with other libraries such as scikit-learn, pytorch and TensorFlow. + +> **[Weka](https://git.cms.waikato.ac.nz/weka/weka)**
Collection of algorithms for data mining tasks ranging from pre-processing to visualization. + +
+ +
+Messaging 19 projects + +_Tools that help send messages between clients to ensure protocol independency._ + +> **[Aeron](https://github.com/aeron-io/aeron)** β˜… 8.8k Apache-2.0 🟒
Efficient, reliable, unicast and multicast message transport. + +> **[Apache ActiveMQ](https://github.com/apache/activemq)** β˜… 2.4k Apache-2.0 🟒
Message broker that implements JMS and converts synchronous to asynchronous communication. + +> **[Apache Camel](https://github.com/apache/camel)** β˜… 6.3k Apache-2.0 🟒
Glues together different transport APIs via Enterprise Integration Patterns. + +> **[Apache Kafka](https://github.com/apache/kafka)** β˜… 33.4k Apache-2.0 🟒
High-throughput distributed messaging system. + +> **[Apache Pulsar](https://github.com/apache/pulsar)** β˜… 15.3k Apache-2.0 🟒
Distributed pub/sub-messaging system. + +> **[Apache Qpid for Java](https://qpid.apache.org)** β˜… 212 Apache-2.0 🟒
Java messaging clients and brokers implementing AMQP. + +> **[Apache RocketMQ](https://github.com/apache/rocketmq)** β˜… 22.5k Apache-2.0 🟒
Fast, reliable, and scalable distributed messaging platform. + +> **[AutoMQ](https://github.com/AutoMQ/automq)** β˜… 10.4k Apache-2.0 🟒
AutoMQ is a cloud-native, serverless reinvented Kafka that is easily scalable, manage-less and cost-effective. + +> **[CloudEvents Java SDK](https://github.com/cloudevents/sdk-java)** β˜… 442 Apache-2.0 🟒
Java SDK for creating, serializing and transporting CloudEvents. + +> **[Emissary](https://github.com/joel-jeremy/emissary)** β˜… 109 Apache-2.0 🟠
Simple, lightweight, yet FAST messaging library for decoupling messages (requests and events) and message handlers. + +> **[Hermes](https://github.com/allegro/hermes)** β˜… 862 🟒
Fast and reliable message broker built on top of Kafka. + +> **[HiveMQ MQTT Client](https://github.com/hivemq/hivemq-mqtt-client)** β˜… 1.1k Apache-2.0 🟒
Reactive and blocking Java client for MQTT 3.1.1 and MQTT 5. + +> **[JeroMQ](https://github.com/zeromq/jeromq)** β˜… 2.4k MPL-2.0 🟠
Implementation of ZeroMQ. + +> **[NATS client](https://github.com/nats-io/nats.java)** β˜… 671 Apache-2.0 🟒
NATS client. + +> **[Pushy](https://github.com/jchambers/pushy)** β˜… 1.9k MIT 🟒
Java library for sending Apple Push Notification service messages. + +> **[RabbitMQ Java client](https://github.com/rabbitmq/rabbitmq-java-client)** β˜… 1.3k 🟒
RabbitMQ client. + +> **[Simple Java Mail](https://github.com/bbottema/simple-java-mail)** β˜… 1.3k Apache-2.0 🟒
Mailing with a clean and fluent API. + +> **[Smack](https://github.com/igniterealtime/Smack)** β˜… 2.4k Apache-2.0 🟒
Cross-platform XMPP client library. + +> **[Svix](https://github.com/svix/svix-webhooks/tree/main/java)** β˜… 3.3k MIT 🟒
Library for the Svix API to send webhooks and verify signatures. + +
+ +
+Microservice 8 projects + +_Tools for creating and managing microservices._ + +> **[Armeria](https://github.com/line/armeria)** β˜… 5.1k Apache-2.0 🟒
Asynchronous RPC/REST client/server library built on top of Java 8, Netty, HTTP/2, Thrift and gRPC. + +> **[Eureka](https://github.com/Netflix/eureka)** β˜… 12.7k Apache-2.0 🟠
REST-based service registry for resilient load balancing and failover. + +> **[gRPC Spring](https://github.com/grpc-ecosystem/grpc-spring)** β˜… 3.7k Apache-2.0 🟒
Spring Boot integration for building gRPC clients and servers. + +> **[Helidon](https://github.com/helidon-io/helidon)** β˜… 3.8k Apache-2.0 🟒
Two-style approach for writing microservices: Functional-reactive and as an implementation of MicroProfile. + +> **[Micronaut](https://github.com/micronaut-projects/micronaut-core)** β˜… 6.4k Apache-2.0 🟒
Modern full-stack framework with focus on modularity, minimal memory footprint and startup time. + +> **[Nacos](https://github.com/alibaba/nacos)** β˜… 33.2k Apache-2.0 🟒
Dynamic service discovery, configuration and service management platform for building cloud native applications. + +> **[Quarkus](https://github.com/quarkusio/quarkus)** β˜… 15.8k Apache-2.0 🟒
Kubernetes stack tailored for the HotSpot and Graal VM. + +> **[Sentinel](https://github.com/alibaba/Sentinel)** β˜… 23.1k Apache-2.0 🟒
Flow control component enabling reliability, resilience and monitoring for microservices. + +
+ +
+Miscellaneous 3 projects + +_Everything else._ + +> **[JBake](https://github.com/jbake-org/jbake)** β˜… 1.2k MIT 🟠
Static website generator. + +> **[JObfuscator](https://www.pelock.com/products/jobfuscator)**
Source code obfuscator. + +> **[yGuard](https://github.com/yWorks/yGuard)** β˜… 479 MIT 🟠
Obfuscation via renaming and shrinking. + +
+ +
+Mobile Development 4 projects + +_Tools for creating or managing mobile applications._ + +> **[Codename One](https://github.com/codenameone/CodenameOne)** β˜… 1.9k 🟒
Cross-platform solution for writing native mobile apps. (GPL-2.0-only WITH Classpath-exception-2.0) + +> **[Gluon Substrate](https://github.com/gluonhq/substrate)** β˜… 443 GPL-2.0 🟒
Builds native JavaFX applications for desktop, mobile and embedded targets. + +> **[MobileUI](https://github.com/MobileUI/mobileui)** β˜… 13 MIT πŸ”΄
Cross-platform framework for developing mobile apps with native UI in Java and Kotlin. + +> **[Multi-OS Engine](https://github.com/multi-os-engine/multi-os-engine)** β˜… 596 Apache-2.0 🟒
Open-source, cross-platform engine to develop native mobile (iOS, Android, etc.) apps. + +
+ +
+Monitoring 21 projects + +_Tools that observe/monitor applications in production by providing telemetry._ + +> **[Apitally](https://github.com/apitally/apitally-java)** β˜… 6 MIT 🟒
Simple, privacy-focused API monitoring, analytics and request logging for Spring Boot apps. + +> **[Arthas](https://github.com/alibaba/arthas)** β˜… 37.5k Apache-2.0 🟒
Allows to troubleshoot production issues for applications without modifying code or restarting servers. + +> **[Automon](https://github.com/stevensouza/automon)** β˜… 571 Apache-2.0 πŸ”΄
Combines the power of AOP with monitoring and/or logging tools. + +> **[Boot Usage Spring Boot Starter](https://github.com/dhruv-15-03/boot-usage)** β˜… 2 Apache-2.0 🟒
Spring Boot Actuator extension providing application startup and runtime metrics including JVM uptime, memory usage, and CPU load. + +> **[BTrace](https://github.com/btraceio/btrace)** β˜… 6.0k Apache-2.0 🟒
Dynamic tracing and diagnostics for running JVM applications without restarts. + +> **[Datadog](https://github.com/DataDog/dd-trace-java)** β˜… 727 Apache-2.0 🟒
Modern monitoring & analytics. + +> **[Dropwizard Metrics](https://github.com/dropwizard/metrics)** β˜… 7.8k Apache-2.0 🟒
Expose metrics via JMX or HTTP and send them to a database. + +> **[Glowroot](https://github.com/glowroot/glowroot)** β˜… 1.4k Apache-2.0 🟒
Open-source Java APM. + +> **[HertzBeat](https://github.com/dromara/hertzbeat)** β˜… 7.3k Apache-2.0 🟒
Real-time monitoring system with custom-monitor and agentless. + +> **[hippo4j](https://github.com/opengoofy/hippo4j/blob/develop/README-EN.md)** β˜… 6.0k Apache-2.0 🟠
Dynamic and observable thread pool framework. + +> **[inspectIT Ocelot](https://github.com/inspectIT/inspectit-ocelot)** β˜… 220 Apache-2.0 🟠
Java agent that collects application performance, tracing and behavioral data. + +> **[JavaMelody](https://github.com/javamelody/javamelody)** β˜… 3.0k Apache-2.0 🟒
Performance monitoring and profiling. + +> **[Jolokia](https://github.com/jolokia/jolokia)** β˜… 849 Apache-2.0 🟒
JMX over REST. + +> **[Micrometer](https://github.com/micrometer-metrics/micrometer)** β˜… 4.9k Apache-2.0 🟒
Vendor-neutral metrics/observability facade for the most popular metrics/observability libraries. + +> **[Micrometer Tracing](https://github.com/micrometer-metrics/tracing)** β˜… 296 Apache-2.0 🟒
Vendor-neutral distributed tracing facade for the most popular tracer libraries. + +> **[OpenTelemetry](https://github.com/open-telemetry/opentelemetry-java)** β˜… 2.4k Apache-2.0 🟒
Instrument, generate, collect, and export telemetry data to help you analyze your software’s performance and behavior. + +> **[Pinpoint](https://github.com/naver/pinpoint)** β˜… 13.8k Apache-2.0 🟒
Open-source APM tool. + +> **[Prometheus](https://github.com/prometheus/client_java)** β˜… 2.3k Apache-2.0 🟒
Provides a multi-dimensional data model, DSL, autonomous server nodes and much more. + +> **[Sentry](https://github.com/getsentry/sentry-java)** β˜… 1.3k MIT 🟒
Integration with [Sentry](https://github.com/getsentry/sentry), an application error tracking and performance analysis platform. + +> **[SPM](https://github.com/sematext/sematext-agent-java)** β˜… 25 Apache-2.0 🟒
Performance monitor with distributing transaction tracing for JVM apps. + +> **[zipkin](https://github.com/openzipkin/zipkin)** β˜… 17.5k Apache-2.0 🟠
Distributed tracing system which gathers timing data needed to troubleshoot latency problems in microservice architectures. + +
+ +
+Native 6 projects + +_For working with platform-specific native libraries._ + +> **[Aparapi](https://git.cleverlibre.org/aparapi/aparapi)**
Converts bytecode to OpenCL which allows execution on GPUs. + +> **[JavaCPP](https://github.com/bytedeco/javacpp)** β˜… 4.7k 🟒
Provides efficient and easy access to native C++. + +> **[JCuda](https://github.com/jcuda/jcuda)** β˜… 266 MIT πŸ”΄
JCuda offers Java bindings for CUDA and CUDA-related libraries. + +> **[JNA](https://github.com/java-native-access/jna)** β˜… 8.9k 🟒
Work with native libraries without writing JNI. Also provides interfaces to common system libraries. + +> **[JNR](https://github.com/jnr/jnr-ffi)** β˜… 1.3k 🟒
Work with native libraries without writing JNI. Also provides interfaces to common system libraries. Same goals as JNA, but faster, and serves as the basis for the upcoming [Project Panama](https://openjdk.java.net/projects/panama). + +> **[native-lib-loader](https://github.com/scijava/native-lib-loader)** β˜… 220 πŸ”΄
Native library loader for extracting and loading native libraries from Java. + +
+ +
+Natural Language Processing 5 projects + +_Libraries that specialize in processing text._ + +> **[Apache OpenNLP](https://github.com/apache/opennlp)** β˜… 1.6k Apache-2.0 🟒
Toolkit for machine-learning-based natural language processing. + +> **[CoreNLP](https://github.com/stanfordnlp/CoreNLP)** β˜… 10.1k GPL-3.0 🟒
Provides a set of fundamental tools for tasks like tagging, named entity recognition, and sentiment analysis. + +> **[DKPro](https://github.com/dkpro/dkpro-core)** β˜… 204 🟒
Collection of reusable NLP tools for linguistic pre-processing, machine learning, lexical resources, etc. + +> **[Hypherator](https://github.com/ejossev/hypherator-java)** β˜… 4 MIT πŸ”΄
Java hyphenation library with iterator-like interface. Can be used out-of-the box - dictionaries for multiple languages are bundled in. + +> **[LingPipe](https://alias-i.com/lingpipe/)**
Toolkit for tasks ranging from POS tagging to sentiment analysis. + +
+ +
+Networking 21 projects + +_Libraries for building network clients and servers._ + +> **[AISmessages](https://github.com/tbsalling/aismessages)** β˜… 168 🟒
Decodes NMEA-armoured AIS messages for maritime navigation and safety systems with ITU-R M.1371 support and no runtime dependencies. (CC-BY-NC-SA-4.0) + +> **[Apache MINA sshd](https://github.com/apache/mina-sshd)** β˜… 1.1k Apache-2.0 🟒
Java implementation of SSH clients, servers, SFTP and SCP. + +> **[Atmosphere](https://github.com/Atmosphere/atmosphere)** β˜… 3.8k Apache-2.0 🟒
Real-time transport framework supporting WebSocket, SSE, gRPC and WebTransport. + +> **[Commons-networking](https://github.com/CiscoSE/commons-networking)** β˜… 21 Apache-2.0 πŸ”΄
Client for server-sent events (SSE). + +> **[dnsjava](https://github.com/dnsjava/dnsjava)** β˜… 1.1k BSD-3-Clause 🟒
Java implementation of the DNS protocol. + +> **[Drift](https://github.com/airlift/drift)** β˜… 249 Apache-2.0 🟒
Easy-to-use, annotation-based library for creating Thrift clients and serializable types. + +> **[Dubbo](https://github.com/apache/dubbo)** β˜… 41.5k Apache-2.0 🟒
High-performance RPC framework. + +> **[Fluency](https://github.com/komamitsu/fluency)** β˜… 167 Apache-2.0 🟒
High throughput data ingestion logger to Fluentd and Fluent Bit. + +> **[Grizzly](https://github.com/eclipse-ee4j/grizzly)** β˜… 180 🟒
NIO framework. Used as a network layer in Glassfish. + +> **[gRPC-java](https://github.com/grpc/grpc-java)** β˜… 12.1k Apache-2.0 🟒
RPC framework based on protobuf and HTTP/2. + +> **[java-ngrok](https://github.com/alexdlaird/java-ngrok)** β˜… 60 MIT 🟒
Java wrapper for ngrok; programmatic tunnels for ingress, webhooks, demos, and APIs. + +> **[Java-WebSocket](https://github.com/TooTallNate/Java-WebSocket)** β˜… 10.8k MIT 🟠
Lightweight WebSocket client and server implementation. + +> **[MINA](https://github.com/apache/mina)** β˜… 925 Apache-2.0 🟒
Abstract, event-driven async I/O API for network operations over TCP/IP and UDP/IP via Java NIO. + +> **[MinimalFTP](https://github.com/Guichaguri/MinimalFTP)** β˜… 191 Apache-2.0 πŸ”΄
Lightweight, small and customizable FTP server. + +> **[Netty](https://github.com/netty/netty)** β˜… 35.0k Apache-2.0 🟒
Framework for building high-performance network applications. + +> **[ServiceTalk](https://github.com/apple/servicetalk)** β˜… 1.0k Apache-2.0 🟒
Framework built on Netty with APIs tailored to specific protocols and support for multiple programming paradigms. + +> **[Socket.IO Client Java](https://github.com/socketio/socket.io-client-java)** β˜… 5.4k 🟠
Java client for Socket.IO servers. + +> **[sshj](https://github.com/hierynomus/sshj)** β˜… 2.7k Apache-2.0 🟒
Programmatically use SSH, SCP or SFTP. + +> **[TLS Channel](https://github.com/marianobarrios/tls-channel)** β˜… 209 MIT 🟠
Implements a ByteChannel interface over SSLEngine, enabling easy-to-use (socket-like) TLS. + +> **[Undertow](https://github.com/undertow-io/undertow)** β˜… 3.8k Apache-2.0 🟒
Web server providing both blocking and non-blocking APIs based on NIO. Used as a network layer in WildFly. + +> **[urnlib](https://github.com/slub/urnlib)** β˜… 36 GPL-3.0 🟠
Represent, parse and encode URNs, as in RFC 2141. + +
+ +
+ORM 11 projects + +_APIs that handle the persistence of objects._ + +> **[Apache Cayenne](https://github.com/apache/cayenne)** β˜… 344 🟒
Provides a clean, static API for data access. Also includes a GUI Modeler for working with database mappings, and DB reverse engineering and generation. + +> **[Doma](https://github.com/domaframework/doma)** β˜… 504 Apache-2.0 🟒
Database access framework that verifies and generates source code at compile time using annotation processing as well as native SQL templates called two-way SQL. + +> **[Ebean](https://github.com/ebean-orm/ebean)** β˜… 1.5k Apache-2.0 🟒
Provides simple and fast data access. + +> **[EclipseLink](https://github.com/eclipse-ee4j/eclipselink)** β˜… 242 🟒
Supports a number of persistence standards: JPA, JAXB, JCA and SDO. + +> **[Hibernate](https://github.com/hibernate/hibernate-orm)** β˜… 6.5k Apache-2.0 🟒
Robust and widely used, with an active community. + +> **[MyBatis](https://github.com/mybatis/mybatis-3)** β˜… 20.4k Apache-2.0 🟒
Couples objects with stored procedures or SQL statements. + +> **[mybatis-dynamic](https://github.com/myacelw/mybatis-dynamic)** β˜… 4 🟠
Code-first dynamic ORM for MyBatis with runtime schema modification. + +> **[MyBatis-Plus](https://github.com/baomidou/mybatis-plus)** β˜… 17.4k Apache-2.0 🟒
A powerful enhanced toolkit of MyBatis for simplifying development. + +> **[ObjectiveSql](https://github.com/braisdom/ObjectiveSql)** β˜… 1.3k Apache-2.0 πŸ”΄
ActiveRecord ORM for rapid development and convention over configuration. + +> **[Permazen](https://github.com/permazen/permazen)** β˜… 423 Apache-2.0 🟠
Language-natural persistence layer. + +> **[SimpleFlatMapper](https://github.com/arnaudroger/SimpleFlatMapper)** β˜… 459 MIT 🟠
Simple database and CSV mapper. + +
+ +
+PaaS 6 projects + +_Java platform as a service._ + +> **[AWS Elastic Beanstalk](https://aws.amazon.com/elasticbeanstalk/)**
AWS-based, with support for Tomcat and Jetty. + +> **[AWS Lambda](https://aws.amazon.com/lambda/)**
Serverless computation. + +> **[Google Cloud](https://cloud.google.com)**
Google's cloud infrastructure. + +> **[Heroku](https://www.heroku.com)**
Abstract computing environments. + +> **[Microsoft Azure](https://azure.microsoft.com/en-us/)**
Microsoft's cloud infrastructure. + +> **[OpenShift](https://www.openshift.com)**
Provides additionally an on-premise solution. + +
+ +
+PDF 13 projects + +_Tools to help with PDF files._ + +> **[Apache FOP](https://github.com/apache/xmlgraphics-fop)** β˜… 225 Apache-2.0 🟒
Creates PDFs from XSL-FO. + +> **[Apache PDFBox](https://github.com/apache/pdfbox)** β˜… 3.1k Apache-2.0 🟒
Toolbox for creating and manipulating PDFs. + +> **[DynamicReports](https://github.com/dynamicreports/dynamicreports)** β˜… 244 LGPL-3.0 🟒
Simplifies JasperReports. + +> **[Eclipse BIRT](https://github.com/eclipse-birt/birt)** β˜… 540 EPL-2.0 🟒
Report engine for creating PDF and other formats (DOCX, XLSX, HTML, etc) using Eclipse-based visual editor. + +> **[flyingsaucer](https://github.com/flyingsaucerproject/flyingsaucer)** β˜… 2.2k 🟒
XML/XHTML and CSS 2.1 renderer. (LGPL-2.1-or-later) + +> **[GraphCompose](https://github.com/DemchaAV/GraphCompose)** β˜… 106 MIT 🟒
Declarative engine for structured business PDFs with semantic layout, atomic pagination, theme tokens, and native vector charts. + +> **[iText](https://github.com/itext/itext-java)** β˜… 2.3k 🟒
Creates PDF files programmatically. + +> **[JasperReports](https://github.com/Jaspersoft/jasperreports)** β˜… 1.4k LGPL-3.0 🟒
Complex reporting engine. + +> **[jquick-pdf](https://github.com/paohaijiao/jquick-pdf)** β˜… 225 🟒
Generates PDFs from HTML-like templates and ECharts-style charts using iText 7, without a browser dependency. + +> **[Nostrum Dynamic Jasper](https://github.com/nostrum-tech/NostrumDynamicJasper)** β˜… 1 LGPL-3.0 🟒
Provides dynamic report layouts on top of JasperReports. + +> **[Open HTML to PDF](https://github.com/openhtmltopdf/openhtmltopdf)** β˜… 267 🟒
Properly supports modern PDF standards based on flyingsaucer and Apache PDFBox. + +> **[OpenDataLoader PDF](https://github.com/opendataloader-project/opendataloader-pdf)** β˜… 28.1k Apache-2.0 🟒
Parses PDFs into structured Markdown, JSON and HTML through a Java API and command line. + +> **[OpenPDF](https://github.com/LibrePDF/OpenPDF)** β˜… 4.3k 🟒
Open-source iText fork. (LGPL-3.0-only & MPL-2.0) + +
+ +
+Performance analysis 11 projects + +_Tools for performance analysis, profiling and benchmarking._ + +> **[Argus](https://github.com/rlaope/Argus)** β˜… 17 MIT 🟒
JVM diagnostics CLI for jcmd, JFR, async-profiler, heap analysis and machine-readable health verdicts. + +> **[async-profiler](https://github.com/async-profiler/async-profiler)** β˜… 9.1k Apache-2.0 🟒
Low-overhead sampling profiler for CPU, allocation and lock analysis on the JVM. + +> **[fastThread](https://fastthread.io)**
Analyze and visualize thread dumps with a free cloud-based upload interface. + +> **[GCeasy](https://gceasy.io)**
Tool to analyze and visualize GC logs. It provides a free cloud-based upload interface. + +> **[Heap Seance](https://github.com/SegfaultSorcerer/heap-seance)** β˜… 4 Apache-2.0 🟠
Memory leak diagnostics that orchestrates jcmd, jmap, jstat, JFR, Eclipse MAT, and async-profiler into a structured investigation workflow with confidence-based verdicts. + +> **[JDK Mission Control](https://github.com/openjdk/jmc)** β˜… 983 🟒
Profiling and diagnostics suite for JVM applications using Java Flight Recorder. + +> **[jHiccup](https://github.com/giltene/jHiccup)** β˜… 704 🟠
Logs and records platform JVM stalls. + +> **[JITWatch](https://github.com/AdoptOpenJDK/jitwatch)** β˜… 3.3k 🟠
Analyze the JIT compiler optimisations made by the HotSpot JVM. + +> **[JMH](https://github.com/openjdk/jmh)** β˜… 2.7k GPL-2.0 🟒
Harness for building, running, and analysing nano/micro/milli/macro benchmarks written in Java and other languages targeting the JVM. + +> **[JVM Hotpath](https://github.com/sfkamath/jvm-hotpath)** β˜… 10 MIT 🟠
Java agent for line-level execution frequency analysis to identify algorithmic bottlenecks. + +> **[LatencyUtils](https://github.com/LatencyUtils/LatencyUtils)** β˜… 466 πŸ”΄
Utilities for latency measurement and reporting. + +
+ +
+Platform 52 projects + +_Frameworks that are suites of multiple libraries encompassing several categories._ + +#### Apache Commons 49 projects + +> **[BCEL](https://github.com/apache/commons-bcel)** β˜… 273 Apache-2.0 🟒
Byte Code Engineering Library - analyze, create, and manipulate Java class files. + +> **[BeanUtils](https://github.com/apache/commons-beanutils)** β˜… 322 Apache-2.0 🟒
Easy-to-use wrappers around the Java reflection and introspection APIs. + +> **[BSF](https://github.com/apache/commons-bsf)** β˜… 32 Apache-2.0 🟒
Bean Scripting Framework - interface to scripting languages, including JSR-223. + +> **[ClassScan](https://commons.apache.org/sandbox/commons-classscan/)**
Find Class interfaces, methods, fields, and annotations without loading. + +> **[CLI](https://github.com/apache/commons-cli)** β˜… 393 Apache-2.0 🟒
Command-line arguments parser. + +> **[CLI2](https://commons.apache.org/sandbox/commons-cli2/)**
Redesign of Commons CLI. + +> **[Codec](https://github.com/apache/commons-codec)** β˜… 490 Apache-2.0 🟒
General encoding/decoding algorithms, e.g. phonetic, base64 or URL. + +> **[Collections](https://github.com/apache/commons-collections)** β˜… 726 Apache-2.0 🟒
Extends or augments the Java Collections Framework. + +> **[Compress](https://github.com/apache/commons-compress)** β˜… 402 Apache-2.0 🟒
Defines an API for working with tar, zip and bzip2 files. + +> **[Configuration](https://github.com/apache/commons-configuration)** β˜… 215 Apache-2.0 🟒
Reading of configuration/preferences files in various formats. + +> **[Convert](https://commons.apache.org/sandbox/commons-convert/)**
Commons-Convert aims to provide a single library dedicated to the task of converting an object of one type to another. + +> **[CSV](https://github.com/apache/commons-csv)** β˜… 414 Apache-2.0 🟒
Component for reading and writing comma separated value files. + +> **[Daemon](https://github.com/apache/commons-daemon)** β˜… 107 Apache-2.0 🟒
Alternative invocation mechanism for unix-daemon-like java code. + +> **[DBCP](https://github.com/apache/commons-dbcp)** β˜… 368 Apache-2.0 🟒
Database connection pooling services. + +> **[DbUtils](https://github.com/apache/commons-dbutils)** β˜… 392 Apache-2.0 🟒
JDBC helper library. + +> **[Digester](https://github.com/apache/commons-digester)** β˜… 62 Apache-2.0 🟒
XML-to-Java-object mapping utility. + +> **[Email](https://github.com/apache/commons-email)** β˜… 177 Apache-2.0 🟒
Library for sending e-mail from Java. + +> **[Exec](https://github.com/apache/commons-exec)** β˜… 162 Apache-2.0 🟒
API for dealing with external process execution and environment management in Java. + +> **[FileUpload](https://github.com/apache/commons-fileupload)** β˜… 261 Apache-2.0 🟒
File upload capability for your servlets and web applications. + +> **[Finder](https://commons.apache.org/sandbox/commons-finder/)**
Java library inspired by the UNIX find command. + +> **[Flatfile](https://commons.apache.org/sandbox/commons-flatfile/)**
Java library for working with flat data structures. + +> **[Graph](https://github.com/apache/commons-graph)** β˜… 44 Apache-2.0 🟒
General purpose graph APIs and algorithms. + +> **[I18n](https://commons.apache.org/sandbox/commons-i18n/)**
Adds the feature of localized message bundles that consist of one or many localized texts that belong together. + +> **[Id](https://commons.apache.org/sandbox/commons-id/)**
Id is a component used to generate identifiers. + +> **[Imaging](https://github.com/apache/commons-imaging)** β˜… 487 Apache-2.0 🟒
Image library. + +> **[IO](https://github.com/apache/commons-io)** β˜… 1.1k Apache-2.0 🟒
Collection of I/O utilities. + +> **[Javaflow](https://commons.apache.org/sandbox/commons-javaflow/)**
Continuation implementation to capture the state of the application. + +> **[JCI](https://github.com/apache/commons-jci)** β˜… 22 Apache-2.0 🟒
Java Compiler Interface. + +> **[JCS](https://github.com/apache/commons-jcs)** β˜… 108 Apache-2.0 🟒
Java Caching System. + +> **[Jelly](https://github.com/apache/commons-jelly)** β˜… 26 Apache-2.0 🟒
XML based scripting and processing engine. + +> **[Jexl](https://github.com/apache/commons-jexl)** β˜… 242 Apache-2.0 🟒
Expression language which extends the Expression Language of the JSTL. + +> **[JNet](https://commons.apache.org/sandbox/commons-jnet/)**
JNet allows to use dynamically register url stream handlers through the java.net API. + +> **[JXPath](https://github.com/apache/commons-jxpath)** β˜… 43 Apache-2.0 🟒
Utilities for manipulating Java Beans using the XPath syntax. + +> **[Lang](https://github.com/apache/commons-lang)** β˜… 3.0k Apache-2.0 🟒
Provides extra functionality for classes in java.lang. + +> **[Logging](https://github.com/apache/commons-logging)** β˜… 168 Apache-2.0 🟒
Wrapper around a variety of logging API implementations. + +> **[Math](https://github.com/apache/commons-math)** β˜… 651 Apache-2.0 🟒
Lightweight, self-contained mathematics and statistics components. + +> **[Monitoring](https://commons.apache.org/sandbox/commons-monitoring/)**
Monitoring aims to provide a simple but extensible monitoring solution for Java applications. + +> **[Nabla](https://commons.apache.org/sandbox/commons-nabla/)**
Nabla provides automatic differentiation classes that can generate derivative of any function implemented in the Java language. + +> **[Net](https://github.com/apache/commons-net)** β˜… 296 Apache-2.0 🟒
Collection of network utilities and protocol implementations. + +> **[OpenPGP](https://commons.apache.org/sandbox/commons-openpgp/)**
Interface to signing and verifying data using OpenPGP. + +> **[Performance](https://commons.apache.org/sandbox/commons-performance/)**
Small framework for microbenchmark clients, with implementations for Commons DBCP and Pool. + +> **[Pipeline](https://commons.apache.org/sandbox/commons-pipeline/)**
Provides a set of pipeline utilities designed around work queues that run in parallel to sequentially process data objects. + +> **[Pool](https://github.com/apache/commons-pool)** β˜… 553 Apache-2.0 🟒
Generic object pooling component. + +> **[RDF](https://github.com/apache/commons-rdf)** β˜… 58 Apache-2.0 🟒
Common implementation of RDF 1.1 that could be implemented by systems on the JVM. + +> **[RNG](https://github.com/apache/commons-rng)** β˜… 66 Apache-2.0 🟒
Commons Rng provides implementations of pseudo-random numbers generators. + +> **[SCXML](https://github.com/apache/commons-scxml)** β˜… 67 Apache-2.0 🟒
Implementation of the State Chart XML specification aimed at creating and maintaining a Java SCXML engine. + +> **[Validator](https://github.com/apache/commons-validator)** β˜… 230 Apache-2.0 🟒
Framework to define validators and validation rules in an xml file. + +> **[VFS](https://github.com/apache/commons-vfs)** β˜… 251 Apache-2.0 🟒
Virtual File System component for treating files, FTP, SMB, ZIP and such like as a single logical file system. + +> **[Weaver](https://github.com/apache/commons-weaver)** β˜… 29 Apache-2.0 🟒
Provides an easy way to enhance (weave) compiled bytecode. + +#### Other 3 projects + +> **[CUBA Platform](https://github.com/jmix-framework/jmix)** β˜… 695 Apache-2.0 🟒
High-level framework for developing enterprise applications with a rich web interface, based on Spring, EclipseLink and Vaadin. + +> **[Light-4J](https://github.com/networknt/light-4j/)** β˜… 3.7k Apache-2.0 🟒
Fast, lightweight and productive microservices framework with built-in security. + +> **[Spring Framework](https://github.com/spring-projects/spring-framework)** β˜… 60.1k Apache-2.0 🟒
Comprehensive application framework for building Java applications. + +
+ +
+Processes 3 projects + +_Libraries that help the management of operating system processes._ + +> **[ch.vorburger.exec](https://github.com/vorburger/ch.vorburger.exec)** β˜… 41 Apache-2.0 🟒
Convenient API around Apache Commons Exec. + +> **[zt-exec](https://github.com/zeroturnaround/zt-exec)** β˜… 915 Apache-2.0 🟒
Provides a unified API to Apache Commons Exec and ProcessBuilder. + +> **[zt-process-killer](https://github.com/zeroturnaround/zt-process-killer)** β˜… 139 Apache-2.0 🟒
Stops processes started from Java or the system processes via PID. + +
+ +
+Proxy Servers 5 projects + +_Java proxy and gateway servers for routing and mediating traffic._ + +> **[LittleProxy](https://github.com/LittleProxy/LittleProxy)** β˜… 150 Apache-2.0 🟒
High performance HTTP proxy atop Netty's event-based networking library. + +> **[Membrane Service Proxy](https://github.com/membrane/api-gateway)** β˜… 628 Apache-2.0 🟒
Open-source, reverse-proxy framework. + +> **[OpenIG](https://github.com/OpenIdentityPlatform/OpenIG)** β˜… 90 🟒
High-performance reverse proxy server with specialized session management and credential replay functionality. + +> **[Spring Cloud Gateway](https://github.com/spring-cloud/spring-cloud-gateway)** β˜… 4.9k Apache-2.0 🟒
API gateway built on Spring Framework and Spring Boot. + +> **[Zuul](https://github.com/Netflix/zuul)** β˜… 14.1k Apache-2.0 🟒
Gateway service that provides dynamic routing, monitoring, resiliency, security, and more. + +
+ +
+Reactive libraries 5 projects + +_Libraries for developing reactive applications._ + +> **[Akka](https://github.com/akka/akka)** β˜… 13.3k 🟒
Toolkit and runtime for building concurrent, distributed, fault-tolerant and event-driven applications. + +> **[Reactive Streams](https://github.com/reactive-streams/reactive-streams-jvm)** β˜… 4.9k MIT-0 πŸ”΄
Provides a standard for asynchronous stream processing with non-blocking backpressure. + +> **[Reactor](https://github.com/reactor/reactor)** β˜… 3.7k Apache-2.0 🟒
A framework for building non-blocking applications on the JVM, providing support for reactive programming. + +> **[RxJava](https://github.com/ReactiveX/RxJava)** β˜… 48.2k Apache-2.0 🟒
Allows for composing asynchronous and event-based programs using observable sequences. + +> **[vert.x](https://github.com/eclipse-vertx/vert.x)** β˜… 14.7k 🟒
Polyglot event-driven application framework. + +
+ +
+Regular Expressions 4 projects + +_Libraries and engines for building and evaluating regular expressions._ + +> **[dregex](https://github.com/marianobarrios/dregex)** β˜… 55 BSD-2-Clause 🟠
Regular expression engine that uses deterministic finite automata. It supports some Perl-style features and yet retains linear matching time, and also offers set operations. + +> **[JavaVerbalExpressions](https://github.com/VerbalExpressions/JavaVerbalExpressions)** β˜… 2.6k MIT 🟒
Library that helps with constructing difficult regular expressions. + +> **[RE2/J](https://github.com/google/re2j)** β˜… 1.3k 🟒
Java port of RE2 providing linear-time regular expression matching. + +> **[Sift](https://github.com/Mirkoddd/Sift)** β˜… 93 Apache-2.0 🟒
Type-safe, AST-based Regex Builder focused on readability and ReDoS prevention. + +
+ +
+REST Frameworks 13 projects + +_Frameworks specifically for creating RESTful services._ + +> **[Dropwizard](https://github.com/dropwizard/dropwizard)** β˜… 8.6k Apache-2.0 🟒
Opinionated framework for setting up modern web applications with Jetty, Jackson, Jersey and Metrics. + +> **[Elide](https://github.com/yahoo/elide)** β˜… 1.0k 🟒
Opinionated framework for JSON- or GraphQL-APIs based on a JPA data model. + +> **[hate](https://github.com/blackdoor/hate)** β˜… 25 MIT πŸ”΄
Builds hypermedia-friendly objects according to HAL specification. + +> **[Jersey](https://github.com/eclipse-ee4j/jersey)** β˜… 729 🟒
JAX-RS reference implementation. + +> **[OfficeFloor](https://github.com/officefloor/OfficeFloor)** β˜… 70 Apache-2.0 🟒
Spring Boot add-on that adds explicit function orchestration to REST endpoints, with each endpoint's steps, branches and error flows in one YAML file whose directory path maps to the URL. + +> **[openapi-generator](https://github.com/OpenAPITools/openapi-generator)** β˜… 26.6k Apache-2.0 🟒
Allows generation of API client libraries, SDKs, server stubs, documentation and configuration automatically given an OpenAPI Spec. + +> **[RESTEasy](https://github.com/resteasy/resteasy)** β˜… 1.1k Apache-2.0 🟒
Fully certified and portable implementation of the JAX-RS specification. + +> **[RestExpress](https://github.com/RestExpress/RestExpress)** β˜… 939 Apache-2.0 🟠
Thin wrapper on the JBoss Netty HTTP stack that provides scaling and performance. + +> **[Restlet Framework](https://github.com/restlet/restlet-framework-java)** β˜… 667 🟒
Pioneering framework with powerful routing and filtering capabilities, and a unified client and server API. + +> **[Spark](https://github.com/sparkjavateam/spark)** β˜… 14 Apache-2.0 πŸ”΄
Sinatra inspired framework. + +> **[Spring HATEOAS](https://github.com/spring-projects/spring-hateoas)** β˜… 1.1k Apache-2.0 🟒
Standalone and Spring support for building hypermedia-based APIs using HAL, HAL FORMS, Collection+JSON, ALPS and UBER. + +> **[springdoc-openapi](https://github.com/springdoc/springdoc-openapi)** β˜… 3.7k Apache-2.0 🟒
Automates the generation of API documentation using Spring Boot projects. + +> **[Swagger Java](https://swagger.io)** β˜… 8.6k Apache-2.0 🟒
Java libraries for generating, parsing and serving OpenAPI definitions. + +
+ +
+Science 13 projects + +_Libraries for scientific computing, analysis and visualization._ + +> **[BioJava](https://github.com/biojava/biojava)** β˜… 628 LGPL-2.1 🟒
Facilitates processing biological data by providing algorithms, file format parsers, sequencing and 3D visualization commonly used in bioinformatics. + +> **[Chart-FX](https://github.com/fair-acc/chart-fx)** β˜… 612 LGPL-3.0 🟠
Scientific charting library with focus on performance optimised real-time data visualisation at 25 Hz update rates for large data sets. + +> **[DataMelt](https://datamelt.org/)**
Environment for scientific computation, data analysis and data visualization. (GPL-3.0-or-later) + +> **[Erdos](https://github.com/Erdos-Graph-Framework/Erdos)** β˜… 128 MIT πŸ”΄
Modular, light and easy graph framework for theoretic algorithms. + +> **[Gephi](https://github.com/gephi/gephi)** β˜… 6.6k GPL-3.0 🟒
Cross-platform for visualizing and manipulating large graph networks. + +> **[JFreeChart](https://github.com/jfree/jfreechart)** β˜… 1.4k LGPL-2.1 🟠
2D chart library for Swing, JavaFX and server-side applications. + +> **[JGraphT](https://github.com/jgrapht/jgrapht)** β˜… 2.8k EPL-2.0 🟒
Graph library that provides mathematical graph-theory objects and algorithms. + +> **[jSciPy](https://github.com/hissain/jscipy)** β˜… 23 MIT 🟒
jSciPy is a Java library designed for scientific computing, offering functionalities inspired by popular scientific computing libraries. It currently provides modules for signal processing, including Butterworth filters, peak finding algorithms, and an RK4 solver for ordinary differential equations. + +> **[LogicNG](https://github.com/logic-ng/LogicNG)** β˜… 155 Apache-2.0 🟒
Library for creating, manipulating and solving Boolean and Pseudo-Boolean formulas. + +> **[Mines Java Toolkit](https://github.com/MinesJTK/jtk)** β˜… 87 Apache-2.0 πŸ”΄
Library for geophysical scientific computation, visualization and digital signal analysis. + +> **[Orekit](https://github.com/CS-SI/Orekit)** β˜… 286 Apache-2.0 🟒
A low level space flight dynamics library providing basic elements (orbits, dates, attitude, frames...) and various algorithms (conversions, propagations, pointing...) to handle them. + +> **[Orson-Charts](https://github.com/jfree/orson-charts)** β˜… 122 GPL-3.0 πŸ”΄
Generates a wide variety of 3D charts that can be displayed with Swing and JavaFX or exported to PDF, SVG, PNG and JPEG. + +> **[XChart](https://github.com/knowm/XChart)** β˜… 1.6k Apache-2.0 🟒
Light-weight library for plotting data. Many customizable chart types are available. + +
+ +
+Scripting 3 projects + +_Tools and runtimes for using Java or Java-like languages as scripts._ + +> **[JBang](https://github.com/jbangdev/jbang)** β˜… 1.8k MIT 🟒
JBang makes it easy to use Java for scripting. It lets you use a single file for code and dependency management and allows you to run it directly. + +> **[JPad](https://jpad.io)**
Snippet runner. + +> **[JQuick Java](https://github.com/paohaijiao/jquick-java)** β˜… 447 🟒
Java-like scripting language for dynamic rule engines with XML orchestration and Java interoperability. + +
+ + + +
+Security 26 projects + +_Libraries that handle security, authentication, authorization or session management._ + +> **[Apache Shiro](https://github.com/apache/shiro)** β˜… 4.4k Apache-2.0 🟒
Performs authentication, authorization, cryptography and session management. + +> **[Ayza](https://github.com/Hakky54/ayza)** β˜… 578 Apache-2.0 🟒
High-level SSL configuration builder for configuring HTTP clients and servers with SSL/TLS. + +> **[Bouncy Castle](https://github.com/bcgit/bc-java)** β˜… 2.7k MIT 🟒
All-purpose cryptographic library and JCA provider offering a wide range of functions, from basic helpers to PGP/SMIME operations. + +> **[Certificate Ripper](https://github.com/Hakky54/certificate-ripper)** β˜… 919 Apache-2.0 🟒
CLI tool and library for extracting and exporting server certificates from HTTPS endpoints. + +> **[Cryptomator](https://github.com/cryptomator/cryptomator)** β˜… 15.8k GPL-3.0 🟒
Multiplatform, transparent, client-side encryption of files in the cloud. + +> **[Dependency-Track](https://github.com/DependencyTrack/dependency-track)** β˜… 4.1k Apache-2.0 🟒
Software composition analysis platform for identifying supply-chain risk. + +> **[Jasypt Spring Boot](https://github.com/ulisesbocchio/jasypt-spring-boot)** β˜… 3.1k MIT 🟠
Integrates encrypted properties with Spring Boot applications. + +> **[jjwt](https://github.com/jwtk/jjwt)** β˜… 11.1k Apache-2.0 🟒
JSON web token for Java and Android. + +> **[Jwks RSA](https://github.com/auth0/jwks-rsa-java)** β˜… 206 MIT 🟒
JSON Web Key Set parser. + +> **[jwt-java](https://github.com/BastiaanJansen/jwt-java)** β˜… 14 MIT πŸ”΄
Easily create and parse JSON Web Tokens and create customized JWT validators using a fluent API. + +> **[Keycloak](https://github.com/keycloak/keycloak)** β˜… 36.0k Apache-2.0 🟒
Integrated SSO and IDM for browser apps and RESTful web services. + +> **[MOSS](https://github.com/mosscomputing/moss-java)** β˜… 0 🟒
Cryptographic signing for AI agents using ML-DSA-44 post-quantum signatures, creating audit trails for attribution and compliance. + +> **[Nbvcxz](https://github.com/GoSimpleLLC/nbvcxz)** β˜… 309 MIT 🟠
Advanced password strength estimation. + +> **[OpenAM](https://github.com/OpenIdentityPlatform/OpenAM)** β˜… 880 🟒
Access management solution that includes authentication, SSO, authorization, federation, entitlements and web services security. + +> **[OTP-Java](https://github.com/BastiaanJansen/OTP-Java)** β˜… 241 MIT 🟒
One-time password generator library according to RFC 4226 (HOTP) and RFC 6238 (TOTP). + +> **[OWASP Dependency-Check](https://github.com/dependency-check/DependencyCheck)** β˜… 7.6k Apache-2.0 🟒
Detects publicly disclosed vulnerabilities contained within a project's dependencies. + +> **[pac4j](https://github.com/pac4j/pac4j)** β˜… 2.5k Apache-2.0 🟒
Security engine. + +> **[Passay](https://github.com/vt-middleware/passay)** β˜… 313 🟠
Enforce password policy by validating candidate passwords against a configurable rule set. + +> **[Password4j](https://github.com/Password4j/password4j)** β˜… 430 Apache-2.0 🟠
User-friendly cryptographic library that supports Argon2, Bcrypt, Scrypt, PBKDF2 and various other cryptographic hash functions. + +> **[ScribeJava](https://github.com/scribejava/scribejava)** β˜… 5.5k MIT 🟒
OAuth client library supporting OAuth 1.0a, OAuth 2.0 and numerous providers. + +> **[SecurityBuilder](https://github.com/tersesystems/securitybuilder)** β˜… 48 Apache-2.0 πŸ”΄
Fluent Builder API for JCA and JSSE classes and especially X.509 certificates. + +> **[Spring Authorization Server](https://github.com/spring-projects/spring-authorization-server)** β˜… 5.1k Apache-2.0 🟒
Implements OAuth 2.1 and OpenID Connect authorization server specifications for Spring. + +> **[Themis](https://github.com/cossacklabs/themis)** β˜… 2.0k Apache-2.0 🟠
Multi-platform high-level cryptographic library provides easy-to-use encryption for protecting sensitive data: secure messaging with forward secrecy, secure data storage (AES256GCM); suits for building end-to-end encrypted applications. + +> **[Tink](https://github.com/tink-crypto/tink-java)** β˜… 297 Apache-2.0 🟒
Provides a simple and misuse-proof API for common cryptographic tasks. + +> **[Topaz](https://github.com/aserto-dev/topaz)** β˜… 1.4k Apache-2.0 🟒
Fine-grained authorization for applications with support for RBAC, ABAC, and ReBAC. + +> **[WebAuthn4J](https://github.com/webauthn4j/webauthn4j)** β˜… 582 Apache-2.0 🟒
Server-side WebAuthn and passkey verification library. + +
+ +
+Serialization 12 projects + +_Libraries that handle serialization with high efficiency._ + +> **[Apache Avro](https://github.com/apache/avro)** β˜… 3.3k Apache-2.0 🟒
Data interchange format with dynamic typing, untagged data, and absence of manually assigned IDs. + +> **[Apache Fory](https://github.com/apache/fory)** β˜… 4.4k Apache-2.0 🟒
High-performance object graph serialization framework with JIT and zero-copy support. + +> **[Apache Orc](https://github.com/apache/orc)** β˜… 769 Apache-2.0 🟒
Fast and efficient columnar storage format for Hadoop-based workloads. + +> **[Apache Parquet](https://github.com/apache/parquet-java)** β˜… 3.1k Apache-2.0 🟒
Columnar storage format based on assembly algorithms from Google's paper on Dremel. + +> **[Apache Thrift](https://github.com/apache/thrift)** β˜… 10.9k Apache-2.0 🟒
Data interchange format that originated at Facebook. + +> **[FlatBuffers](https://github.com/google/flatbuffers)** β˜… 26.3k Apache-2.0 🟒
Memory-efficient serialization library that can access serialized data without unpacking and parsing it. + +> **[Kryo](https://github.com/EsotericSoftware/kryo)** β˜… 6.5k BSD-3-Clause 🟒
Fast and efficient object graph serialization framework. + +> **[MessagePack](https://github.com/msgpack/msgpack-java)** β˜… 1.5k Apache-2.0 🟒
Efficient binary serialization format. + +> **[Protobuf](https://github.com/protocolbuffers/protobuf)** β˜… 71.7k 🟒
Google's data interchange format. + +> **[SBE](https://github.com/aeron-io/simple-binary-encoding)** β˜… 3.5k Apache-2.0 🟒
Simple Binary Encoding, one of the fastest message formats around. + +> **[Wire](https://github.com/square/wire)** β˜… 4.4k Apache-2.0 🟒
Clean, lightweight protocol buffers. + +> **[XMLBeam](https://github.com/SvenEwald/xmlbeam)** β˜… 76 Apache-2.0 🟠
Processes XML by using annotations or XPath within code. + +
+ +
+Server 4 projects + +_Servers specifically used to deploy applications._ + +> **[Apache Tomcat](https://github.com/apache/tomcat)** β˜… 8.2k Apache-2.0 🟒
Robust, all-round server for Servlet and JSP. + +> **[Apache TomEE](https://github.com/apache/tomee)** β˜… 476 Apache-2.0 🟒
Tomcat plus Java EE. + +> **[Jetty](https://github.com/jetty/jetty.project)** β˜… 4.1k 🟒
Provides a Web server and javax.servlet container, plus support for HTTP/2, WebSocket, OSGi, JMX, JNDI, JAAS and many other integrations. + +> **[WildFly](https://github.com/wildfly/wildfly)** β˜… 3.2k Apache-2.0 🟒
Formerly known as JBoss and developed by Red Hat with extensive Java EE support. + +
+ +
+Spreadsheet 7 projects + +_Libraries for reading, writing and generating spreadsheet files._ + +> **[Apache Fesod](https://github.com/apache/fesod)** β˜… 6.1k Apache-2.0 🟒
Memory-efficient library for reading and writing large spreadsheet files. + +> **[Apache POI](https://github.com/apache/poi)** β˜… 2.3k 🟒
Supports OOXML (XLSX, DOCX, PPTX) as well as OLE2 (XLS, DOC or PPT). + +> **[fastexcel](https://github.com/dhatim/fastexcel)** β˜… 908 🟒
High performance library to read and write large Excel (XLSX) worksheets. + +> **[jackson-dataformat-spreadsheet](https://github.com/scndry/jackson-dataformat-spreadsheet)** β˜… 23 Apache-2.0 🟒
Jackson dataformat module for reading and writing Excel (XLSX/XLS) as POJOs via `ObjectMapper`. + +> **[Jxls](https://github.com/jxlsteam/jxls)** β˜… 524 Apache-2.0 🟠
Generates Excel reports from spreadsheet templates. + +> **[Sheetz](https://github.com/chitralabs/sheetz)** β˜… 60 Apache-2.0 🟒
Reads and writes Excel, CSV and ODS files with annotation mapping, streaming, styling and validation. + +> **[zerocell](https://github.com/creditdatamw/zerocell)** β˜… 82 Apache-2.0 πŸ”΄
Annotation-based API for reading data from Excel sheets into POJOs with focus on reduced overhead. + +
+ +
+Template Engine 9 projects + +_Tools that substitute expressions in a template._ + +> **[Freemarker](https://github.com/apache/freemarker)** β˜… 1.1k Apache-2.0 🟒
Library to generate text output (HTML web pages, e-mails, configuration files, source code, etc.) based on templates and changing data. + +> **[Handlebars.java](https://github.com/jknack/handlebars.java)** β˜… 1.6k 🟒
Logicless and semantic Mustache templates. + +> **[Jamal](https://github.com/verhas/jamal)** β˜… 69 Apache-2.0 πŸ”΄
Extendable template engine embedded into Maven/JavaDoc, supporting multiple extensions (Groovy, Ruby, JavaScript, JShell, PlantUml) with support for snippet handling. + +> **[jstachio](https://github.com/jstachio/jstachio)** β˜… 330 BSD-3-Clause πŸ”΄
Typesafe Mustache templating engine. + +> **[jte](https://github.com/casid/jte)** β˜… 1.1k Apache-2.0 🟒
Compiles to classes, and uses an easy syntax, several features to make development easier and provides fast execution and a small footprint. + +> **[Pebble](https://github.com/PebbleTemplates/pebble)** β˜… 1.2k BSD-3-Clause 🟒
Inspired by Twig and separates itself with its inheritance feature and its easy-to-read syntax. It ships with built-in autoescaping for security and it includes integrated support for internationalization. + +> **[Rocker](https://github.com/fizzed/rocker)** β˜… 780 🟠
Optimized, memory efficient and speedy template engine producing statically typed, plain objects. + +> **[StringTemplate](https://github.com/antlr/stringtemplate4)** β˜… 1.0k πŸ”΄
Template engine for generating source code, web pages, emails, or any other formatted text output. + +> **[Thymeleaf](https://github.com/thymeleaf/thymeleaf)** β˜… 3.0k Apache-2.0 🟒
Aims to be a substitute for JSP and works for XML files. + +
+ +
+Testing 54 projects + +_Tools that test from model to the view._ + +#### BDD 6 projects + +_Testing for the software development process that emerged from TDD and was heavily influenced by DDD and OOAD._ + +> **[Cucumber](https://github.com/cucumber/cucumber-jvm)** β˜… 2.8k MIT 🟒
Provides a way to describe features in a plain language which customers can understand. + +> **[J8Spec](https://github.com/j8spec/j8spec)** β˜… 49 MIT πŸ”΄
Follows a Jasmine-like syntax. + +> **[JBehave](https://github.com/jbehave/jbehave-core)** β˜… 39 BSD-3-Clause 🟠
Extensively configurable framework that describes stories. + +> **[JGiven](https://github.com/TNG/JGiven)** β˜… 464 Apache-2.0 🟒
Provides a fluent API which allows for simpler composition. + +> **[Kensa](https://github.com/kensa-dev/kensa)** β˜… 22 Apache-2.0 🟒
Code-first BDD framework for Java and Kotlin that generates interactive HTML reports and sequence diagrams from test code. + +> **[Serenity BDD](https://github.com/serenity-bdd/serenity-core)** β˜… 754 🟒
Automated Acceptance testing and reporting library that works with Cucumber, JBehave and JUnit to make it easier to write high quality executable specifications. + +#### Fixtures 6 projects + +_Everything related to the creation and handling of random data._ + +> **[AutoParams](https://github.com/AutoParams/AutoParams)** β˜… 368 MIT 🟠
Supports generating test data or combining scenarios for parameterized tests. + +> **[Datafaker](https://github.com/datafaker-net/datafaker)** β˜… 1.8k Apache-2.0 🟒
Modern fake data generator forked from Java Faker. + +> **[Instancio](https://github.com/instancio/instancio)** β˜… 1.2k Apache-2.0 🟒
Automates data setup in unit tests by generating fully-populated, reproducible objects. Includes JUnit 5 extension. + +> **[jFairy](https://github.com/SkillPanel/jfairy)** β˜… 742 Apache-2.0 🟒
Fake data generator. + +> **[JMock](https://github.com/xcancloud/JMock)** β˜… 213 Apache-2.0 🟒
JMock is a high-performance data generation and simulation component library implemented in Java. + +> **[Randomized Testing](https://github.com/randomizedtesting/randomizedtesting)** β˜… 184 Apache-2.0 🟒
JUnit test runner and plugins for running JUnit tests with pseudo-randomness. + +#### Frameworks 7 projects + +_Provide environments to run tests for a specific use case._ + +> **[BitDive Java Agent](https://github.com/bitDive/java-producer)** β˜… 86 🟠
Java agent that captures runtime traces, SQL queries and HTTP payloads for BitDive testing. + +> **[jqwik](https://github.com/jqwik-team/jqwik)** β˜… 837 EPL-2.0 🟒
Engine for property-based testing built on JUnit 5. + +> **[JUnit](https://github.com/junit-team/junit-framework)** β˜… 7.0k EPL-2.0 🟒
Common testing framework. + +> **[PIT](https://github.com/hcoles/pitest)** β˜… 1.8k Apache-2.0 🟒
Fast mutation-testing framework for evaluating fault-detection abilities of existing JUnit or TestNG test suites. + +> **[Robolectric](https://github.com/robolectric/robolectric)** β˜… 6.0k 🟒
Runs Android tests on the JVM without an emulator or device. + +> **[selenium](https://github.com/SeleniumHQ/selenium)** β˜… 34.3k Apache-2.0 🟒
Browser automation framework and ecosystem. + +> **[Selenium Boot](https://github.com/seleniumboot/selenium-boot)** β˜… 11 🟒
Zero-boilerplate Selenium + TestNG framework with auto driver management, smart retry, self-healing locators, AI failure analysis, and a built-in HTML report. + +#### Integration 11 projects + +_Tools for integration, service and contract testing._ + +> **[Arquillian](https://github.com/arquillian/arquillian-core)** β˜… 387 Apache-2.0 🟒
Integration and functional testing platform for Java EE containers. + +> **[cdi-test](https://github.com/guhilling/cdi-test)** β˜… 31 Apache-2.0 🟒
JUnit extension for easy and efficient testing of CDI components. + +> **[Citrus](https://github.com/citrusframework/citrus)** β˜… 485 Apache-2.0 🟒
Integration testing framework that focuses on both client- and server-side messaging. + +> **[GreenMail](https://github.com/greenmail-mail-test/greenmail)** β˜… 740 Apache-2.0 🟒
In-memory email server for integration testing. Supports SMTP, POP3 and IMAP including SSL. + +> **[Hoverfly Java](https://github.com/SpectoLabs/hoverfly-java)** β˜… 176 Apache-2.0 🟒
Native bindings for Hoverfly, a proxy which allows you to simulate HTTP services. + +> **[Karate](https://github.com/karatelabs/karate)** β˜… 8.9k MIT 🟒
DSL that combines API test-automation, mocks and performance-testing making testing REST/HTTP services easy. + +> **[Pact JVM](https://github.com/pact-foundation/pact-jvm)** β˜… 1.1k Apache-2.0 🟒
Consumer-driven contract testing. + +> **[REST Assured](https://github.com/rest-assured/rest-assured)** β˜… 7.1k Apache-2.0 🟒
DSL for easy testing of REST/HTTP services. + +> **[Testcontainers](https://github.com/testcontainers/testcontainers-java)** β˜… 8.7k MIT 🟒
Provides throwaway instances of common databases, Selenium web browsers, or anything else that can run in a Docker container. + +> **[WebTau](https://github.com/testingisdocumenting/webtau)** β˜… 383 Apache-2.0 🟠
Test across REST-API, Graph QL, Browser, Database, CLI and Business Logic with consistent set of matchers and concepts. + +> **[weld-testing](https://github.com/weld/weld-testing)** β˜… 116 Apache-2.0 🟒
Set of test framework extensions (JUnit 4, JUnit 5, Spock) to enhance the testing of CDI components via Weld. Supports Weld 5. + +#### Matchers 4 projects + +_Libraries that provide custom matchers._ + +> **[AssertJ](https://github.com/assertj/assertj)** β˜… 2.8k Apache-2.0 🟒
Fluent assertions that improve readability. + +> **[JsonUnit](https://github.com/lukas-krecan/JsonUnit)** β˜… 1.0k Apache-2.0 🟒
Library that simplifies JSON comparison in tests. + +> **[Truth](https://github.com/google/truth)** β˜… 2.8k Apache-2.0 🟒
Google's fluent assertion and proposition framework. + +> **[XMLUnit](https://github.com/xmlunit/xmlunit)** β˜… 319 Apache-2.0 🟒
Simplifies testing for XML output. + +#### Miscellaneous 11 projects + +_Other stuff related to testing._ + +> **[Awaitility](https://github.com/awaitility/awaitility)** β˜… 4.0k Apache-2.0 🟠
DSL for synchronizing asynchronous operations. + +> **[ConcurrentUnit](https://github.com/jhalterman/concurrentunit)** β˜… 419 Apache-2.0 πŸ”΄
Toolkit for testing multi-threaded and asynchronous applications. + +> **[ConsoleCaptor](https://github.com/Hakky54/console-captor)** β˜… 35 Apache-2.0 🟒
Captures console output for unit testing purposes. + +> **[junit-dataprovider](https://github.com/TNG/junit-dataprovider)** β˜… 249 Apache-2.0 🟠
TestNG-like data provider/runner for JUnit. + +> **[junit-pioneer](https://github.com/junit-pioneer/junit-pioneer)** β˜… 617 EPL-2.0 🟒
JUnit 5 extension pack, pushing the frontiers on Jupiter. + +> **[log-capture](https://github.com/dm-drogeriemarkt/log-capture)** β˜… 16 MIT 🟒
Captures log entries and provides assertions for unit and integration testing. + +> **[LogCaptor](https://github.com/Hakky54/log-captor)** β˜… 432 Apache-2.0 🟒
Captures log entries for unit testing purposes. + +> **[Selfie](https://github.com/diffplug/selfie)** β˜… 101 Apache-2.0 🟒
Snapshot testing (inline and on disk). + +> **[skipper-java](https://github.com/get-skipper/skipper-java)** β˜… 4 MIT 🟠
Real-time test execution control via Google Spreadsheet, enabling instant toggle without code changes. + +> **[Stebz](https://github.com/stebz/stebz)** β˜… 20 MIT 🟒
Multi-approach framework for test steps managing. + +> **[test-watch-maven-plugin](https://github.com/albilu/test-watch-maven-plugin)** β˜… 1 MIT 🟒
Maven plugin providing Vitest-inspired watch mode for tests with smart selection and parallel execution. + +#### Mocking 6 projects + +_Tools which mock collaborators to help testing single, isolated units._ + +> **[EasyMock](https://github.com/easymock/easymock)** β˜… 832 🟒
EasyMock is a Java library that provides an easy way to use Mock Objects in unit testing. + +> **[JMockit](https://github.com/jmockit/jmockit1)** β˜… 473 πŸ”΄
Integration testing, API mocking and faking, and code coverage. + +> **[Mockito](https://github.com/mockito/mockito)** β˜… 15.4k MIT 🟒
Mocking framework that lets you write tests with a clean and simple API. + +> **[MockServer](https://github.com/mock-server/mockserver-monorepo)** β˜… 4.9k Apache-2.0 🟒
Allows mocking of systems integrated with HTTPS. + +> **[Moco](https://github.com/dreamhead/moco)** β˜… 4.4k MIT 🟒
Concise web services for stubs and mocks. + +> **[WireMock](https://github.com/wiremock/wiremock)** β˜… 7.3k Apache-2.0 🟒
Stubs and mocks web services. + +#### Performance 3 projects + +_Tools for load and performance testing._ + +> **[Apache JMeter](https://github.com/apache/jmeter)** β˜… 9.5k Apache-2.0 🟒
Functional testing and performance measurements. + +> **[Gatling](https://github.com/gatling/gatling)** β˜… 6.9k Apache-2.0 🟒
Load testing tool designed for ease of use, maintainability and high performance. + +> **[JMeter DSL.java](https://github.com/abstracta/jmeter-java-dsl)** β˜… 535 Apache-2.0 🟒
Load tests with JMeter as simple as a JUnit test. + +
+ +
+Utility 16 projects + +_Libraries which provide general utility functions._ + +> **[bucket4j](https://github.com/bucket4j/bucket4j)** β˜… 2.8k Apache-2.0 🟒
Rate limiting library based on token-bucket algorithm. + +> **[cactoos](https://github.com/yegor256/cactoos)** β˜… 778 MIT 🟒
Collection of object-oriented primitives. + +> **[fswatch](https://github.com/vorburger/ch.vorburger.fswatch)** β˜… 33 Apache-2.0 🟒
Micro library to watch for directory file system changes, simplifying java.nio.file.WatchService. + +> **[Guava](https://github.com/google/guava)** β˜… 51.5k Apache-2.0 🟒
Collections, caching, primitives support, concurrency libraries, common annotations, string processing, I/O, and more. + +> **[ISBN core](https://github.com/ladutsko/isbn-core)** β˜… 5 MIT 🟒
A small library that contains a representation object of ISBN-10 and ISBN-13 and tools to parse, validate and format one. + +> **[Java Diff Utils](https://github.com/java-diff-utils/java-diff-utils)** β˜… 1.5k Apache-2.0 🟒
Utilities for text or data comparison and patching. + +> **[Java UUID Generator](https://github.com/cowtowncoder/java-uuid-generator)** β˜… 934 Apache-2.0 🟒
Generates standard UUID versions including time-ordered UUIDv6 and UUIDv7. + +> **[java-refined](https://github.com/JunggiKim/java-refined)** β˜… 4 MIT 🟠
Zero-dependency refinement types for Java 8+ with type-safe wrappers covering numerics, strings, and collections. + +> **[java-util](https://github.com/jdereg/java-util)** β˜… 440 Apache-2.0 🟒
Zero-dependency, high-performance utilities featuring Converter (universal type conversion), DeepEquals, CaseInsensitiveMap, TTLCache, CompactMap, MultiKeyMap, and object graph traversal. + +> **[JEmoji](https://github.com/felldo/JEmoji)** β˜… 115 Apache-2.0 🟒
An auto-generated emoji library that provides type-safe direct access to emojis and alias support for Discord, Slack, GitHub and many more features. + +> **[Jimfs](https://github.com/google/jimfs)** β˜… 2.6k Apache-2.0 🟒
In-memory file system. + +> **[JKScope](https://github.com/evpl/jkscope)** β˜… 23 Apache-2.0 πŸ”΄
Java scope functions inspired by Kotlin. + +> **[PipelinR](https://github.com/sizovs/pipelinr)** β˜… 493 MIT 🟠
Small utility library for using handlers and commands with pipelines. + +> **[Semver4j](https://github.com/semver4j/semver4j)** β˜… 116 MIT 🟒
Lightweight library that helps you handling semantic versioning with different modes. + +> **[Underscore-java](https://github.com/javadev/underscore-java)** β˜… 550 MIT 🟒
Port of Underscore.js functions. + +> **[Zip4j](https://github.com/srikanth-lingala/zip4j)** β˜… 2.2k Apache-2.0 🟠
Reads, writes, encrypts and streams ZIP files. + +
+ +
+Version Managers 3 projects + +_Utilities that help create the development shell environment and switch between different Java versions._ + +> **[jabba](https://github.com/Jabba-Team/jabba)** β˜… 310 Apache-2.0 🟠
Java Version Manager inspired by nvm. Supports macOS, Linux and Windows. + +> **[jenv](https://github.com/jenv/jenv)** β˜… 6.6k MIT 🟠
Java Version Manager inspired by rbenv. Can configure globally or per project. Tested on Debian and macOS. + +> **[SDKMan](https://github.com/sdkman/sdkman-cli)** β˜… 6.8k Apache-2.0 🟒
Java Version Manager inspired by RVM and rbenv. Supports UNIX-based platforms and Windows. + +
+ +
+Web Crawling 5 projects + +_Libraries that analyze the content of websites._ + +> **[Apache Nutch](https://github.com/apache/nutch)** β˜… 3.3k Apache-2.0 🟒
Highly extensible, highly scalable web crawler for production environments. + +> **[crawlberg](https://github.com/xberg-io/crawlberg)** β˜… 150 MIT 🟒
Crawls and scrapes websites through a Java binding with Markdown conversion and optional browser rendering. + +> **[jsoup](https://github.com/jhy/jsoup)** β˜… 11.4k MIT 🟒
Scrapes, parses, manipulates and cleans HTML. + +> **[StormCrawler](https://github.com/apache/stormcrawler)** β˜… 991 Apache-2.0 🟒
SDK for building low-latency and scalable web crawlers. + +> **[webmagic](https://github.com/code4craft/webmagic)** β˜… 11.7k Apache-2.0 🟠
Scalable crawler with downloading, url management, content extraction and persistent. + +
+ +
+Web Frameworks 18 projects + +_Frameworks that handle the communication between the layers of a web application._ + +> **[ActiveJ](https://github.com/activej/activej)** β˜… 996 Apache-2.0 🟠
Lightweight asynchronous framework built from the ground up for developing high-performance web applications. + +> **[Apache Tapestry](https://github.com/apache/tapestry-5)** β˜… 136 Apache-2.0 🟒
Component-oriented framework for creating dynamic, robust, highly scalable web applications. + +> **[Apache Wicket](https://github.com/apache/wicket)** β˜… 794 Apache-2.0 🟒
Component-based web application framework similar to Tapestry, with a stateful GUI. + +> **[Blade](https://github.com/lets-blade/blade)** β˜… 5.9k Apache-2.0 🟒
Lightweight, modular framework that aims to be elegant and simple. + +> **[Bootique](https://github.com/bootique/bootique)** β˜… 1.4k Apache-2.0 🟒
Minimally opinionated framework for runnable apps. + +> **[Erupt](https://github.com/erupts/erupt)** β˜… 2.8k Apache-2.0 🟒
Annotation-Driven Low-Code & JPA Visualization. + +> **[Javalin](https://github.com/javalin/javalin)** β˜… 8.3k Apache-2.0 🟒
Microframework for web applications. + +> **[Jooby](https://github.com/jooby-project/jooby)** β˜… 1.8k Apache-2.0 🟒
Scalable, fast and modular micro-framework that offers multiple programming models. + +> **[Ninja](https://github.com/ninjaframework/ninja)** β˜… 1.9k Apache-2.0 🟠
Full-stack web framework. + +> **[Pippo](https://github.com/pippo-java/pippo)** β˜… 786 Apache-2.0 🟠
Small, highly modularized, Sinatra-like framework. + +> **[Play](https://github.com/playframework/playframework)** β˜… 12.6k Apache-2.0 🟒
Built on Akka, it provides predictable and minimal resource consumption (CPU, memory, threads) for highly-scalable applications in Java and Scala. + +> **[PrimeFaces](https://github.com/primefaces/primefaces)** β˜… 1.9k MIT 🟒
JSF framework with both free and commercial/support versions and frontend components. + +> **[Ratpack](https://github.com/ratpack/ratpack)** β˜… 1.9k 🟒
Set of libraries that facilitate fast, efficient, evolvable and well-tested HTTP applications. + +> **[Spring Boot](https://github.com/spring-projects/spring-boot)** β˜… 81.2k Apache-2.0 🟒
Framework for creating stand-alone, production-grade Spring applications. + +> **[Takes](https://github.com/yegor256/takes)** β˜… 876 MIT 🟒
Opinionated web framework which is built around the concepts of True Object-Oriented Programming and immutability. + +> **[tinystruct](https://github.com/tinystruct/tinystruct)** β˜… 352 Apache-2.0 🟒
Lightweight, pluggable framework for building Java applications with CLI, HTTP, and modular extension support. + +> **[Vaadin](https://vaadin.com)** β˜… 1.7k 🟒
Full-stack Java platform for building browser applications with server-side components. + +> **[WebForms Core](https://github.com/webforms-core)**
A technology for managing HTML tags from the server. + +
+ +
+Workflow Orchestration Engines 7 projects + +_Engines for orchestrating long-running workflows and business processes._ + +> **[Activiti](https://github.com/Activiti/Activiti)** β˜… 10.5k Apache-2.0 🟒
Embeddable BPMN workflow and business process engine. + +> **[Apache DolphinScheduler](https://github.com/apache/dolphinscheduler)** β˜… 14.4k Apache-2.0 🟒
Distributed workflow orchestration platform with visual and API-driven scheduling. + +> **[Cadence Java Client](https://github.com/cadence-workflow/cadence-java-client)** β˜… 152 Apache-2.0 🟒
Java client and workflow framework for the Cadence orchestration service. + +> **[Conductor](https://github.com/conductor-oss/conductor)** β˜… 32.0k Apache-2.0 🟒
Event-driven workflow engine for distributed applications and AI agents. + +> **[flowable](https://github.com/flowable/flowable-engine)** β˜… 9.4k Apache-2.0 🟒
Compact and efficient workflow and business process management platform. + +> **[Maestro](https://github.com/Netflix/maestro)** β˜… 3.8k Apache-2.0 🟒
Workflow orchestration engine developed by Netflix. + +> **[Temporal Java SDK](https://github.com/temporalio/sdk-java)** β˜… 424 Apache-2.0 🟒
Java SDK for writing durable workflows and activities on Temporal. + +
+ +## Resources + + + +
+Communities 3 links + +_Active discussions._ + +> **[foojay.io](https://foojay.io)** + +> **[r/java](https://www.reddit.com/r/java/)**
Subreddit for the Java community. + +> **[Stack Overflow](https://stackoverflow.com/questions/tagged/java)**
Question/answer platform. + +
+ +
+Guides and References 10 links + +_Guides, tutorials, examples and practical references for Java developers._ + +> **[Design Patterns](https://github.com/iluwatar/java-design-patterns)**
Implementation and explanation of the most common design patterns. + +> **[FizzBuzz Enterprise Edition](https://github.com/EnterpriseQualityCoding/FizzBuzzEnterpriseEdition)**
No-nonsense implementation of FizzBuzz made by serious businessmen for serious business purposes. (No explicit license) + +> **[Google Java Style](https://google.github.io/styleguide/javaguide.html)** + +> **[Java Algorithms and Clients](https://algs4.cs.princeton.edu/code)** + +> **[Java Concurrency Checklist](https://github.com/code-review-checklists/java-concurrency)** + +> **[Java Developer Roadmap](https://github.com/s4kibs4mi/java-developer-roadmap)** + +> **[Java Evolved](https://github.com/javaevolved/javaevolved.github.io)**
Side-by-side comparisons of legacy and modern Java patterns. + +> **[Modern Java - A Guide to Java 8](https://github.com/winterbe/java8-tutorial)**
Popular Java 8 guide. + +> **[TheCodeForge Java Tutorials](https://thecodeforge.io/java/)** + +> **[Which JDK](https://github.com/whichjdk/whichjdk.com)**
Overview of common JVMs with pros and cons. + +
+ +
+Influential Books 7 links + +_Books that made a big impact and are still worth reading._ + +> **[Core Java Volume I--Fundamentals](https://www.amazon.com/Core-Java-I-Fundamentals-10th/dp/0134177304)** + +> **[Core Java, Volume II--Advanced Features](https://www.amazon.com/Core-Java-II-Advanced-Features-10th/dp/0134177290)** + +> **[Effective Java (3rd Edition)](https://www.amazon.com/Effective-Java-3rd-Joshua-Bloch/dp/0134685997)** + +> **[Head First Java (3rd Edition)](https://www.oreilly.com/library/view/head-first-java/9781492091646/)** + +> **[Java Concurrency in Practice](https://www.amazon.com/Java-Concurrency-Practice-Brian-Goetz/dp/0321349601)** + +> **[The Well-Grounded Java Developer (2nd Edition)](https://www.manning.com/books/the-well-grounded-java-developer-second-edition)** + +> **[Thinking in Java](https://www.amazon.com/Thinking-Java-Edition-Bruce-Eckel/dp/0131872486)** + +
+ +
+Podcasts and Screencasts 5 links + +_Something to look at or listen to while programming._ + +> **[140 Second Ducklings](https://twitter.com/debugagent/status/1491075324805001219)**
Short videos on Twitter explaining Java debugging in depth. + +> **[A Bootiful Podcast](https://bootifulpodcast.fm)** + +> **[Foojay Podcast](https://foojay.io/today/category/podcast/)** + +> **[Inside Java](https://inside.java/podcast)**
Official podcast. + +> **[Java Off Heap](https://www.javaoffheap.com)** + +
+ +
+People 35 links + +_Active accounts to follow. Descriptions from their socials._ + +> **[Adam Bien](https://twitter.com/AdamBien)**
Freelance author, JavaOne Rockstar speaker, consultant, Java Champion. + +> **[Aleksey ShipilΓ«v](https://twitter.com/shipilev)**
Performance geek, benchmarking czar, concurrency bug hunter. + +> **[Antonio Goncalves](https://twitter.com/agoncal)**
Java Champion, JUG Leader, Devoxx France, Java EE 6/7, JCP, Author. + +> **[Arun Gupta](https://twitter.com/arungupta)**
Java Champion, JavaOne Rockstar, JUG Leader, Devoxx4Kids-er, VP of Developer Advocacy at Couchbase. + +> **[Brian Goetz](https://bsky.app/profile/briangoetz.bsky.social)**
Java Language Architect at Oracle. + +> **[Bruno Borges](https://twitter.com/brunoborges)**
Product Manager/Java Jock at Oracle. + +> **[Chris Engelbert](https://twitter.com/noctarius2k)**
Open Source Enthusiast, Speaker, Developer, Developer Advocacy at TimescaleDB. + +> **[Chris Richardson](https://bsky.app/profile/crichardson.bsky.social)**
Software architect, consultant, and serial entrepreneur, Java Champion, JavaOne Rock Star, \*POJOs in Action- author. + +> **[Ed Burns](https://twitter.com/edburns)**
Consulting Member of the Technical Staff at Oracle. + +> **[Eugen Paraschiv](https://twitter.com/baeldung)**
Author of the Spring Security Course. + +> **[Heinz Kabutz](https://twitter.com/heinzkabutz)**
Java Champion, speaker, author of The Java Specialists' Newsletter, concurrency performance expert. + +> **[Holly Cummins](https://twitter.com/holly_cummins)**
Technical Lead of IBM London's Bluemix Garage, Java Champion, developer, author, JavaOne rockstar. + +> **[James Weaver](https://twitter.com/JavaFXpert)**
Java/JavaFX/IoT developer, author and speaker. + +> **[Java](https://twitter.com/java)**
Official Java Twitter account. + +> **[Javin Paul](https://twitter.com/javinpaul)**
Well-known Java blogger. + +> **[Josh Long](https://twitter.com/starbuxman)**
Spring Advocate at Pivotal, author of O'Reilly's Cloud Native Java- and Building Microservices with Spring Boot, JavaOne Rock Star. + +> **[Lukas Eder](https://bsky.app/profile/lukaseder.bsky.social)**
Java Champion, speaker, Founder and CEO Data Geekery (jOOQ). + +> **[Mani Sarkar](https://twitter.com/theNeomatrix369)**
Java champion, Polyglot, Software Crafter involved with @graalvm, AI/ML/DL, Data Science, Developer communities, speaker & blogger. Creator of couple of awesome lists like this one. + +> **[Mario Fusco](https://twitter.com/mariofusco)**
RedHatter, JUG coordinator, frequent speaker and author. + +> **[Mark Heckler](https://twitter.com/MkHeck)**
Pivotal Principal Technologist and Developer Advocate, conference speaker, published author, and Java Champion, focusing on Internet of Things and the cloud. + +> **[Markus Eisele](https://twitter.com/myfear)**
Java EE evangelist, Red Hat. + +> **[Martijn Verburg](https://twitter.com/karianna)**
London JUG co-leader, speaker, author, Java Champion and much more. + +> **[Martin Thompson](https://twitter.com/mjpt777)**
Pasty faced performance gangster. + +> **[Monica Beckwith](https://twitter.com/mon_beck)**
Performance consultant, JavaOne Rock Star. + +> **[OpenJDK](https://twitter.com/OpenJDK)**
Official OpenJDK account. + +> **[Peter Lawrey](https://twitter.com/PeterLawrey)**
Peter Lawrey, Java performance expert. + +> **[Randy Shoup](https://twitter.com/randyshoup)**
Stitch Fix VP Engineering, speaker, JavaOne Rock Star. + +> **[Reza Rahman](https://twitter.com/reza_rahman)**
Java EE/GlassFish/WebLogic evangelist, author, speaker, open source hacker. + +> **[Sander Mak](https://twitter.com/Sander_Mak)**
Java Champion, author. + +> **[Simon Maple](https://twitter.com/sjmaple)**
Java Champion, VirtualJUG founder, LJC leader, RebelLabs author. + +> **[Spencer Gibb](https://twitter.com/spencerbgibb)**
Software Engineer, Dad, Geek, Co-founder and Lead of Spring Cloud Core @pivotal. + +> **[Stephen Colebourne](https://bsky.app/profile/jodastephen.bsky.social)**
Java Champion, speaker. + +> **[Trisha Gee](https://twitter.com/trisha_gee)**
Java Champion and speaker. + +> **[Venkat Subramaniam](https://twitter.com/venkat_s)**
Author, University of Houston professor, MicroSoft MVP award recipient, JavaOne Rock Star, Java Champion. + +> **[Vlad Mihalcea](https://twitter.com/vlad_mihalcea)**
Java Champion working on Hypersistence Optimizer, database aficionado, author of High-Performance Java Persistence book. + +
+ +
+Websites 12 links + +_Sites to read._ + +> **[Baeldung](https://www.baeldung.com)** + +> **[Dzone](https://dzone.com)** + +> **[InfoQ](https://www.infoq.com)** + +> **[Java, SQL, and jOOQ](https://blog.jooq.org)** + +> **[java.libhunt.com](https://java.libhunt.com)** + +> **[Java.net](https://community.oracle.com/community/java)** + +> **[Javalobby](https://dzone.com/java-jdk-development-tutorials-tools-news)** + +> **[JavaWorld](https://www.javaworld.com)** + +> **[JAXenter](https://jaxenter.com)** + +> **[RebelLabs](https://zeroturnaround.com/rebellabs)** + +> **[TheServerSide.com](https://www.theserverside.com)** + +> **[Vanilla Java](https://vanilla-java.github.io)** -### Awesome Lists - -*Awesome lists related to the Java & JVM ecosystem.* - -- [Awesome Gradle Plugins](https://github.com/ksoichiro/awesome-gradle) -- [AwesomeJavaFX](https://github.com/mhrimaz/AwesomeJavaFX) -- [Awesome JVM](https://github.com/deephacks/awesome-jvm) -- [Awesome Microservices](https://github.com/mfornos/awesome-microservices) -- [Awesome REST](https://github.com/marmelab/awesome-rest) -- [Awesome Selenium](https://github.com/christian-bromann/awesome-selenium) -- [ciandcd](https://github.com/ciandcd/awesome-ciandcd) -- [Useful Java Links](https://github.com/Vedenin/useful-java-links) - -### Communities - -*Active discussions.* - -- [r/java](https://www.reddit.com/r/java) - Subreddit for the Java community. -- [stackoverflow](https://stackoverflow.com/questions/tagged/java) - Question/answer platform. -- [VirtualJUG](https://virtualjug.com) - Virtual Java User Group. - -### Frontends - -*Websites that provide a frontend for this list. Please note, there won't be an official website. We don't associate with a particular website and everybody is allowed to create one.* - -- [java.libhunt.com](https://java.libhunt.com) - -### Influential Books - -*Books that made a big impact and are still worth reading.* - -- [Core Java Volume I--Fundamentals](https://www.amazon.com/Core-Java-I-Fundamentals-10th/dp/0134177304) -- [Core Java, Volume II--Advanced Features](https://www.amazon.com/Core-Java-II-Advanced-Features-10th/dp/0134177290) -- [Effective Java (3rd Edition)](https://www.amazon.com/Effective-Java-3rd-Joshua-Bloch/dp/0134685997) -- [Java Concurrency in Practice](https://www.amazon.com/Java-Concurrency-Practice-Brian-Goetz/dp/0321349601) -- [Thinking in Java](https://www.amazon.com/Thinking-Java-Edition-Bruce-Eckel/dp/0131872486) - -### Podcasts and Screencasts - -*Something to look at or listen to while programming.* - -- [Java Off Heap](http://www.javaoffheap.com) -- [Marco Behler's Screencasts](https://www.marcobehler.com/series) - Screencasts about modern Java development. -- [The Java Council](https://virtualjug.com/podcast) -- [The Java Posse](http://www.javaposse.com) - Discontinued as of 02/2015. - -### Twitter - -*Active accounts to follow. Descriptions from Twitter.* - -- [Adam Bien](https://twitter.com/AdamBien) - Freelance author, JavaOne Rockstar speaker, consultant, Java Champion. -- [Aleksey ShipilΓ«v](https://twitter.com/shipilev) - Performance geek, benchmarking czar, concurrency bug hunter. -- [Antonio Goncalves](https://twitter.com/agoncal) - Java Champion, JUG Leader, Devoxx France, Java EE 6/7, JCP, Author. -- [Arun Gupta](https://twitter.com/arungupta) - Java Champion, JavaOne Rockstar, JUG Leader, Devoxx4Kids-er, VP of Developer Advocacy at Couchbase. -- [Brian Goetz](https://twitter.com/BrianGoetz) - Java Language Architect at Oracle. -- [Bruno Borges](https://twitter.com/brunoborges) - Product Manager/Java Jock at Oracle. -- [Chris Richardson](https://twitter.com/crichardson) - Software architect, consultant, and serial entrepreneur, Java Champion, JavaOne Rock Star, *POJOs in Action- author. -- [Ed Burns](https://twitter.com/edburns) - Consulting Member of the Technical Staff at Oracle. -- [Eugen Paraschiv](https://twitter.com/baeldung) - Author of the Spring Security Course. -- [Heinz Kabutz](https://twitter.com/heinzkabutz) - Java Champion, speaker, author of The Java Specialists' Newsletter, concurrency performance expert. -- [Holly Cummins](https://twitter.com/holly_cummins) - Technical Lead of IBM London's Bluemix Garage, Java Champion, developer, author, JavaOne rockstar. -- [James Weaver](https://twitter.com/JavaFXpert) - Java/JavaFX/IoT developer, author and speaker. -- [Java EE](https://twitter.com/Java_EE) - Official Java EE Twitter account. -- [Java Magazine](https://twitter.com/Oraclejavamag) - Official Java Magazine account. -- [Java](https://twitter.com/java) - Official Java Twitter account. -- [Javin Paul](https://twitter.com/javinpaul) - Well-known Java blogger. -- [Josh Long](https://twitter.com/starbuxman) - Spring Advocate at Pivotal, author of O'Reilly's Cloud Native Java- and Building Microservices with Spring Boot, JavaOne Rock Star. -- [Lukas Eder](https://twitter.com/lukaseder) - Java Champion, speaker, JUG.ch co-leader, Founder and CEO Data Geekery (jOOQ). -- [Mario Fusco](https://twitter.com/mariofusco) - RedHatter, JUG coordinator, frequent speaker and author. -- [Mark Heckler](https://twitter.com/MkHeck) - Pivotal Principal Technologist and Developer Advocate, conference speaker, published author, and Java Champion, focusing on Internet of Things and the cloud. -- [Mark Reinhold](https://twitter.com/mreinhold) - Chief Architect, Java Platform Group, Oracle. -- [Markus Eisele](https://twitter.com/myfear) - Java EE evangelist, Red Hat. -- [Martijn Verburg](https://twitter.com/karianna) - London JUG co-leader, speaker, author, Java Champion and much more. -- [Martin Thompson](https://twitter.com/mjpt777) - Pasty faced performance gangster. -- [Monica Beckwith](https://twitter.com/mon_beck) - Performance consultant, JavaOne Rock Star. -- [OpenJDK](https://twitter.com/OpenJDK) - Official OpenJDK account. -- [Peter Lawrey](https://twitter.com/PeterLawrey) - Peter Lawrey, Java performance expert. -- [Randy Shoup](https://twitter.com/randyshoup) - Stitch Fix VP Engineering, speaker, JavaOne Rock Star. -- [Reza Rahman](https://twitter.com/reza_rahman) - Java EE/GlassFish/WebLogic evangelist, author, speaker, open source hacker. -- [Simon Maple](https://twitter.com/sjmaple) - Java Champion, VirtualJUG founder, LJC leader, RebelLabs author. -- [Stephen Colebourne](https://twitter.com/jodastephen) - Java Champion, speaker. -- [Trisha Gee](https://twitter.com/trisha_gee) - Java Champion and speaker. -- [Venkat Subramaniam](https://twitter.com/venkat_s) - Author, University of Houston professor, MicroSoft MVP award recipient, JavaOne Rock Star, Java Champion. - -### Websites - -*Sites to read.* - -- [Google Java Style](https://google.github.io/styleguide/javaguide.html) -- [InfoQ](https://www.infoq.com) -- [Java Algorithms and Clients](https://algs4.cs.princeton.edu/code) -- [Java, SQL, and jOOQ](https://blog.jooq.org) -- [Java.net](https://community.oracle.com/community/java) -- [Javalobby](https://dzone.com/java-jdk-development-tutorials-tools-news) -- [JavaWorld](https://www.javaworld.com) -- [JAXenter](https://jaxenter.com) -- [RebelLabs](https://zeroturnaround.com/rebellabs) -- [The Takipi Blog](http://blog.takipi.com) -- [TheServerSide.com](http://www.theserverside.com) -- [Vanilla Java](https://vanilla-java.github.io) -- [Voxxed](https://www.voxxed.com) +
## Contributing -Contributions are very welcome! +> **[Suggest a project or resource](https://github.com/akullpp/awesome-java/edit/main/README_SOURCE.md)** Β· [Contribution guidelines](CONTRIBUTING.md) +> +> Add one Markdown entry under the appropriate category and open one pull request.
+> Ordering, counts and GitHub statistics are generated automatically. -Please have a look at the [CONTRIBUTING](https://github.com/akullpp/awesome-java/blob/master/CONTRIBUTING.md) guidelines. +## License -[c]: https://cdn.rawgit.com/akullpp/23246ca832bda82bb505230bf3538e2a/raw/d9bcdb769bf025292f9c6bc1290f01f1fcd1f864/commercial.svg +Catalog and documentation: [CC BY-SA 4.0](LICENSE).
+Automation code and configuration: [MIT](LICENSE-CODE). diff --git a/README_SOURCE.md b/README_SOURCE.md new file mode 100644 index 00000000..916ebcdd --- /dev/null +++ b/README_SOURCE.md @@ -0,0 +1,1397 @@ +# Awesome Java [![Awesome](https://awesome.re/badge.svg)](https://awesome.re) + +A curated list of noteworthy Java frameworks, libraries, tools and resources. + + + +## Projects + +### Architecture + +_Frameworks and libraries that help implementing and verifying design and architecture concepts._ + +- [ArchUnit](https://github.com/TNG/ArchUnit) - Test library for specifying and asserting architecture rules. +- [jMolecules](https://github.com/xmolecules/jmolecules) - Annotations and interfaces to express design and architecture concepts in code. +- [jQAssistant](https://github.com/jQAssistant/jqassistant) - Static code analysis with Neo4J-based query language. +- [Taikai](https://github.com/enofex/taikai) - ArchUnit extension with predefined architecture rules for common Java technologies. + +### Artificial Intelligence + +_Frameworks for building applications with AI, agents and knowledge-based systems._ + +- [Anahata ASI](https://github.com/anahata-os/anahata-asi) - Java agent container with local LLM adapters, stateful tool execution, context management and IDE integration. +- [AgentScope Java](https://github.com/agentscope-ai/agentscope-java) - Framework for building distributed, long-running AI agents with tool execution, persistence and multi-agent orchestration. +- [A2A Java SDK](https://github.com/a2aproject/a2a-java) - Official Java SDK for the Agent2Agent protocol. +- [Dokimos](https://github.com/dokimos-dev/dokimos) - Evaluation framework for LLM and AI-agent applications that scores responses, validates tool calls and execution traces, and catches quality regressions in CI. +- [Google Gen AI Java SDK](https://github.com/googleapis/java-genai) - Official Java SDK for integrating Google generative AI models. +- [JADE](https://jade.tilab.com) - Framework and environment for building and debugging multi-agent systems. (LGPL-2.0-only) +- [JamJet](https://github.com/jamjet-labs/jamjet) - Agent runtime with a Java SDK for building AI agents, supporting graph-based workflow orchestration, multi-agent coordination, and MCP/A2A protocols. +- [LangChain4j](https://github.com/langchain4j/langchain4j) - Simplifies integration of LLMs with unified APIs and a comprehensive toolbox. +- [liter-llm](https://github.com/xberg-io/liter-llm) - Provides a Java binding for a unified LLM API client across multiple providers. +- [MCP Java SDK](https://github.com/modelcontextprotocol/java-sdk) - Enables applications to interact with AI models and tools through a standardized interface (i.e. Model Context Protocol), supporting both synchronous and asynchronous communication patterns. +- [ProtΓ©gΓ©](https://github.com/protegeproject/protege) - Provides an ontology editor and a framework to build knowledge-based systems. +- [Regulus](https://github.com/neul-labs/regulus) - Google ADK plugin suite that adds runtime compliance profiles, audit envelopes and GRC adapters for regulated Java AI agents. +- [simple-openai](https://github.com/sashirestela/simple-openai) - Library to use the OpenAI API (and compatible ones) in the simplest possible way. +- [Spring AI](https://github.com/spring-projects/spring-ai) - Application framework for AI engineering for Spring. +- [Spring AI Alibaba](https://github.com/alibaba/spring-ai-alibaba) - Agentic AI framework built on Spring AI with model, tool, RAG and workflow integrations. + +### Bean Mapping + +_Frameworks that ease bean mapping._ + +- [Immuto](https://github.com/karunarathnad/immuto) - Annotation processor that generates type-safe mapper implementations for Java Records using canonical constructors, with zero runtime reflection. +- [MapStruct](https://github.com/mapstruct/mapstruct) - Code generator that simplifies mappings between different bean types, based on a convention-over-configuration approach. +- [ModelMapper](https://github.com/modelmapper/modelmapper) - Intelligent object mapping library that automatically maps objects to each other. +- [reMap](https://github.com/remondis-it/remap) - Lambda and method handle-based mapping which requires code and not annotations if objects have different names. + +### Bot Development + +_Libraries and frameworks for building chatbots and messaging-platform bots._ + +- [JBot](https://github.com/rampatra/jbot) - Framework for building chatbots. +- [JDA](https://github.com/discord-jda/JDA) - Wrapping of the Discord REST API and its WebSocket events. +- [Nyagram](https://github.com/kaleert/nyagram) - Reactive, type-safe framework for Telegram bots based on Spring Boot 3 and Java 21. +- [TelegramBots](https://github.com/rubenlagus/TelegramBots) - Java library for building bots with the Telegram Bot API. + +### Build + +_Tools that handle the build cycle and dependencies of an application._ + +- [Apache Maven](https://github.com/apache/maven) - Declarative build and dependency management that favors convention over configuration. It might be preferable to Apache Ant, which uses a rather procedural approach and can be difficult to maintain. +- [Bazel](https://github.com/bazelbuild/bazel) - Tool from Google that builds code quickly and reliably. +- [Buck2](https://github.com/facebook/buck2) - Encourages the creation of small, reusable modules consisting of code and resources. +- [Dependency Analysis Gradle Plugin](https://github.com/autonomousapps/dependency-analysis-gradle-plugin) - Analyzes JVM and Android builds and recommends dependency and plugin changes. +- [Docker Maven Plugin](https://github.com/fabric8io/docker-maven-plugin) - Builds and runs Docker images from Maven. +- [Eclipse JKube](https://github.com/eclipse-jkube/jkube) - Maven and Gradle plugins for building and deploying Java applications on Kubernetes. +- [Frontend Maven Plugin](https://github.com/eirslett/frontend-maven-plugin) - Installs and runs Node.js frontend tooling from Maven builds. +- [git-commit-id Maven Plugin](https://github.com/git-commit-id/git-commit-id-maven-plugin) - Exposes Git revision information to Maven builds and applications. +- [Gradle](https://github.com/gradle/gradle) - Incremental builds programmed via Groovy instead of declaring XML. Works well with Maven's dependency management. +- [Jib](https://github.com/GoogleContainerTools/jib) - Builds optimized container images for Java applications without a Docker daemon. +- [Javadoc Publisher](https://github.com/MathieuSoysal/Javadoc-publisher.yml) - Generate Javadoc from your maven/gradle project and deploy it automatically on GitHub Page. +- [jar-cart](https://github.com/Sudhanshu-Ambastha/jar-cart) - A modern, zero-configuration package manager and runner for the Java ecosystem written in Go, focusing on developer productivity and build speed. +- [Maven Wrapper](https://github.com/apache/maven-wrapper) - Analogue of Gradle Wrapper for Maven, allowing projects to build without a preinstalled Maven. +- [Polyglot for Maven](https://github.com/takari/polyglot-maven) - Extensions for Maven 3.3.1+ that allows writing the POM model in dialects other than XML. +- [ReleaseRun](https://github.com/Releaserun/releaserun-cli) - Dependency health checker for pom.xml and Gradle projects that scans for CVEs and outdated packages. +- [Shadow](https://github.com/GradleUp/shadow) - Gradle plugin for creating and transforming executable fat JARs. + +### Bytecode Manipulation + +_Libraries to manipulate bytecode programmatically._ + +- [ASM](https://asm.ow2.io) - All-purpose, low-level bytecode manipulation and analysis. +- [Byte Buddy](https://github.com/raphw/byte-buddy) - Further simplifies bytecode generation with a fluent API. +- [bytecode-viewer](https://github.com/Konloch/bytecode-viewer) - Java 8 Jar & Android APK reverse engineering suite. +- [Byteman](https://github.com/bytemanproject/byteman) - Manipulate bytecode at runtime via DSL (rules); mainly for testing/troubleshooting. (LGPL-2.1-or-later) +- [Javassist](https://github.com/jboss-javassist/javassist) - Tries to simplify bytecode editing. +- [Maker](https://github.com/cojen/maker) - Provides low level bytecode generation. +- [Recaf](https://github.com/Col-E/Recaf) - JVM reverse engineering toolkit, essentially an IDE for Java bytecode. + +### Caching + +_Libraries that provide caching facilities._ + +- [cache2k](https://github.com/cache2k/cache2k) - In-memory high performance caching library. +- [Caffeine](https://github.com/ben-manes/caffeine) - High-performance, near-optimal caching library. +- [Ehcache](https://github.com/ehcache/ehcache3) - Distributed general-purpose cache. +- [Infinispan](https://github.com/infinispan/infinispan) - Highly concurrent key/value datastore used for caching. +- [JetCache](https://github.com/alibaba/jetcache) - Java cache framework with local and distributed caching, annotations and asynchronous APIs. + +### CLI + +_Libraries for everything related to the CLI._ + +#### Argument Parsing + +_Libraries to assist with parsing command line arguments._ + +- [Airline](https://github.com/rvesse/airline) - Annotation-based framework for parsing Git-like command-line arguments. +- [JCommander](https://github.com/cbeust/jcommander) - Command-line argument-parsing framework with custom types and validation via implementing interfaces. +- [jbock](https://github.com/jbock-java/jbock) - Reflectionless command line parser. +- [JLine](https://github.com/jline/jline3) - Includes features from modern shells like completion or history. +- [picocli](https://github.com/remkop/picocli) - ANSI colors and styles in usage help with annotation-based POSIX/GNU/any syntax, subcommands, strong typing for both options and positional args. + +#### Text-Based User Interfaces + +_Libraries that provide TUI frameworks, or building blocks related functions._ + +- [AliveJTUI](https://github.com/yehorsyrin/alivejTUI) - Declarative, React-style TUI library for building terminal UIs as component trees with diff-based rendering, focus management, and themes. +- [Jansi](https://github.com/fusesource/jansi) - ANSI escape codes to format console output. +- [Jexer](https://gitlab.com/AutumnMeowMeow/jexer) - Advanced console (and Swing) text user interface (TUI) library, with mouse-draggable windows, built-in terminal window manager, and sixel image support. Looks like [Turbo Vision](https://en.wikipedia.org/wiki/Turbo_Vision). +- [Lanterna](https://github.com/mabe02/lanterna) - Easy console text-GUI library, similar to curses. + +### Cloud + +_Libraries to integrate or use cloud-specific features._ + +- [AWS SDK for Java 2.x](https://github.com/aws/aws-sdk-java-v2) - Official Java APIs for interacting with Amazon Web Services. +- [Google Cloud Client Libraries](https://github.com/googleapis/google-cloud-java) - Client libraries for accessing Google Cloud services from Java applications. +- [Java Operator SDK](https://github.com/operator-framework/java-operator-sdk) - SDK for implementing Kubernetes operators in Java. +- [kubernetes-client](https://github.com/fabric8io/kubernetes-client) - Client provides access to the full Kubernetes & OpenShift REST APIs via a fluent DSL. +- [Kubernetes Java Client](https://github.com/kubernetes-client/java) - Official Java client for the Kubernetes API. +- [minio-java](https://github.com/minio/minio-java) - Provides simple APIs to access any Amazon S3-compatible object storage server. + +### Code Analysis + +_Tools that provide metrics and quality measurements._ + +- [Checkstyle](https://github.com/checkstyle/checkstyle) - Static analysis of coding conventions and standards. +- [Error Prone](https://github.com/google/error-prone) - Catches common programming mistakes as compile-time errors. +- [Error Prone Support](https://github.com/PicnicSupermarket/error-prone-support) - Error Prone extensions: extra bug checkers and a large battery of Refaster templates. +- [Infer](https://github.com/facebook/infer) - Modern static analysis tool for verifying the correctness of code. +- [JSpecify](https://github.com/jspecify/jspecify) - Standardized nullness annotations designed to work uniformly across various Java IDEs, compilers, and static analysis tools. +- [Modernizer](https://github.com/gaul/modernizer-maven-plugin) - Detect uses of legacy Java APIs. +- [Mutability Detector](https://github.com/MutabilityDetector/MutabilityDetector) - Reports whether instances of a given class are immutable. +- [NullAway](https://github.com/uber/NullAway) - Eliminates NullPointerExceptions with low build-time overhead. +- [OpenRewrite](https://github.com/openrewrite/rewrite) - Automates large-scale source-code refactoring through reusable recipes. +- [OpenTaint](https://github.com/seqra/opentaint) - Interprocedural taint analyzer for Java and Spring applications with reusable security rules and dependency models. +- [PMD](https://github.com/pmd/pmd) - Source code analysis for finding bad coding practices. +- [RefactorFirst](https://github.com/jimbethancourt/RefactorFirst) - Identifies and prioritizes God Classes and Highly Coupled classes. +- [SonarJava](https://github.com/SonarSource/sonar-java) - Static analyzer for SonarQube & SonarLint. (LGPL-3.0-only) +- [Spoon](https://github.com/INRIA/spoon) - Library for analyzing and transforming Java source code. +- [Spotbugs](https://github.com/spotbugs/spotbugs) - Static analysis of bytecode to find potential bugs. +- [ToolsHref](https://github.com/toolshref-tools/toolshref-tools) - Online Java code analyzer and JSON-to-Mermaid visualization tool. + +### Code Coverage + +_Frameworks and tools that enable code coverage metrics collection for test suites._ + +- [OpenClover](https://github.com/openclover/clover) - Measures Java code coverage through source-code instrumentation, with build-tool and IDE integrations. +- [Delta Coverage](https://github.com/gw-kit/delta-coverage-plugin) - Computes code coverage of new and modified code based on a provided diff, supporting JaCoCo and IntelliJ coverage engines. +- [JaCoCo](https://github.com/jacoco/jacoco) - Framework that enables collection of code coverage metrics, using both offline and runtime bytecode instrumentation. + +### Code Formatting + +_Tools that format or restructure Java source code._ + +- [google-java-format](https://github.com/google/google-java-format) - Reformats Java source code to follow Google Java Style. +- [JHarmonizer](https://github.com/lemon-ant/JHarmonizer) - Safely reorders Java source code with configurable rules and Palantir Java Format. +- [Palantir Java Format](https://github.com/palantir/palantir-java-format) - Formatter based on google-java-format with wider lines and lambda-friendly output. +- [Spotless](https://github.com/diffplug/spotless) - A versatile code formatter for Gradle and Maven that enforces multiple styles (including Google and Palantir) across Java and other languages. + +### Code Generators + +_Tools that generate patterns for repetitive code in order to reduce verbosity and error-proneness._ + +- [Auto](https://github.com/google/auto) - Generates factory, service, and value classes. +- [Avaje HTTP](https://github.com/avaje/avaje-http) - Generates HTTP server adapters and declarative clients, with a lightweight JDK HTTP client. +- [Bootify](https://bootify.io) - Browser-based Spring Boot app generation with JPA model and REST API. +- [Chocotea](https://github.com/cleopatra27/chocotea) - Generates postman collection, environment and integration tests from java code. +- [CRUDGen](https://github.com/bariskokulu/CRUDGen) - Compile-time annotation processor generating CRUD layers, DTOs, JSON Patch, and custom HTTP endpoints for Spring Boot. +- [EasyEntityToDTO](https://github.com/Marcel091004/EasyEntityToDTO) - Annotation processor for automatic DTO and Mapper generation with zero boilerplate. +- [Geci](https://github.com/verhas/javageci) - Discovers files that need generated code, updates automatically and writes to the source with a convenient API. +- [Immutables](https://github.com/immutables/immutables) - Annotation processors to generate simple, safe and consistent value objects. +- [J2ObjC](https://github.com/google/j2objc) - Java-to-Objective-C translator for porting Android libraries to iOS. +- [JHipster](https://github.com/jhipster/generator-jhipster) - Yeoman source code generator for Spring Boot and AngularJS. +- [Joda-Beans](https://github.com/JodaOrg/joda-beans) - Small framework that adds queryable properties to Java, enhancing JavaBeans. +- [jsonschema2pojo](https://github.com/joelittlejohn/jsonschema2pojo) - Generates Java types from JSON Schema or example JSON. +- [JPA Buddy](https://www.jpa-buddy.com) - Plugin for IntelliJ IDEA. Provides visual tools for generating JPA entities, Spring Data JPA repositories, Liquibase changelogs and SQL scripts. Offers automatic Liquibase/Flyway script generation by comparing model to DB, and reverse engineering JPA entities from DB tables. +- [JSpecify Package-Info Generator](https://github.com/bcaillard/jspecify-packageinfo-generator) - Maven plugin that automatically generates package-info.java files with JSpecify annotations (@NullMarked and @NullUnmarked), helping you manage nullness boundaries in your Java projects without manual boilerplate. +- [Lombok](https://github.com/projectlombok/lombok) - Code generator that aims to reduce verbosity. +- [Record-Builder](https://github.com/Randgalt/record-builder) - Companion builder class, withers and templates for Java records. +- [Spring CRUD Generator](https://github.com/mzivkovicdev/spring-crud-generator) - Maven plugin for generating Spring Boot CRUD applications from YAML/JSON specifications. +- [Telosys](https://www.telosys.org/) - Java code-generation toolkit with a CLI and model-driven template engine. + +### Compiler-compiler + +_Frameworks that help to create parsers, interpreters or compilers._ + +- [ANTLR](https://github.com/antlr/antlr4) - Complex full-featured framework for top-down parsing. +- [JavaCC](https://github.com/javacc/javacc) - Parser generator that generates top-down parsers. Allows lexical state switching and permits extended BNF specifications. +- [JFlex](https://github.com/jflex-de/jflex) - Lexical analyzer generator. + +### Computer Vision + +_Libraries which seek to gain high level information from images and videos._ + +- [BoofCV](https://github.com/lessthanoptimal/BoofCV) - Library for image processing, camera calibration, tracking, SFM, MVS, 3D vision, QR Code and much more. +- [ImageJ](https://github.com/imagej/ImageJ) - Medical image processing application with an API. +- [JavaCV](https://github.com/bytedeco/javacv) - Java interface to OpenCV, FFmpeg, and much more. + +### Configuration + +_Libraries that provide external configuration._ + +- [avaje config](https://github.com/avaje/avaje-config) - Loads yaml and properties files, supports dynamic configuration, plugins, file-watching and config event listeners. +- [centraldogma](https://github.com/line/centraldogma) - Highly-available version-controlled service configuration repository based on Git, ZooKeeper and HTTP/2. +- [ClearConfig](https://github.com/japgolly/clear-config-java) - Type-safe, composable configuration library with a focus on runtime clarity. +- [config](https://github.com/lightbend/config) - Configuration library supporting Java properties, JSON or its human optimized superset HOCON. +- [Configurate](https://github.com/SpongePowered/Configurate) - Configuration library with support for various configuration formats and transformations. +- [dotenv](https://github.com/shyiko/dotenv) - Twelve-factor configuration library which uses environment-specific files. +- [Externalized Properties](https://github.com/joel-jeremy/externalized-properties) - Simple, lightweight, yet powerful configuration library which supports resolution of properties from external sources such as files, databases, git repositories, and any custom sources, plus an extensible post-processing/conversion mechanism. +- [Gestalt](https://github.com/gestalt-config/gestalt) - Gestalt offers a comprehensive solution to the challenges of configuration management. It allows you to source configuration data from multiple inputs, merge them intelligently, and present them in a structured, type-safe manner. +- [ini4j](https://ini4j.sourceforge.net) - Provides an API for handling Windows' INI files. +- [KAConf](https://github.com/mariomac/kaconf) - Annotation-based configuration system for Java and Kotlin. +- [microconfig](https://github.com/microconfig/microconfig) - Configuration system designed for microservices which helps to separate configuration from code. The configuration for different services can have common and specific parts and can be dynamically distributed. +- [NightConfig](https://github.com/TheElectronWill/night-config) - Configuration library supporting TOML, YAML, HOCON, JSON and in-memory formats. +- [owner](https://github.com/matteobaccan/owner) - Reduces boilerplate of properties. +- [sealed-env](https://github.com/davidalmeidac/sealed-env) - Encrypts environment files with a shared Node.js and Java/Spring Boot format plus optional TOTP unsealing. + +### Constraint Satisfaction Problem Solver + +_Libraries that help with implementing optimization and satisfiability problems._ + +- [Choco](https://github.com/chocoteam/choco-solver) - Off-the-shelf constraint satisfaction problem solver that uses constraint programming techniques. +- [JaCoP](https://github.com/radsz/jacop) - Includes an interface for the FlatZinc language, enabling it to execute MiniZinc models. (AGPL-3.0) +- [Timefold](https://github.com/TimefoldAI/timefold-solver) - Flexible solver with Spring/Quarkus support and quickstarts for the Vehicle Routing Problem, Maintenance Scheduling, Employee Shift Scheduling and much more. + +### CSV + +_Frameworks and libraries that simplify reading/writing CSV data._ + +- [FastCSV](https://github.com/osiegmar/FastCSV) - Performance-optimized, dependency-free and RFC 4180 compliant. +- [jackson-dataformat-csv](https://github.com/FasterXML/jackson-dataformats-text) - Jackson extension for reading and writing CSV. +- [opencsv](https://opencsv.sourceforge.net) - Simple CSV parser. + +### Data Processing + +_Tools for batch, stream, table and data-transformation workloads._ + +- [Apache Flink](https://github.com/apache/flink) - Fast, reliable, large-scale data processing engine. +- [Apache Storm](https://github.com/apache/storm) - Realtime computation system. +- [easy-batch](https://github.com/j-easy/easy-batch) - Set up batch jobs with simple processing pipelines. Records are read in sequence from a data source, processed in pipeline and written in batches to a data sink. +- [Embulk](https://github.com/embulk/embulk) - Bulk data loader that helps data transfer between various databases, storages, file formats, and cloud services. +- [OpenRefine](https://github.com/OpenRefine/OpenRefine) - Tool for working with messy data: cleaning, transforming, extending it with web services and linking it to databases. +- [Siddhi](https://github.com/siddhi-io/siddhi) - Cloud native streaming and complex event processing engine. +- [Smooks](https://github.com/smooks/smooks) - Framework for fragment-based message processing. (Apache-2.0 OR LGPL-3.0-or-later) +- [Tablesaw](https://github.com/jtablesaw/tablesaw) - Includes a data-frame, an embedded column store, and hundreds of methods to transform, summarize, or filter data. + +### Data Structures + +_Efficient and specific data structures._ + +- [CQEngine Next](https://github.com/MSaifAsif/cqengine-next) - Provides indexed, SQL-like queries over Java collections. +- [HashSmith](https://github.com/bluuewhale/hash-smith) - Hash map and set implementations using SwissTable-style SWAR/SIMD control-byte probing, optimized for memory efficiency. +- [Persistent Collection](https://github.com/hrldcpr/pcollections) - Persistent and immutable analogue of the Java Collections Framework. +- [RoaringBitmap](https://github.com/RoaringBitmap/RoaringBitmap) - Fast and efficient compressed bitmap. +- [Wormhole4j](https://github.com/komamitsu/wormhole4j) - High-performance sorted map with fast range scans and thread-safe concurrent access, based on the Wormhole index structure. + +### Database + +_Everything that simplifies interactions with the database._ + +- [Actual Schema Gradle Plugin](https://github.com/YRashid/actual-schema-gradle-plugin) - Generates PostgreSQL schema DDL from Liquibase migrations using Testcontainers. +- [Apache Calcite](https://github.com/apache/calcite) - Dynamic data management framework. It contains many of the pieces that comprise a typical database management system. +- [Apache Cassandra](https://github.com/apache/cassandra) - Distributed wide-column database with linear scalability and fault tolerance. +- [Apache Doris](https://github.com/apache/doris) - Distributed SQL database for real-time analytics. +- [Apache Drill](https://github.com/apache/drill) - Distributed, schema on-the-fly, ANSI SQL query engine for Big Data exploration. +- [Apache Phoenix](https://github.com/apache/phoenix) - High-performance relational database layer over HBase for low-latency applications. +- [ArcadeDB](https://github.com/ArcadeData/arcadedb) - Multi-model database supporting graphs, documents, key-value, time series, and vector embeddings with SQL, Cypher, Gremlin, MongoDB, and Redis API compatibility. +- [ArangoDB](https://github.com/arangodb/arangodb-java-driver) - ArangoDB Java driver. +- [Chronicle Map](https://github.com/OpenHFT/Chronicle-Map) - Efficient, in-memory (opt. persisted to disk), off-heap key-value store. +- [ClickHouse Java](https://github.com/ClickHouse/clickhouse-java) - Java clients and JDBC driver for ClickHouse. +- [Debezium](https://github.com/debezium/debezium) - Low latency data streaming platform for change data capture. +- [druid](https://github.com/apache/druid) - High-performance, column-oriented, distributed data store. +- [eXist](https://github.com/eXist-db/exist) - NoSQL document database and application platform. +- [FlexyPool](https://github.com/vladmihalcea/flexy-pool) - Brings metrics and failover strategies to the most common connection pooling solutions. +- [Flyway](https://github.com/flyway/flyway) - Simple database migration tool. +- [H2](https://github.com/h2database/h2database) - Small SQL database notable for its in-memory functionality. +- [HikariCP](https://github.com/brettwooldridge/HikariCP) - High-performance JDBC connection pool. +- [HSQLDB](https://hsqldb.org/) - HyperSQL 100% Java database. +- [JanusGraph](https://github.com/JanusGraph/janusgraph) - Distributed graph database supporting pluggable storage and indexing backends. +- [JDBI](https://github.com/jdbi/jdbi) - Convenient abstraction of JDBC. +- [Jedis](https://github.com/redis/jedis) - Java client for Redis with synchronous, asynchronous and cluster APIs. +- [jetcd](https://github.com/etcd-io/jetcd) - Java client for etcd v3. +- [Jinq](https://github.com/my2iu/Jinq) - Typesafe database queries via symbolic execution of Java 8 Lambdas (on top of JPA or jOOQ). +- [jOOQ](https://github.com/jOOQ/jOOQ) - Generates typesafe code based on SQL schema. +- [Lettuce](https://github.com/redis/lettuce) - Lettuce is a scalable Redis client for building non-blocking Reactive applications. +- [Liquibase](https://github.com/liquibase/liquibase) - Database-independent library for tracking, managing and applying database schema changes. +- [MapDB](https://github.com/jankotek/mapdb) - Embedded database engine that provides concurrent collections backed on disk or in off-heap memory. +- [MariaDB4j](https://github.com/vorburger/MariaDB4j) - Launcher for MariaDB that requires no installation or external dependencies. +- [Modality](https://github.com/arkanovicz/modality) - Lightweight ORM with database reverse engineering features. +- [MongoDB Java Driver](https://github.com/mongodb/mongo-java-driver) - Official synchronous, asynchronous and reactive Java drivers for MongoDB. +- [ObjectBox](https://github.com/objectbox/objectbox-java) - Embedded object and vector database for Java and Android. +- [Open J Proxy](https://github.com/Open-J-Proxy/ojp) - Type 3 JDBC driver and Layer 7 proxy server for decoupling applications from relational database connection management. +- [OpenDJ](https://github.com/OpenIdentityPlatform/OpenDJ) - LDAPv3 compliant directory service, developed for the Java platform, providing a high performance, highly available, and secure store for the identities. +- [Querydsl](https://github.com/querydsl/querydsl) - Typesafe unified queries. +- [QueryStream](https://github.com/querystream/querystream) - Build JPA Criteria queries using a Stream-like API. +- [Presto](https://github.com/prestodb/presto) - Distributed SQL query engine for large data sources. +- [QuestDB](https://github.com/questdb/questdb) - High-performance SQL database for time series. Supports InfluxDB line protocol, PostgreSQL wire protocol, and REST. +- [Realm](https://github.com/realm/realm-java) - Mobile database to run directly inside phones, tablets or wearables. +- [Redisson](https://github.com/redisson/redisson) - Allows for distributed and scalable data structures on top of a Redis server. +- [requery](https://github.com/requery/requery) - Modern, lightweight but powerful object mapping and SQL generator. Easily map to or create databases, or perform queries and updates from any Java-using platform. +- [SchemaCrawler](https://github.com/schemacrawler/SchemaCrawler) - Discovers, documents and diagrams relational database schemas from Java, build tools and the command line. +- [Spring Data Dynamic Query](https://github.com/tdilber/spring-data-dynamic-query) - Unified dynamic query interface for Spring Data JPA, MongoDB, and Elasticsearch, enabling advanced JOIN(s), OR logic, scoped conditions, powerful projections and advanced features with zero boilerplate. +- [Spring Data JPA MongoDB Expressions](https://github.com/mhewedy/spring-data-jpa-mongodb-expressions) - Allows you to use MongoDB query language to query your relational database. +- [StarRocks](https://github.com/StarRocks/starrocks) - Distributed SQL query engine for real-time analytics and data lakehouses. +- [Trino](https://github.com/trinodb/trino) - Distributed SQL query engine for big data. +- [Vibur DBCP](https://github.com/vibur/vibur-dbcp) - JDBC connection pool library with advanced performance monitoring capabilities. +- [Xodus](https://github.com/JetBrains/xodus) - Highly concurrent transactional schema-less and ACID-compliant embedded database. +- [CosId](https://github.com/Ahoo-Wang/CosId) - Universal, flexible, high-performance distributed ID generator. +- [Apache ShardingSphere](https://github.com/apache/shardingsphere) - Distributed SQL transaction & query engine that allows for data sharding, scaling, encryption, and more on any database. + +### Date and Time + +_Libraries related to handling date and time._ + +- [iCal4j](https://github.com/ical4j/ical4j) - Parse and build iCalendar [RFC 5545](https://tools.ietf.org/html/rfc5545) data models. +- [Jollyday](https://github.com/focus-shift/jollyday) - Determines the holidays for a given year, country/name and eventually state/region. +- [ThreeTen-Extra](https://github.com/ThreeTen/threeten-extra) - Additional date-time classes that complement those in JDK 8. +- [Time4J](https://github.com/MenoData/Time4J) - Advanced date and time library. + +### Decentralization + +_Libraries that handle decentralization tasks._ + +- [java-tron](https://github.com/tronprotocol/java-tron) - Implementation of the Tron Protocol, whic utilizes blockchains to develop decentralized applications. +- [bitcoinj](https://github.com/bitcoinj/bitcoinj) - Library for working with the Bitcoin protocol and network. +- [web3j](https://github.com/LFDT-web3j/web3j) - Java and Android library for integrating with Ethereum-compatible blockchains. + +### Decompilation + +_Libraries for decompiling JVM bytecode._ + +- [CFR](https://github.com/leibnitz27/cfr) - Java decompiler focused on modern language features. +- [Fernflower](https://github.com/JetBrains/fernflower) - Java decompiler with broad JVM bytecode support. +- [jadx](https://github.com/skylot/jadx) - Dex-to-Java decompiler with command-line and graphical interfaces. +- [transformer-api](https://github.com/nbauma109/transformer-api) - Unified API that exposes multiple decompilers through one in-memory transformation interface. +- [Vineflower](https://github.com/Vineflower/vineflower) - Modern maintained fork of Fernflower. + +### Dependency Injection + +_Libraries that help to realize the [Inversion of Control](https://en.wikipedia.org/wiki/Inversion_of_control) paradigm._ + +- [Apache DeltaSpike](https://github.com/apache/deltaspike) - CDI extension framework. +- [Avaje Inject](https://github.com/avaje/avaje-inject) - Microservice-focused compile-time injection framework without reflection. +- [Dagger](https://github.com/google/dagger) - Compile-time injection framework without reflection. +- [Dimension-DI](https://github.com/akardapolov/dimension-di) - JSR-330 runtime dependency injection using the JDK Class-File API. +- [Governator](https://github.com/Netflix/governator) - Extensions and utilities that enhance Google Guice. +- [Guice](https://github.com/google/guice) - Lightweight and opinionated framework that completes Dagger. +- [HK2](https://github.com/eclipse-ee4j/glassfish-hk2) - Lightweight and dynamic dependency injection framework. + +### Development + +_Augmentation of the development process at a fundamental level._ + +- [AspectJ](https://github.com/eclipse-aspectj/aspectj) - Seamless aspect-oriented programming extension. +- [Faux Pas](https://github.com/zalando/faux-pas) - Library that simplifies error handling by circumventing the issue that none of the functional interfaces in the Java Runtime is allowed by default to throw checked exceptions. +- [Ghidra](https://github.com/NationalSecurityAgency/ghidra) - Extensible software reverse-engineering framework with Java APIs and scripting. +- [HotswapAgent](https://github.com/HotswapProjects/HotswapAgent) - Unlimited runtime class and resource redefinition. +- [Jctx](https://github.com/Shashwat-Gupta57/jctx) - Reads a Java project and generates a structured context file so AI tools can understand and help plan the codebase. +- [JGit](https://github.com/eclipse-jgit/jgit) - Lightweight, pure Java library implementing the Git version control system. +- [JavaParser](https://github.com/javaparser/javaparser) - Parse, modify and generate Java code. +- [Manifold](https://github.com/manifold-systems/manifold) - Re-energizes Java with powerful features like type-safe metaprogramming, structural typing and extension methods. +- [NoException](https://github.com/robertvazan/noexception) - Allows checked exceptions in functional interfaces and converts exceptions to Optional return. +- [RR4J](https://github.com/Kartikvk1996/RR4J) - RR4J is a tool that records java bytecode execution and later allows developers to replay locally. +- [SneakyThrow](https://github.com/rainerhahnekamp/sneakythrow) - Ignores checked exceptions without bytecode manipulation. Can also be used inside Java 8 stream operations. +- [Tail](https://github.com/nrktkt/tail) - Enable infinite recursion using tail call optimization. + +### Distributed Applications + +_Libraries and frameworks for writing distributed and fault-tolerant applications._ + +- [Apache Geode](https://github.com/apache/geode) - In-memory data management system that provides reliable asynchronous event notifications and guaranteed message delivery. +- [Apache ZooKeeper](https://github.com/apache/zookeeper) - Coordination service with distributed configuration, synchronization, and naming registry for large distributed systems. +- [Axon](https://github.com/AxonIQ/AxonFramework) - Framework for creating CQRS applications. +- [Curator Framework](https://github.com/apache/curator) - High-level API for Apache ZooKeeper. +- [Dropwizard Circuit Breaker](https://github.com/mtakaki/dropwizard-circuitbreaker) - Circuit breaker design pattern for Dropwizard. +- [Failsafe](https://github.com/failsafe-lib/failsafe) - Simple failure handling with retries and circuit breakers. +- [Hazelcast](https://github.com/hazelcast/hazelcast) - Highly scalable in-memory datagrid with a free open-source version. +- [JGroups](https://github.com/belaban/JGroups) - Toolkit for reliable messaging and cluster creation. +- [resilience4j](https://github.com/resilience4j/resilience4j) - Functional fault tolerance library. +- [ScaleCube Services](https://github.com/scalecube/scalecube-services) - Embeddable Cluster-Membership library based on SWIM and gossip protocol. + +### Distributed Transactions + +_Distributed transactions provide a mechanism for ensuring consistency of data updates in the presence of concurrent access and partial failures._ + +- [Atomikos](https://github.com/atomikos/transactions-essentials) - Provides transactions for REST, SOA and microservices with support for JTA and XA. +- [Bitronix](https://github.com/bitronix/btm) - Simple but complete implementation of the JTA 1.1 API. +- [Narayana](https://github.com/jbosstm/narayana) - Provides support for traditional ACID and compensation transactions, also complies with JTA, JTS and other standards. +- [Seata](https://github.com/apache/incubator-seata) - Delivers high performance and easy to use distributed transaction services under a microservices architecture. + +### Distribution + +_Tools that handle the distribution of applications in native formats._ + +- [Artipie](https://github.com/artipie/artipie) - Binary artifact management toolkit which hosts them on the file system or S3. +- [Boxfuse](https://boxfuse.com) - Deployment of JVM applications to AWS using the principles of immutable infrastructure. +- [Central Repository](https://search.maven.org) - Largest binary component repository available as a free service to the open-source community. Default used by Apache Maven, and available in all other build tools. +- [Cloudsmith](https://cloudsmith.io) - Fully managed package management SaaS with support for Maven/Gradle/SBT with a free tier. +- [Getdown](https://github.com/threerings/getdown) - System for deploying Java applications to end-user computers and keeping them up to date. Developed as an alternative to Java Web Start. +- [IzPack](https://github.com/izpack/izpack) - Setup authoring tool for cross-platform deployments. +- [JavaPackager](https://github.com/javapackager/JavaPackager) - Maven and Gradle plugin which provides an easy way to package Java applications in native Windows, macOS or GNU/Linux executables, and generate installers for them. +- [jDeploy](https://github.com/shannah/jdeploy) - Deploy desktop apps as native Mac, Windows or Linux bundles. +- [jlink.online](https://github.com/AdoptOpenJDK/jlink.online) - Builds optimized runtimes over HTTP. +- [Nuts](https://github.com/thevpc/nuts) - Installs and runs Java applications from Maven repositories, reusing descriptors and provisioning required JDKs. +- [Nexus](https://github.com/sonatype/nexus-public) - Binary management with proxy and caching capabilities. +- [packr](https://github.com/libgdx/packr) - Packs JARs, assets and the JVM for native distribution on Windows, Linux and macOS. +- [really-executable-jars-maven-plugin](https://github.com/brianm/really-executable-jars-maven-plugin) - Maven plugin for making self-executing JARs. + +### Document Processing + +_Libraries that assist with processing office document formats._ + +- [Apache Tika](https://github.com/apache/tika) - Detects and extracts text and metadata from a wide range of document formats. +- [commonmark-java](https://github.com/commonmark/commonmark-java) - Parses and renders CommonMark-compatible Markdown. +- [documents4j](https://github.com/documents4j/documents4j) - API for document format conversion using third-party converters such as MS Word. +- [docx4j](https://github.com/plutext/docx4j) - Create and manipulate Microsoft Open XML files. +- [html-to-markdown](https://github.com/xberg-io/html-to-markdown) - Converts HTML to CommonMark-compatible Markdown through a Java binding. +- [JQuick Excel](https://github.com/paohaijiao/jquick-excel) - Configures Excel import, export, validation, formulas and charts through a declarative XML DSL. +- [xberg](https://github.com/xberg-io/xberg) - Extracts text, tables and metadata from PDFs, Office documents, images and other formats through a Java binding. + +### Feature Flags + +_Libraries and SDKs for evaluating and managing feature flags._ + +- [FF4J](https://github.com/ff4j/ff4j) - Feature Flags for Java. +- [OpenFeature Java SDK](https://github.com/open-feature/java-sdk) - Vendor-neutral API for evaluating feature flags in Java applications. +- [Rollgate Java SDK](https://github.com/rollgate/sdks/tree/main/packages/sdk-java) - Java SDK for evaluating Rollgate feature flags with real-time configuration updates. +- [Togglz](https://github.com/togglz/togglz) - Implementation of the Feature Toggles pattern. +- [Unleash Java SDK](https://github.com/Unleash/unleash-java-sdk) - Java client SDK for the Unleash feature management platform. + +### Financial + +_Libraries related to the financial domain._ + +- [Cassandre](https://github.com/cassandre-tech/cassandre-trading-bot) - Trading bot framework. +- [Joda-Money](https://github.com/JodaOrg/joda-money) - Basic currency and money classes and algorithms not provided by the JDK. +- [OpenGamma Strata](https://github.com/OpenGamma/Strata) - Analytics and market risk library for financial products. +- [Philadelphia](https://github.com/paritytrading/philadelphia) - Low-latency financial information exchange. +- [Stripe](https://github.com/stripe/stripe-java) - Integration with the Stripe API. +- [ta4j](https://github.com/ta4j/ta4j) - Library for technical analysis. +- [XChange](https://github.com/knowm/XChange) - Consistent Java API for market data and trading across cryptocurrency exchanges. +- [Wickra](https://github.com/wickra-lib/wickra) - Technical-analysis library with 514 streaming O(1)-per-tick indicators on a native Rust core, on Maven Central as org.wickra:wickra; more indicators and incremental updates than the pure-Java ta4j. + +### Flat File + +_Frameworks and libraries for reading and writing fixed-length and delimited flat files._ + +- [BeanIO](https://github.com/beanio/beanio) - Maps flat files of fixed-length or delimited records to and from Java beans using XML or annotation configuration. +- [fixedformat4j](https://github.com/jeyben/fixedformat4j) - Annotation-driven mapping of fixed-width flat files to and from POJOs and Java records. +- [Flatpack](https://github.com/Appendium/flatpack) - Parses and writes delimited and fixed-length flat files with optional column-mapping definitions. + +### Formal Verification + +_Formal-methods tools: proof assistants, model checking, symbolic execution, etc._ + +- [Checker Framework](https://github.com/typetools/checker-framework) - Pluggable type systems. Includes nullness types, physical units, immutability types and more. (GPL-2.0-only WITH Classpath-exception-2.0) +- [Daikon](https://github.com/codespecs/daikon) - Detects likely program invariants and generates JML specs based on those invariants. +- [Java Path Finder (JPF)](https://github.com/javapathfinder/jpf-core) - JVM formal verification tool containing a model checker and more. Created by NASA. +- [JMLOK 2.0](https://massoni.computacao.ufcg.edu.br/home/jmlok) - Detects inconsistencies between code and JML specification through feedback-directed random tests generation, and suggests a likely cause for each nonconformance detected. (GPL-3.0-only) +- [KeY](https://github.com/KeYProject/key) - Formal software development tool that aims to integrate design, implementation, formal specification, and formal verification of object-oriented software as seamlessly as possible. Uses JML for specification and symbolic execution for verification. (GPL-2.0-or-later) +- [OpenJML](https://github.com/OpenJML/OpenJML) - Translates JML specifications into SMT-LIB format and passes the proof problems implied by the program to backend solvers. (GPL-2.0-only) + +### Functional Programming + +_Libraries that facilitate functional programming._ + +- [Fugue](https://bitbucket.org/atlassian/fugue) - Functional extensions to Guava. +- [Functional Java](https://github.com/functionaljava/functionaljava) - Implements numerous basic and advanced programming abstractions that assist composition-oriented development. +- [jOOΞ»](https://github.com/jOOQ/jOOL) - Extension to Java 8 that aims to fix gaps in lambda by providing numerous missing types and a rich set of sequential Stream API additions. +- [Packrat](https://github.com/jhspetersson/packrat) - Gatherers library for Java Stream API. Gatherers can enhance streams with custom intermediate operations. +- [Parallel Collectors](https://github.com/pivovarit/parallel-collectors) - Stream API Collectors for parallel processing with custom thread pools, designed for I/O-heavy workloads. +- [protonpack](https://github.com/poetix/protonpack) - Collection of stream utilities. +- [StreamEx](https://github.com/amaembo/streamex) - Enhances Java 8 Streams. +- [Vavr](https://github.com/vavr-io/vavr) - Functional component library that provides persistent data types and functional control structures. + +### Game Development + +_Frameworks that support the development of games._ + +- [FXGL](https://github.com/AlmasB/FXGL) - JavaFX Game Development Framework. +- [input4j](https://github.com/gurkenlabs/input4j) - Lightweight, cross-platform library for gamepad and joystick input handling. +- [JBox2D](https://github.com/jbox2d/jbox2d) - Port of the renowned C++ 2D physics engine. +- [jMonkeyEngine](https://github.com/jMonkeyEngine/jmonkeyengine) - Game engine for modern 3D development. +- [libGDX](https://github.com/libgdx/libgdx) - All-round cross-platform, high-level framework. +- [Litiengine](https://github.com/gurkenlabs/litiengine) - AWT-based, lightweight 2D game engine. +- [LWJGL](https://github.com/LWJGL/lwjgl3) - Robust framework that abstracts libraries like OpenGL/CL/AL. +- [Pathetic](https://github.com/bsommerfeld/pathetic) - A highly configurable 3D A\* pathfinding library that uses specific optimizations for high performance. +- [vulkan4j](https://github.com/chuigda/vulkan4j) - Vulkan, OpenGL ES2 and GLFW Memory Allocator bindings. + +### Geospatial + +_Libraries for working with geospatial data and algorithms._ + +- [Apache SIS](https://github.com/apache/sis) - Library for developing geospatial applications. +- [ArcGIS Maps SDK for Java](https://github.com/Esri/arcgis-maps-sdk-java-samples/) - JavaFX library for adding mapping and GIS functionality to desktop apps. +- [Geo](https://github.com/davidmoten/geo) - GeoHash utilities in Java. +- [GeoTools](https://github.com/geotools/geotools) - Library that provides tools for geospatial data. +- [GraphHopper](https://github.com/graphhopper/graphhopper) - Road-routing engine. Used as a Java library or standalone web service. +- [H2GIS](https://github.com/orbisgis/h2gis) - Spatial extension of the H2 database. +- [IP2Location.io Java SDK](https://github.com/ip2location/ip2location-io-java) - Wrapper for the IP2Location.io Geolocation API and the IP2WHOIS domain WHOIS API. +- [JTS](https://github.com/locationtech/jts) - Geometry model and algorithms for manipulating vector geospatial data. +- [Jgeohash](https://github.com/astrapi69/jgeohash) - Library for using the GeoHash algorithm. +- [Mapsforge](https://github.com/mapsforge/mapsforge) - Map rendering based on OpenStreetMap data. +- [Open Location Code](https://github.com/google/open-location-code) - Encodes geographic coordinates as short, shareable Plus Codes. +- [Spatial4j](https://github.com/locationtech/spatial4j) - General-purpose spatial/geospatial library. + +### GUI + +_Libraries to create modern graphical user interfaces._ + +- [FlatLaf](https://github.com/JFormDesigner/FlatLaf) - Modern Swing Look and Feel with Darcula and IntelliJ themes. +- [ControlsFX](https://github.com/controlsfx/controlsfx) - UI controls and components that complement JavaFX. +- [JavaFX](https://github.com/openjdk/jfx) - Successor of Swing. +- [Scene Builder](https://github.com/gluonhq/scenebuilder) - Visual layout tool for JavaFX applications. +- [SnapKit](https://github.com/reportmill/SnapKit) - Modern Java UI library for both desktop and web. +- [Sierra](https://github.com/HTTP-RPC/Sierra) - Lightwieght declarative DSL for rapid development of Swing applications. +- [SWT](https://github.com/eclipse-platform/eclipse.platform.swt) - Graphical widget toolkit. + +### High Performance + +_Everything about high-performance computation, from collections to specific libraries._ + +- [Agrona](https://github.com/aeron-io/agrona) - Data structures and utility methods that are common in high-performance applications. +- [Disruptor](https://github.com/LMAX-Exchange/disruptor) - Inter-thread messaging library. +- [Eclipse Collections](https://github.com/eclipse-collections/eclipse-collections) - Collections framework inspired by Smalltalk. +- [fastutil](https://github.com/vigna/fastutil) - Fast and compact type-specific collections. +- [HPPC](https://github.com/carrotsearch/hppc) - Primitive collections. +- [Hollow](https://github.com/Netflix/hollow) - High-performance in-memory datasets distributed from a single producer to many consumers. +- [JCTools](https://github.com/JCTools/JCTools) - Concurrency tools currently missing from the JDK. +- [TransmittableThreadLocal](https://github.com/alibaba/transmittable-thread-local) - Propagates thread-local context across thread pools and asynchronous execution. + +### HTTP Clients + +_Libraries that assist with creating HTTP requests and/or binding responses._ + +- [Apache HttpComponents](https://hc.apache.org/) - Toolset of low-level Java components focused on HTTP and related protocols. +- [Async Http Client](https://github.com/AsyncHttpClient/async-http-client) - Asynchronous HTTP and WebSocket client library. +- [Feign](https://github.com/OpenFeign/feign) - HTTP client binder inspired by Retrofit, JAXRS-2.0, and WebSocket. +- [Google HTTP Client](https://github.com/googleapis/google-http-java-client) - Pluggable HTTP transport abstraction with support for java.net.HttpURLConnection, Apache HTTP Client, Android, Google App Engine, XML, Gson, Jackson and Protobuf. +- [methanol](https://github.com/mizosoft/methanol) - HTTP client extensions library. +- [OkHttp](https://github.com/lysine-dev/okhttp) - HTTP client for the JVM, Android and GraalVM. +- [Retrofit](https://github.com/lysine-dev/retrofit) - Typesafe REST client. +- [Ribbon](https://github.com/Netflix/ribbon) - Client-side IPC library that is battle-tested in the cloud. +- [Riptide](https://github.com/zalando/riptide) - Client-side response routing for Spring's RestTemplate. +- [unirest-java](https://github.com/Kong/unirest-java) - Simplified, lightweight HTTP client library. +- [JQuickCurl](https://github.com/paohaijiao-jquick/jquick-curl) - Executes HTTP requests from cURL syntax through annotations, XML configuration and dynamic proxy clients. + +### IDE + +_Integrated development environments that try to simplify several aspects of development._ + +- [Eclipse Java IDE](https://www.eclipse.org) - Extensible Java IDE assembled from the Eclipse Platform, JDT and PDE. +- [Explyt](https://github.com/explyt/explyt) - AI coding agent for JetBrains IDEs that uses IDE indexes, refactorings, test runners, static analysis and debugging for Java and Kotlin projects. +- [IntelliJ IDEA](https://github.com/JetBrains/intellij-community) - Supports many JVM languages and provides good options for Android development. The commercial edition targets the enterprise sector. +- [jGRASP](https://www.jgrasp.org) - Created to provide software visualizations that work in conjunction with the debugger such as Control Structure Diagrams, UML class diagrams and Object Viewer. +- [NetBeans](https://github.com/apache/netbeans) - Provides integration for several Java SE and EE features, from database access to HTML5. +- [SnapCode](https://github.com/reportmill/SnapCode) - Modern IDE for Java running in the browser, focused on education. +- [Visual Studio Code Java](https://code.visualstudio.com/docs/languages/java) - Extension suite providing Java language support, debugging, testing, Maven, Gradle and project management in Visual Studio Code. + +### Imagery + +_Libraries that assist with the creation, evaluation or manipulation of graphical images._ + +- [Barcode-Lib4J](https://github.com/vws-java/Barcode-Lib4J) - Generates QR Code, DataMatrix, and other 1D/2D barcodes as vector (PDF, EPS, SVG) and raster (PNG, BMP, JPG) images with DPI awareness, high precision, and CMYK color model support. +- [Glide](https://github.com/bumptech/glide) - Image loading and caching library for Android focused on smooth scrolling. +- [Imgscalr](https://github.com/rkalla/imgscalr) - Simple, efficient and hardware-accelerated image-scaling library implemented in pure Java 2D. +- [Tess4J](https://github.com/nguyenq/tess4j) - JNA wrapper for Tesseract OCR API. +- [Thumbnailator](https://github.com/coobird/thumbnailator) - High-quality thumbnail generation library. +- [TwelveMonkeys](https://github.com/haraldk/TwelveMonkeys) - Collection of plugins that extend the number of supported image file formats. +- [ZXing](https://github.com/zxing/zxing) - Multi-format 1D/2D barcode image processing library. +- [image-comparison](https://github.com/romankh3/image-comparison) - Library that compares 2 images with the same sizes and shows the differences visually by drawing rectangles. Some parts of the image can be excluded from the comparison. +- [vips-ffm](https://github.com/lopcode/vips-ffm) - Comprehensive bindings for libvips, using Java's "Foreign Function & Memory" API. +- [webcam-capture](https://github.com/sarxos/webcam-capture) - Library for using built-in and external webcams directly in Java. +- [scrimage](https://github.com/sksamuel/scrimage) - Immutable, functional, and performant JVM library for manipulation of images. + +### Introspection + +_Libraries that help make the Java introspection and reflection API easier and faster to use._ + +- [ClassGraph](https://github.com/classgraph/classgraph) - ClassGraph (formerly FastClasspathScanner) is an uber-fast, ultra-lightweight, parallelized classpath scanner and module scanner for Java, Scala, Kotlin and other JVM languages. +- [jOOR](https://github.com/jOOQ/jOOR) - jOOR stands for jOOR Object Oriented Reflection. It is a simple wrapper for the java.lang.reflect package. +- [Objenesis](https://github.com/easymock/objenesis) - Allows dynamic instantiation without default constructor, e.g. constructors which have required arguments, side effects or throw exceptions. +- [ReflectASM](https://github.com/EsotericSoftware/reflectasm) - ReflectASM is a very small Java library that provides high performance reflection by using code generation. +- [TypeTools](https://github.com/jhalterman/typetools) - Tools for resolving generic types. + +### Job Scheduling + +_Libraries for scheduling background jobs._ + +- [JobRunr](https://github.com/jobrunr/jobrunr) - Job scheduling library which utilizes lambdas for fire-and-forget, delayed and recurring jobs. Guarantees execution by single scheduler instance using optimistic locking. Has features for persistence, minimal dependencies and is embeddable. +- [Quartz](https://github.com/quartz-scheduler/quartz) - Feature-rich, open source job scheduling library that can be integrated within virtually any Java application. +- [Sundial](https://github.com/knowm/Sundial) - Lightweight framework to simply define jobs, define triggers and start the scheduler. +- [Wisp](https://github.com/Coreoz/Wisp) - Simple library with minimal footprint and straightforward API. +- [db-scheduler](https://github.com/kagkarlsson/db-scheduler) - Persistent and cluster-friendly scheduler. +- [shedlock](https://github.com/lukas-krecan/ShedLock) - Makes sure that your scheduled tasks are executed at most once at the same time. If a task is being executed on one node, it acquires a lock which prevents execution of the same task from another node or thread. +- [XXL-JOB](https://github.com/xuxueli/xxl-job) - Distributed task scheduling platform with centralized administration and execution monitoring. + +### JSON + +_Libraries for serializing and deserializing JSON to and from Java objects._ + +- [Avaje Jsonb](https://github.com/avaje/avaje-jsonb) - Reflection-free Json binding via source code generation with Jackson-like annotations. +- [DSL-JSON](https://github.com/ngs-doo/dsl-json) - JSON library with advanced compile time databinding. +- [Fastjson2](https://github.com/alibaba/fastjson2) - High-performance JSON parser, serializer and object mapper. +- [Gson](https://github.com/google/gson) - Serializes objects to JSON and vice versa. Good performance with on-the-fly usage. +- [jackson-modules-java8](https://github.com/FasterXML/jackson-modules-java8) - Set of Jackson modules for Java 8 datatypes and features. +- [Jackson](https://github.com/FasterXML/jackson) - Similar to GSON, but offers performance gains if you need to instantiate the library more often. +- [JSON-io](https://github.com/jdereg/json-io) - Convert Java to JSON/TOON and back. Supports complex object graphs, cyclic references, and TOON format for 40-50% LLM token savings. +- [Moshi](https://github.com/square/moshi) - Modern JSON library, less opinionated and uses built-in types like List and Map. +- [Yasson](https://github.com/eclipse-ee4j/yasson) - Binding layer between classes and JSON documents similar to JAXB. +- [Jolt](https://github.com/bazaarvoice/jolt) - JSON to JSON transformation tool. +- [JsonPath](https://github.com/json-path/JsonPath) - Extract data from JSON using XPATH-like syntax. +- [JsonSurfer](https://github.com/jsurfer/JsonSurfer) - Streaming JsonPath processor dedicated to processing big and complicated JSON data. + +### JVM and JDK + +_Current implementations of the JVM/JDK._ + +- [Eclipse Temurin](https://github.com/adoptium/temurin-build) - OpenJDK distribution from the Eclipse Adoptium project. +- [Corretto](https://aws.amazon.com/corretto/) - No-cost, multiplatform, production-ready distribution of OpenJDK by Amazon. (GPL-2.0-only WITH Classpath-exception-2.0) +- [Dragonwell8](https://github.com/alibaba/dragonwell8) - Downstream version of OpenJDK optimized for online e-commerce, financial, logistics applications. +- [Graal](https://github.com/oracle/graal) - Polyglot embeddable JVM. (GPL-2.0-only WITH Classpath-exception-2.0) +- [Liberica JDK](https://bell-sw.com) - Built from OpenJDK, thoroughly tested and passed the JCK. (GPL-2.0-only WITH Classpath-exception-2.0) +- [OpenJ9](https://github.com/eclipse-openj9/openj9) - High performance, enterprise-calibre, flexibly licensed, openly-governed cross-platform JVM extending and augmenting the runtime technology components from the Eclipse OMR and OpenJDK project. +- [Open JDK](https://github.com/openjdk/jdk) - Open JDK community home. +- [RedHat Open JDK](https://developers.redhat.com/products/openjdk/overview) - RedHat's OpenJDK distribution. (GPL-2.0-only WITH Classpath-exception-2.0) +- [SAP Machine](https://github.com/SAP/SapMachine) - SAP's no-cost, rigorously tested and JCK-verified OpenJDK friendly fork. +- [Zulu](https://www.azul.com/products/zulu-community/) - OpenJDK builds for Windows, Linux, and macOS. (GPL-2.0-only WITH Classpath-exception-2.0) +- [Microsoft JDK](https://github.com/microsoft/openjdk) - Microsoft Build of OpenJDK, Free, Open Source, Freshly Brewed! + +### Logging + +_Libraries that log the behavior of an application._ + +- [Apache Log4j 2](https://github.com/apache/logging-log4j2) - Complete rewrite with a powerful plugin and configuration architecture. +- [Echopraxia](https://github.com/tersesystems/echopraxia) - API designed around structured logging, rich context, and conditional logging. There are Logback and Log4J2 implementations, but Echopraxia's API is completely dependency-free, meaning it can be implemented with any logging API. +- [Graylog](https://github.com/Graylog2/graylog2-server) - Open-source aggregator suited for extended role and permission management. (GPL-3.0-only) +- [Kibana](https://github.com/elastic/kibana) - Analyzes and visualizes log files. Some features require payment. +- [Logback](https://github.com/qos-ch/logback) - Robust logging library with interesting configuration options via Groovy. +- [Logbook](https://github.com/zalando/logbook) - Extensible, open-source library for HTTP request and response logging. +- [Logstash](https://github.com/elastic/logstash) - Tool for managing log files. +- [SLF4J](https://github.com/qos-ch/slf4j) - Abstraction layer/simple logging facade. +- [tinylog](https://github.com/tinylog-org/tinylog) - Lightweight logging framework with static logger class. +- [Flogger](https://github.com/google/flogger) - Flogger is a fluent logging API for Java. It supports a wide variety of features, and has many benefits over existing logging APIs. + +### Machine Learning + +_Tools that provide specific statistical algorithms for learning from data._ + +- [Apache Mahout](https://github.com/apache/mahout) - Scalable algorithms focused on collaborative filtering, clustering and classification. +- [DatumBox](https://github.com/datumbox/datumbox-framework) - Provides several algorithms and pre-trained models for natural language processing. +- [Deeplearning4j](https://github.com/deeplearning4j/deeplearning4j) - Distributed and multi-threaded deep learning library. +- [DJL](https://github.com/deepjavalibrary/djl) - High-level and engine-agnostic framework for deep learning. +- [H2O](https://github.com/h2oai/h2o-3) - Analytics engine for statistics over big data. +- [Intelligent java](https://github.com/Barqawiz/IntelliJava) - Seamlessly integrate with remote deep learning and language models programmatically. +- [JSAT](https://github.com/EdwardRaff/JSAT) - Algorithms for pre-processing, classification, regression, and clustering with support for multi-threaded execution. +- [LIBSVM](https://github.com/cjlin1/libsvm) - Support vector machine library with Java bindings and command-line tools. +- [Neureka](https://github.com/Gleethos/neureka) - A lightweight, platform independent, OpenCL accelerated nd-array/tensor library. +- [oj! Algorithms](https://github.com/optimatika/ojAlgo) - High-performance mathematics, linear algebra and optimisation needed for data science, machine learning and scientific computing. +- [sklearn-java](https://github.com/kVeyra/sklearn-java) - Implements scikit-learn-style machine learning algorithms in pure Java. +- [Smile](https://github.com/haifengl/smile) - Statistical Machine Intelligence and Learning Engine provides a set of machine learning algorithms and a visualization library. +- [Tribuo](https://github.com/oracle/tribuo) - Provides tools for classification, regression, clustering, model development and interfaces with other libraries such as scikit-learn, pytorch and TensorFlow. +- [Weka](https://git.cms.waikato.ac.nz/weka/weka) - Collection of algorithms for data mining tasks ranging from pre-processing to visualization. + +### Messaging + +_Tools that help send messages between clients to ensure protocol independency._ + +- [Aeron](https://github.com/aeron-io/aeron) - Efficient, reliable, unicast and multicast message transport. +- [Apache ActiveMQ](https://github.com/apache/activemq) - Message broker that implements JMS and converts synchronous to asynchronous communication. +- [Apache Camel](https://github.com/apache/camel) - Glues together different transport APIs via Enterprise Integration Patterns. +- [Apache Kafka](https://github.com/apache/kafka) - High-throughput distributed messaging system. +- [Apache Pulsar](https://github.com/apache/pulsar) - Distributed pub/sub-messaging system. +- [Apache RocketMQ](https://github.com/apache/rocketmq) - Fast, reliable, and scalable distributed messaging platform. +- [Apache Qpid for Java](https://qpid.apache.org) - Java messaging clients and brokers implementing AMQP. +- [AutoMQ](https://github.com/AutoMQ/automq) - AutoMQ is a cloud-native, serverless reinvented Kafka that is easily scalable, manage-less and cost-effective. +- [CloudEvents Java SDK](https://github.com/cloudevents/sdk-java) - Java SDK for creating, serializing and transporting CloudEvents. +- [Emissary](https://github.com/joel-jeremy/emissary) - Simple, lightweight, yet FAST messaging library for decoupling messages (requests and events) and message handlers. +- [Hermes](https://github.com/allegro/hermes) - Fast and reliable message broker built on top of Kafka. +- [HiveMQ MQTT Client](https://github.com/hivemq/hivemq-mqtt-client) - Reactive and blocking Java client for MQTT 3.1.1 and MQTT 5. +- [JeroMQ](https://github.com/zeromq/jeromq) - Implementation of ZeroMQ. +- [RabbitMQ Java client](https://github.com/rabbitmq/rabbitmq-java-client) - RabbitMQ client. +- [Pushy](https://github.com/jchambers/pushy) - Java library for sending Apple Push Notification service messages. +- [Simple Java Mail](https://github.com/bbottema/simple-java-mail) - Mailing with a clean and fluent API. +- [Smack](https://github.com/igniterealtime/Smack) - Cross-platform XMPP client library. +- [Svix](https://github.com/svix/svix-webhooks/tree/main/java) - Library for the Svix API to send webhooks and verify signatures. +- [NATS client](https://github.com/nats-io/nats.java) - NATS client. + +### Microservice + +_Tools for creating and managing microservices._ + +- [Armeria](https://github.com/line/armeria) - Asynchronous RPC/REST client/server library built on top of Java 8, Netty, HTTP/2, Thrift and gRPC. +- [Eureka](https://github.com/Netflix/eureka) - REST-based service registry for resilient load balancing and failover. +- [gRPC Spring](https://github.com/grpc-ecosystem/grpc-spring) - Spring Boot integration for building gRPC clients and servers. +- [Helidon](https://github.com/helidon-io/helidon) - Two-style approach for writing microservices: Functional-reactive and as an implementation of MicroProfile. +- [Micronaut](https://github.com/micronaut-projects/micronaut-core) - Modern full-stack framework with focus on modularity, minimal memory footprint and startup time. +- [Nacos](https://github.com/alibaba/nacos) - Dynamic service discovery, configuration and service management platform for building cloud native applications. +- [Quarkus](https://github.com/quarkusio/quarkus) - Kubernetes stack tailored for the HotSpot and Graal VM. +- [Sentinel](https://github.com/alibaba/Sentinel) - Flow control component enabling reliability, resilience and monitoring for microservices. + +### Miscellaneous + +_Everything else._ + +- [JBake](https://github.com/jbake-org/jbake) - Static website generator. +- [JObfuscator](https://www.pelock.com/products/jobfuscator) - Source code obfuscator. +- [yGuard](https://github.com/yWorks/yGuard) - Obfuscation via renaming and shrinking. + +### Mobile Development + +_Tools for creating or managing mobile applications._ + +- [Codename One](https://github.com/codenameone/CodenameOne) - Cross-platform solution for writing native mobile apps. (GPL-2.0-only WITH Classpath-exception-2.0) +- [Gluon Substrate](https://github.com/gluonhq/substrate) - Builds native JavaFX applications for desktop, mobile and embedded targets. +- [MobileUI](https://github.com/MobileUI/mobileui) - Cross-platform framework for developing mobile apps with native UI in Java and Kotlin. +- [Multi-OS Engine](https://github.com/multi-os-engine/multi-os-engine) - Open-source, cross-platform engine to develop native mobile (iOS, Android, etc.) apps. + +### Monitoring + +_Tools that observe/monitor applications in production by providing telemetry._ + +- [Apitally](https://github.com/apitally/apitally-java) - Simple, privacy-focused API monitoring, analytics and request logging for Spring Boot apps. +- [Arthas](https://github.com/alibaba/arthas) - Allows to troubleshoot production issues for applications without modifying code or restarting servers. +- [Automon](https://github.com/stevensouza/automon) - Combines the power of AOP with monitoring and/or logging tools. +- [BTrace](https://github.com/btraceio/btrace) - Dynamic tracing and diagnostics for running JVM applications without restarts. +- [Boot Usage Spring Boot Starter](https://github.com/dhruv-15-03/boot-usage) - Spring Boot Actuator extension providing application startup and runtime metrics including JVM uptime, memory usage, and CPU load. +- [Datadog](https://github.com/DataDog/dd-trace-java) - Modern monitoring & analytics. +- [Dropwizard Metrics](https://github.com/dropwizard/metrics) - Expose metrics via JMX or HTTP and send them to a database. +- [Glowroot](https://github.com/glowroot/glowroot) - Open-source Java APM. +- [HertzBeat](https://github.com/dromara/hertzbeat) - Real-time monitoring system with custom-monitor and agentless. +- [hippo4j](https://github.com/opengoofy/hippo4j/blob/develop/README-EN.md) - Dynamic and observable thread pool framework. +- [inspectIT Ocelot](https://github.com/inspectIT/inspectit-ocelot) - Java agent that collects application performance, tracing and behavioral data. +- [JavaMelody](https://github.com/javamelody/javamelody) - Performance monitoring and profiling. +- [Jolokia](https://github.com/jolokia/jolokia) - JMX over REST. +- [Micrometer](https://github.com/micrometer-metrics/micrometer) - Vendor-neutral metrics/observability facade for the most popular metrics/observability libraries. +- [Micrometer Tracing](https://github.com/micrometer-metrics/tracing) - Vendor-neutral distributed tracing facade for the most popular tracer libraries. +- [OpenTelemetry](https://github.com/open-telemetry/opentelemetry-java) - Instrument, generate, collect, and export telemetry data to help you analyze your software’s performance and behavior. +- [Pinpoint](https://github.com/naver/pinpoint) - Open-source APM tool. +- [Prometheus](https://github.com/prometheus/client_java) - Provides a multi-dimensional data model, DSL, autonomous server nodes and much more. +- [Sentry](https://github.com/getsentry/sentry-java) - Integration with [Sentry](https://github.com/getsentry/sentry), an application error tracking and performance analysis platform. +- [SPM](https://github.com/sematext/sematext-agent-java) - Performance monitor with distributing transaction tracing for JVM apps. +- [zipkin](https://github.com/openzipkin/zipkin) - Distributed tracing system which gathers timing data needed to troubleshoot latency problems in microservice architectures. + +### Native + +_For working with platform-specific native libraries._ + +- [Aparapi](https://git.cleverlibre.org/aparapi/aparapi) - Converts bytecode to OpenCL which allows execution on GPUs. +- [JavaCPP](https://github.com/bytedeco/javacpp) - Provides efficient and easy access to native C++. +- [JCuda](https://github.com/jcuda/jcuda) - JCuda offers Java bindings for CUDA and CUDA-related libraries. +- [JNA](https://github.com/java-native-access/jna) - Work with native libraries without writing JNI. Also provides interfaces to common system libraries. +- [JNR](https://github.com/jnr/jnr-ffi) - Work with native libraries without writing JNI. Also provides interfaces to common system libraries. Same goals as JNA, but faster, and serves as the basis for the upcoming [Project Panama](https://openjdk.java.net/projects/panama). +- [native-lib-loader](https://github.com/scijava/native-lib-loader) - Native library loader for extracting and loading native libraries from Java. + +### Natural Language Processing + +_Libraries that specialize in processing text._ + +- [Apache OpenNLP](https://github.com/apache/opennlp) - Toolkit for machine-learning-based natural language processing. +- [CoreNLP](https://github.com/stanfordnlp/CoreNLP) - Provides a set of fundamental tools for tasks like tagging, named entity recognition, and sentiment analysis. +- [DKPro](https://github.com/dkpro/dkpro-core) - Collection of reusable NLP tools for linguistic pre-processing, machine learning, lexical resources, etc. +- [Hypherator](https://github.com/ejossev/hypherator-java) - Java hyphenation library with iterator-like interface. Can be used out-of-the box - dictionaries for multiple languages are bundled in. +- [LingPipe](https://alias-i.com/lingpipe/) - Toolkit for tasks ranging from POS tagging to sentiment analysis. + +### Networking + +_Libraries for building network clients and servers._ + +- [AISmessages](https://github.com/tbsalling/aismessages) - Decodes NMEA-armoured AIS messages for maritime navigation and safety systems with ITU-R M.1371 support and no runtime dependencies. (CC-BY-NC-SA-4.0) +- [Commons-networking](https://github.com/CiscoSE/commons-networking) - Client for server-sent events (SSE). +- [Apache MINA sshd](https://github.com/apache/mina-sshd) - Java implementation of SSH clients, servers, SFTP and SCP. +- [Atmosphere](https://github.com/Atmosphere/atmosphere) - Real-time transport framework supporting WebSocket, SSE, gRPC and WebTransport. +- [dnsjava](https://github.com/dnsjava/dnsjava) - Java implementation of the DNS protocol. +- [Dubbo](https://github.com/apache/dubbo) - High-performance RPC framework. +- [Grizzly](https://github.com/eclipse-ee4j/grizzly) - NIO framework. Used as a network layer in Glassfish. +- [gRPC-java](https://github.com/grpc/grpc-java) - RPC framework based on protobuf and HTTP/2. +- [java-ngrok](https://github.com/alexdlaird/java-ngrok) - Java wrapper for ngrok; programmatic tunnels for ingress, webhooks, demos, and APIs. +- [Java-WebSocket](https://github.com/TooTallNate/Java-WebSocket) - Lightweight WebSocket client and server implementation. +- [MinimalFTP](https://github.com/Guichaguri/MinimalFTP) - Lightweight, small and customizable FTP server. +- [MINA](https://github.com/apache/mina) - Abstract, event-driven async I/O API for network operations over TCP/IP and UDP/IP via Java NIO. +- [Netty](https://github.com/netty/netty) - Framework for building high-performance network applications. +- [Drift](https://github.com/airlift/drift) - Easy-to-use, annotation-based library for creating Thrift clients and serializable types. +- [ServiceTalk](https://github.com/apple/servicetalk) - Framework built on Netty with APIs tailored to specific protocols and support for multiple programming paradigms. +- [sshj](https://github.com/hierynomus/sshj) - Programmatically use SSH, SCP or SFTP. +- [Socket.IO Client Java](https://github.com/socketio/socket.io-client-java) - Java client for Socket.IO servers. +- [TLS Channel](https://github.com/marianobarrios/tls-channel) - Implements a ByteChannel interface over SSLEngine, enabling easy-to-use (socket-like) TLS. +- [Undertow](https://github.com/undertow-io/undertow) - Web server providing both blocking and non-blocking APIs based on NIO. Used as a network layer in WildFly. +- [urnlib](https://github.com/slub/urnlib) - Represent, parse and encode URNs, as in RFC 2141. +- [Fluency](https://github.com/komamitsu/fluency) - High throughput data ingestion logger to Fluentd and Fluent Bit. + +### ORM + +_APIs that handle the persistence of objects._ + +- [Apache Cayenne](https://github.com/apache/cayenne) - Provides a clean, static API for data access. Also includes a GUI Modeler for working with database mappings, and DB reverse engineering and generation. +- [Doma](https://github.com/domaframework/doma) - Database access framework that verifies and generates source code at compile time using annotation processing as well as native SQL templates called two-way SQL. +- [Ebean](https://github.com/ebean-orm/ebean) - Provides simple and fast data access. +- [EclipseLink](https://github.com/eclipse-ee4j/eclipselink) - Supports a number of persistence standards: JPA, JAXB, JCA and SDO. +- [Hibernate](https://github.com/hibernate/hibernate-orm) - Robust and widely used, with an active community. +- [MyBatis](https://github.com/mybatis/mybatis-3) - Couples objects with stored procedures or SQL statements. +- [mybatis-dynamic](https://github.com/myacelw/mybatis-dynamic) - Code-first dynamic ORM for MyBatis with runtime schema modification. +- [MyBatis-Plus](https://github.com/baomidou/mybatis-plus) - A powerful enhanced toolkit of MyBatis for simplifying development. +- [ObjectiveSql](https://github.com/braisdom/ObjectiveSql) - ActiveRecord ORM for rapid development and convention over configuration. +- [Permazen](https://github.com/permazen/permazen) - Language-natural persistence layer. +- [SimpleFlatMapper](https://github.com/arnaudroger/SimpleFlatMapper) - Simple database and CSV mapper. + +### PaaS + +_Java platform as a service._ + +- [AWS Elastic Beanstalk](https://aws.amazon.com/elasticbeanstalk/) - AWS-based, with support for Tomcat and Jetty. +- [AWS Lambda](https://aws.amazon.com/lambda/) - Serverless computation. +- [Google Cloud](https://cloud.google.com) - Google's cloud infrastructure. +- [Heroku](https://www.heroku.com) - Abstract computing environments. +- [Microsoft Azure](https://azure.microsoft.com/en-us/) - Microsoft's cloud infrastructure. +- [OpenShift](https://www.openshift.com) - Provides additionally an on-premise solution. + +### PDF + +_Tools to help with PDF files._ + +- [Apache FOP](https://github.com/apache/xmlgraphics-fop) - Creates PDFs from XSL-FO. +- [Apache PDFBox](https://github.com/apache/pdfbox) - Toolbox for creating and manipulating PDFs. +- [Nostrum Dynamic Jasper](https://github.com/nostrum-tech/NostrumDynamicJasper) - Provides dynamic report layouts on top of JasperReports. +- [DynamicReports](https://github.com/dynamicreports/dynamicreports) - Simplifies JasperReports. +- [Eclipse BIRT](https://github.com/eclipse-birt/birt) - Report engine for creating PDF and other formats (DOCX, XLSX, HTML, etc) using Eclipse-based visual editor. +- [flyingsaucer](https://github.com/flyingsaucerproject/flyingsaucer) - XML/XHTML and CSS 2.1 renderer. (LGPL-2.1-or-later) +- [GraphCompose](https://github.com/DemchaAV/GraphCompose) - Declarative engine for structured business PDFs with semantic layout, atomic pagination, theme tokens, and native vector charts. +- [iText](https://github.com/itext/itext-java) - Creates PDF files programmatically. +- [JasperReports](https://github.com/Jaspersoft/jasperreports) - Complex reporting engine. +- [jquick-pdf](https://github.com/paohaijiao/jquick-pdf) - Generates PDFs from HTML-like templates and ECharts-style charts using iText 7, without a browser dependency. +- [Open HTML to PDF](https://github.com/openhtmltopdf/openhtmltopdf) - Properly supports modern PDF standards based on flyingsaucer and Apache PDFBox. +- [OpenDataLoader PDF](https://github.com/opendataloader-project/opendataloader-pdf) - Parses PDFs into structured Markdown, JSON and HTML through a Java API and command line. +- [OpenPDF](https://github.com/LibrePDF/OpenPDF) - Open-source iText fork. (LGPL-3.0-only & MPL-2.0) +### Performance analysis + +_Tools for performance analysis, profiling and benchmarking._ + +- [async-profiler](https://github.com/async-profiler/async-profiler) - Low-overhead sampling profiler for CPU, allocation and lock analysis on the JVM. +- [fastThread](https://fastthread.io) - Analyze and visualize thread dumps with a free cloud-based upload interface. +- [GCeasy](https://gceasy.io) - Tool to analyze and visualize GC logs. It provides a free cloud-based upload interface. +- [Heap Seance](https://github.com/SegfaultSorcerer/heap-seance) - Memory leak diagnostics that orchestrates jcmd, jmap, jstat, JFR, Eclipse MAT, and async-profiler into a structured investigation workflow with confidence-based verdicts. +- [jHiccup](https://github.com/giltene/jHiccup) - Logs and records platform JVM stalls. +- [JDK Mission Control](https://github.com/openjdk/jmc) - Profiling and diagnostics suite for JVM applications using Java Flight Recorder. +- [JITWatch](https://github.com/AdoptOpenJDK/jitwatch) - Analyze the JIT compiler optimisations made by the HotSpot JVM. +- [JMH](https://github.com/openjdk/jmh) - Harness for building, running, and analysing nano/micro/milli/macro benchmarks written in Java and other languages targeting the JVM. +- [LatencyUtils](https://github.com/LatencyUtils/LatencyUtils) - Utilities for latency measurement and reporting. +- [JVM Hotpath](https://github.com/sfkamath/jvm-hotpath) - Java agent for line-level execution frequency analysis to identify algorithmic bottlenecks. +- [Argus](https://github.com/rlaope/Argus) - JVM diagnostics CLI for jcmd, JFR, async-profiler, heap analysis and machine-readable health verdicts. + +### Platform + +_Frameworks that are suites of multiple libraries encompassing several categories._ + +#### Apache Commons + +- [BCEL](https://github.com/apache/commons-bcel) - Byte Code Engineering Library - analyze, create, and manipulate Java class files. +- [BeanUtils](https://github.com/apache/commons-beanutils) - Easy-to-use wrappers around the Java reflection and introspection APIs. +- [BSF](https://github.com/apache/commons-bsf) - Bean Scripting Framework - interface to scripting languages, including JSR-223. +- [ClassScan](https://commons.apache.org/sandbox/commons-classscan/) - Find Class interfaces, methods, fields, and annotations without loading. +- [CLI](https://github.com/apache/commons-cli) - Command-line arguments parser. +- [CLI2](https://commons.apache.org/sandbox/commons-cli2/) - Redesign of Commons CLI. +- [Codec](https://github.com/apache/commons-codec) - General encoding/decoding algorithms, e.g. phonetic, base64 or URL. +- [Collections](https://github.com/apache/commons-collections) - Extends or augments the Java Collections Framework. +- [Compress](https://github.com/apache/commons-compress) - Defines an API for working with tar, zip and bzip2 files. +- [Configuration](https://github.com/apache/commons-configuration) - Reading of configuration/preferences files in various formats. +- [Convert](https://commons.apache.org/sandbox/commons-convert/) - Commons-Convert aims to provide a single library dedicated to the task of converting an object of one type to another. +- [CSV](https://github.com/apache/commons-csv) - Component for reading and writing comma separated value files. +- [Daemon](https://github.com/apache/commons-daemon) - Alternative invocation mechanism for unix-daemon-like java code. +- [DBCP](https://github.com/apache/commons-dbcp) - Database connection pooling services. +- [DbUtils](https://github.com/apache/commons-dbutils) - JDBC helper library. +- [Digester](https://github.com/apache/commons-digester) - XML-to-Java-object mapping utility. +- [Email](https://github.com/apache/commons-email) - Library for sending e-mail from Java. +- [Exec](https://github.com/apache/commons-exec) - API for dealing with external process execution and environment management in Java. +- [FileUpload](https://github.com/apache/commons-fileupload) - File upload capability for your servlets and web applications. +- [Finder](https://commons.apache.org/sandbox/commons-finder/) - Java library inspired by the UNIX find command. +- [Flatfile](https://commons.apache.org/sandbox/commons-flatfile/) - Java library for working with flat data structures. +- [Graph](https://github.com/apache/commons-graph) - General purpose graph APIs and algorithms. +- [I18n](https://commons.apache.org/sandbox/commons-i18n/) - Adds the feature of localized message bundles that consist of one or many localized texts that belong together. +- [Id](https://commons.apache.org/sandbox/commons-id/) - Id is a component used to generate identifiers. +- [Imaging](https://github.com/apache/commons-imaging) - Image library. +- [IO](https://github.com/apache/commons-io) - Collection of I/O utilities. +- [Javaflow](https://commons.apache.org/sandbox/commons-javaflow/) - Continuation implementation to capture the state of the application. +- [JCI](https://github.com/apache/commons-jci) - Java Compiler Interface. +- [JCS](https://github.com/apache/commons-jcs) - Java Caching System. +- [Jelly](https://github.com/apache/commons-jelly) - XML based scripting and processing engine. +- [Jexl](https://github.com/apache/commons-jexl) - Expression language which extends the Expression Language of the JSTL. +- [JNet](https://commons.apache.org/sandbox/commons-jnet/) - JNet allows to use dynamically register url stream handlers through the java.net API. +- [JXPath](https://github.com/apache/commons-jxpath) - Utilities for manipulating Java Beans using the XPath syntax. +- [Lang](https://github.com/apache/commons-lang) - Provides extra functionality for classes in java.lang. +- [Logging](https://github.com/apache/commons-logging) - Wrapper around a variety of logging API implementations. +- [Math](https://github.com/apache/commons-math) - Lightweight, self-contained mathematics and statistics components. +- [Monitoring](https://commons.apache.org/sandbox/commons-monitoring/) - Monitoring aims to provide a simple but extensible monitoring solution for Java applications. +- [Nabla](https://commons.apache.org/sandbox/commons-nabla/) - Nabla provides automatic differentiation classes that can generate derivative of any function implemented in the Java language. +- [Net](https://github.com/apache/commons-net) - Collection of network utilities and protocol implementations. +- [OpenPGP](https://commons.apache.org/sandbox/commons-openpgp/) - Interface to signing and verifying data using OpenPGP. +- [Performance](https://commons.apache.org/sandbox/commons-performance/) - Small framework for microbenchmark clients, with implementations for Commons DBCP and Pool. +- [Pipeline](https://commons.apache.org/sandbox/commons-pipeline/) - Provides a set of pipeline utilities designed around work queues that run in parallel to sequentially process data objects. +- [Pool](https://github.com/apache/commons-pool) - Generic object pooling component. +- [RDF](https://github.com/apache/commons-rdf) - Common implementation of RDF 1.1 that could be implemented by systems on the JVM. +- [RNG](https://github.com/apache/commons-rng) - Commons Rng provides implementations of pseudo-random numbers generators. +- [SCXML](https://github.com/apache/commons-scxml) - Implementation of the State Chart XML specification aimed at creating and maintaining a Java SCXML engine. +- [Validator](https://github.com/apache/commons-validator) - Framework to define validators and validation rules in an xml file. +- [VFS](https://github.com/apache/commons-vfs) - Virtual File System component for treating files, FTP, SMB, ZIP and such like as a single logical file system. +- [Weaver](https://github.com/apache/commons-weaver) - Provides an easy way to enhance (weave) compiled bytecode. + +#### Other + +- [CUBA Platform](https://github.com/jmix-framework/jmix) - High-level framework for developing enterprise applications with a rich web interface, based on Spring, EclipseLink and Vaadin. +- [Light-4J](https://github.com/networknt/light-4j/) - Fast, lightweight and productive microservices framework with built-in security. +- [Spring Framework](https://github.com/spring-projects/spring-framework) - Comprehensive application framework for building Java applications. + +### Processes + +_Libraries that help the management of operating system processes._ + +- [ch.vorburger.exec](https://github.com/vorburger/ch.vorburger.exec) - Convenient API around Apache Commons Exec. +- [zt-exec](https://github.com/zeroturnaround/zt-exec) - Provides a unified API to Apache Commons Exec and ProcessBuilder. +- [zt-process-killer](https://github.com/zeroturnaround/zt-process-killer) - Stops processes started from Java or the system processes via PID. + +### Proxy Servers + +_Java proxy and gateway servers for routing and mediating traffic._ + +- [LittleProxy](https://github.com/LittleProxy/LittleProxy) - High performance HTTP proxy atop Netty's event-based networking library. +- [Membrane Service Proxy](https://github.com/membrane/api-gateway) - Open-source, reverse-proxy framework. +- [OpenIG](https://github.com/OpenIdentityPlatform/OpenIG) - High-performance reverse proxy server with specialized session management and credential replay functionality. +- [Spring Cloud Gateway](https://github.com/spring-cloud/spring-cloud-gateway) - API gateway built on Spring Framework and Spring Boot. +- [Zuul](https://github.com/Netflix/zuul) - Gateway service that provides dynamic routing, monitoring, resiliency, security, and more. + +### Reactive libraries + +_Libraries for developing reactive applications._ + +- [Akka](https://github.com/akka/akka) - Toolkit and runtime for building concurrent, distributed, fault-tolerant and event-driven applications. +- [Reactive Streams](https://github.com/reactive-streams/reactive-streams-jvm) - Provides a standard for asynchronous stream processing with non-blocking backpressure. +- [Reactor](https://github.com/reactor/reactor) - A framework for building non-blocking applications on the JVM, providing support for reactive programming. +- [RxJava](https://github.com/ReactiveX/RxJava) - Allows for composing asynchronous and event-based programs using observable sequences. +- [vert.x](https://github.com/eclipse-vertx/vert.x) - Polyglot event-driven application framework. + +### Regular Expressions + +_Libraries and engines for building and evaluating regular expressions._ + +- [dregex](https://github.com/marianobarrios/dregex) - Regular expression engine that uses deterministic finite automata. It supports some Perl-style features and yet retains linear matching time, and also offers set operations. +- [JavaVerbalExpressions](https://github.com/VerbalExpressions/JavaVerbalExpressions) - Library that helps with constructing difficult regular expressions. +- [RE2/J](https://github.com/google/re2j) - Java port of RE2 providing linear-time regular expression matching. +- [Sift](https://github.com/Mirkoddd/Sift) - Type-safe, AST-based Regex Builder focused on readability and ReDoS prevention. + +### REST Frameworks + +_Frameworks specifically for creating RESTful services._ + +- [Dropwizard](https://github.com/dropwizard/dropwizard) - Opinionated framework for setting up modern web applications with Jetty, Jackson, Jersey and Metrics. +- [Elide](https://github.com/yahoo/elide) - Opinionated framework for JSON- or GraphQL-APIs based on a JPA data model. +- [hate](https://github.com/blackdoor/hate) - Builds hypermedia-friendly objects according to HAL specification. +- [Jersey](https://github.com/eclipse-ee4j/jersey) - JAX-RS reference implementation. +- [OfficeFloor](https://github.com/officefloor/OfficeFloor) - Spring Boot add-on that adds explicit function orchestration to REST endpoints, with each endpoint's steps, branches and error flows in one YAML file whose directory path maps to the URL. +- [RESTEasy](https://github.com/resteasy/resteasy) - Fully certified and portable implementation of the JAX-RS specification. +- [RestExpress](https://github.com/RestExpress/RestExpress) - Thin wrapper on the JBoss Netty HTTP stack that provides scaling and performance. +- [Restlet Framework](https://github.com/restlet/restlet-framework-java) - Pioneering framework with powerful routing and filtering capabilities, and a unified client and server API. +- [Spark](https://github.com/sparkjavateam/spark) - Sinatra inspired framework. +- [springdoc-openapi](https://github.com/springdoc/springdoc-openapi) - Automates the generation of API documentation using Spring Boot projects. +- [Spring HATEOAS](https://github.com/spring-projects/spring-hateoas) - Standalone and Spring support for building hypermedia-based APIs using HAL, HAL FORMS, Collection+JSON, ALPS and UBER. +- [Swagger Java](https://swagger.io) - Java libraries for generating, parsing and serving OpenAPI definitions. +- [openapi-generator](https://github.com/OpenAPITools/openapi-generator) - Allows generation of API client libraries, SDKs, server stubs, documentation and configuration automatically given an OpenAPI Spec. + +### Science + +_Libraries for scientific computing, analysis and visualization._ + +- [BioJava](https://github.com/biojava/biojava) - Facilitates processing biological data by providing algorithms, file format parsers, sequencing and 3D visualization commonly used in bioinformatics. +- [Chart-FX](https://github.com/fair-acc/chart-fx) - Scientific charting library with focus on performance optimised real-time data visualisation at 25 Hz update rates for large data sets. +- [DataMelt](https://datamelt.org/) - Environment for scientific computation, data analysis and data visualization. (GPL-3.0-or-later) +- [Erdos](https://github.com/Erdos-Graph-Framework/Erdos) - Modular, light and easy graph framework for theoretic algorithms. +- [Gephi](https://github.com/gephi/gephi) - Cross-platform for visualizing and manipulating large graph networks. +- [JFreeChart](https://github.com/jfree/jfreechart) - 2D chart library for Swing, JavaFX and server-side applications. +- [JGraphT](https://github.com/jgrapht/jgrapht) - Graph library that provides mathematical graph-theory objects and algorithms. +- [jSciPy](https://github.com/hissain/jscipy) - jSciPy is a Java library designed for scientific computing, offering functionalities inspired by popular scientific computing libraries. It currently provides modules for signal processing, including Butterworth filters, peak finding algorithms, and an RK4 solver for ordinary differential equations. +- [LogicNG](https://github.com/logic-ng/LogicNG) - Library for creating, manipulating and solving Boolean and Pseudo-Boolean formulas. +- [Mines Java Toolkit](https://github.com/MinesJTK/jtk) - Library for geophysical scientific computation, visualization and digital signal analysis. +- [Orekit](https://github.com/CS-SI/Orekit) - A low level space flight dynamics library providing basic elements (orbits, dates, attitude, frames...) and various algorithms (conversions, propagations, pointing...) to handle them. +- [Orson-Charts](https://github.com/jfree/orson-charts) - Generates a wide variety of 3D charts that can be displayed with Swing and JavaFX or exported to PDF, SVG, PNG and JPEG. +- [XChart](https://github.com/knowm/XChart) - Light-weight library for plotting data. Many customizable chart types are available. + +### Scripting + +_Tools and runtimes for using Java or Java-like languages as scripts._ + +- [JBang](https://github.com/jbangdev/jbang) - JBang makes it easy to use Java for scripting. It lets you use a single file for code and dependency management and allows you to run it directly. +- [JPad](https://jpad.io) - Snippet runner. +- [JQuick Java](https://github.com/paohaijiao/jquick-java) - Java-like scripting language for dynamic rule engines with XML orchestration and Java interoperability. + +### Search + +_Engines that index documents for search and analysis._ + +- [Apache Lucene](https://github.com/apache/lucene) - High-performance, full-featured, cross-platform, text search engine library. +- [Apache Solr](https://github.com/apache/solr) - Enterprise search engine optimized for high-volume traffic. +- [Elasticsearch](https://github.com/elastic/elasticsearch) - Distributed, multitenant-capable, full-text search engine with a RESTful web interface and schema-free JSON documents. +- [Elasticsearch Java Client](https://github.com/elastic/elasticsearch-java) - Official typed Java client for Elasticsearch. +- [OpenSearch](https://github.com/opensearch-project/OpenSearch) - Distributed search and analytics engine derived from Elasticsearch. +- [Viglet Turing ES](https://github.com/openviglet/turing-ce) - Self-hosted enterprise search platform with faceted, semantic and hybrid search, RAG, AI agents and pluggable Solr, Elasticsearch or Lucene backends. + +### Security + +_Libraries that handle security, authentication, authorization or session management._ + +- [Apache Shiro](https://github.com/apache/shiro) - Performs authentication, authorization, cryptography and session management. +- [Ayza](https://github.com/Hakky54/ayza) - High-level SSL configuration builder for configuring HTTP clients and servers with SSL/TLS. +- [Bouncy Castle](https://github.com/bcgit/bc-java) - All-purpose cryptographic library and JCA provider offering a wide range of functions, from basic helpers to PGP/SMIME operations. +- [Certificate Ripper](https://github.com/Hakky54/certificate-ripper) - CLI tool and library for extracting and exporting server certificates from HTTPS endpoints. +- [Dependency-Track](https://github.com/DependencyTrack/dependency-track) - Software composition analysis platform for identifying supply-chain risk. +- [OWASP Dependency-Check](https://github.com/dependency-check/DependencyCheck) - Detects publicly disclosed vulnerabilities contained within a project's dependencies. +- [Cryptomator](https://github.com/cryptomator/cryptomator) - Multiplatform, transparent, client-side encryption of files in the cloud. +- [jjwt](https://github.com/jwtk/jjwt) - JSON web token for Java and Android. +- [jwt-java](https://github.com/BastiaanJansen/jwt-java) - Easily create and parse JSON Web Tokens and create customized JWT validators using a fluent API. +- [Jwks RSA](https://github.com/auth0/jwks-rsa-java) - JSON Web Key Set parser. +- [Jasypt Spring Boot](https://github.com/ulisesbocchio/jasypt-spring-boot) - Integrates encrypted properties with Spring Boot applications. +- [Keycloak](https://github.com/keycloak/keycloak) - Integrated SSO and IDM for browser apps and RESTful web services. +- [Nbvcxz](https://github.com/GoSimpleLLC/nbvcxz) - Advanced password strength estimation. +- [OpenAM](https://github.com/OpenIdentityPlatform/OpenAM) - Access management solution that includes authentication, SSO, authorization, federation, entitlements and web services security. +- [OTP-Java](https://github.com/BastiaanJansen/OTP-Java) - One-time password generator library according to RFC 4226 (HOTP) and RFC 6238 (TOTP). +- [pac4j](https://github.com/pac4j/pac4j) - Security engine. +- [Passay](https://github.com/vt-middleware/passay) - Enforce password policy by validating candidate passwords against a configurable rule set. +- [Password4j](https://github.com/Password4j/password4j) - User-friendly cryptographic library that supports Argon2, Bcrypt, Scrypt, PBKDF2 and various other cryptographic hash functions. +- [SecurityBuilder](https://github.com/tersesystems/securitybuilder) - Fluent Builder API for JCA and JSSE classes and especially X.509 certificates. +- [ScribeJava](https://github.com/scribejava/scribejava) - OAuth client library supporting OAuth 1.0a, OAuth 2.0 and numerous providers. +- [Spring Authorization Server](https://github.com/spring-projects/spring-authorization-server) - Implements OAuth 2.1 and OpenID Connect authorization server specifications for Spring. +- [Themis](https://github.com/cossacklabs/themis) - Multi-platform high-level cryptographic library provides easy-to-use encryption for protecting sensitive data: secure messaging with forward secrecy, secure data storage (AES256GCM); suits for building end-to-end encrypted applications. +- [Tink](https://github.com/tink-crypto/tink-java) - Provides a simple and misuse-proof API for common cryptographic tasks. +- [Topaz](https://github.com/aserto-dev/topaz) - Fine-grained authorization for applications with support for RBAC, ABAC, and ReBAC. +- [WebAuthn4J](https://github.com/webauthn4j/webauthn4j) - Server-side WebAuthn and passkey verification library. +- [MOSS](https://github.com/mosscomputing/moss-java) - Cryptographic signing for AI agents using ML-DSA-44 post-quantum signatures, creating audit trails for attribution and compliance. + +### Serialization + +_Libraries that handle serialization with high efficiency._ + +- [Apache Avro](https://github.com/apache/avro) - Data interchange format with dynamic typing, untagged data, and absence of manually assigned IDs. +- [Apache Fory](https://github.com/apache/fory) - High-performance object graph serialization framework with JIT and zero-copy support. +- [Apache Orc](https://github.com/apache/orc) - Fast and efficient columnar storage format for Hadoop-based workloads. +- [Apache Parquet](https://github.com/apache/parquet-java) - Columnar storage format based on assembly algorithms from Google's paper on Dremel. +- [Apache Thrift](https://github.com/apache/thrift) - Data interchange format that originated at Facebook. +- [FlatBuffers](https://github.com/google/flatbuffers) - Memory-efficient serialization library that can access serialized data without unpacking and parsing it. +- [Kryo](https://github.com/EsotericSoftware/kryo) - Fast and efficient object graph serialization framework. +- [MessagePack](https://github.com/msgpack/msgpack-java) - Efficient binary serialization format. +- [Protobuf](https://github.com/protocolbuffers/protobuf) - Google's data interchange format. +- [SBE](https://github.com/aeron-io/simple-binary-encoding) - Simple Binary Encoding, one of the fastest message formats around. +- [Wire](https://github.com/square/wire) - Clean, lightweight protocol buffers. +- [XMLBeam](https://github.com/SvenEwald/xmlbeam) - Processes XML by using annotations or XPath within code. + +### Server + +_Servers specifically used to deploy applications._ + +- [Apache Tomcat](https://github.com/apache/tomcat) - Robust, all-round server for Servlet and JSP. +- [Apache TomEE](https://github.com/apache/tomee) - Tomcat plus Java EE. +- [Jetty](https://github.com/jetty/jetty.project) - Provides a Web server and javax.servlet container, plus support for HTTP/2, WebSocket, OSGi, JMX, JNDI, JAAS and many other integrations. +- [WildFly](https://github.com/wildfly/wildfly) - Formerly known as JBoss and developed by Red Hat with extensive Java EE support. + +### Spreadsheet + +_Libraries for reading, writing and generating spreadsheet files._ + +- [Apache Fesod](https://github.com/apache/fesod) - Memory-efficient library for reading and writing large spreadsheet files. +- [Apache POI](https://github.com/apache/poi) - Supports OOXML (XLSX, DOCX, PPTX) as well as OLE2 (XLS, DOC or PPT). +- [fastexcel](https://github.com/dhatim/fastexcel) - High performance library to read and write large Excel (XLSX) worksheets. +- [jackson-dataformat-spreadsheet](https://github.com/scndry/jackson-dataformat-spreadsheet) - Jackson dataformat module for reading and writing Excel (XLSX/XLS) as POJOs via `ObjectMapper`. +- [Jxls](https://github.com/jxlsteam/jxls) - Generates Excel reports from spreadsheet templates. +- [Sheetz](https://github.com/chitralabs/sheetz) - Reads and writes Excel, CSV and ODS files with annotation mapping, streaming, styling and validation. +- [zerocell](https://github.com/creditdatamw/zerocell) - Annotation-based API for reading data from Excel sheets into POJOs with focus on reduced overhead. + +### Template Engine + +_Tools that substitute expressions in a template._ + +- [Freemarker](https://github.com/apache/freemarker) - Library to generate text output (HTML web pages, e-mails, configuration files, source code, etc.) based on templates and changing data. +- [Handlebars.java](https://github.com/jknack/handlebars.java) - Logicless and semantic Mustache templates. +- [Jamal](https://github.com/verhas/jamal) - Extendable template engine embedded into Maven/JavaDoc, supporting multiple extensions (Groovy, Ruby, JavaScript, JShell, PlantUml) with support for snippet handling. +- [jstachio](https://github.com/jstachio/jstachio) - Typesafe Mustache templating engine. +- [jte](https://github.com/casid/jte) - Compiles to classes, and uses an easy syntax, several features to make development easier and provides fast execution and a small footprint. +- [Pebble](https://github.com/PebbleTemplates/pebble) - Inspired by Twig and separates itself with its inheritance feature and its easy-to-read syntax. It ships with built-in autoescaping for security and it includes integrated support for internationalization. +- [Rocker](https://github.com/fizzed/rocker) - Optimized, memory efficient and speedy template engine producing statically typed, plain objects. +- [StringTemplate](https://github.com/antlr/stringtemplate4) - Template engine for generating source code, web pages, emails, or any other formatted text output. +- [Thymeleaf](https://github.com/thymeleaf/thymeleaf) - Aims to be a substitute for JSP and works for XML files. + +### Testing + +_Tools that test from model to the view._ + +#### BDD + +_Testing for the software development process that emerged from TDD and was heavily influenced by DDD and OOAD._ + +- [Cucumber](https://github.com/cucumber/cucumber-jvm) - Provides a way to describe features in a plain language which customers can understand. +- [J8Spec](https://github.com/j8spec/j8spec) - Follows a Jasmine-like syntax. +- [JBehave](https://github.com/jbehave/jbehave-core) - Extensively configurable framework that describes stories. +- [JGiven](https://github.com/TNG/JGiven) - Provides a fluent API which allows for simpler composition. +- [Kensa](https://github.com/kensa-dev/kensa) - Code-first BDD framework for Java and Kotlin that generates interactive HTML reports and sequence diagrams from test code. +- [Serenity BDD](https://github.com/serenity-bdd/serenity-core) - Automated Acceptance testing and reporting library that works with Cucumber, JBehave and JUnit to make it easier to write high quality executable specifications. + +#### Fixtures + +_Everything related to the creation and handling of random data._ + +- [AutoParams](https://github.com/AutoParams/AutoParams) - Supports generating test data or combining scenarios for parameterized tests. +- [Datafaker](https://github.com/datafaker-net/datafaker) - Modern fake data generator forked from Java Faker. +- [jFairy](https://github.com/SkillPanel/jfairy) - Fake data generator. +- [Instancio](https://github.com/instancio/instancio) - Automates data setup in unit tests by generating fully-populated, reproducible objects. Includes JUnit 5 extension. +- [Randomized Testing](https://github.com/randomizedtesting/randomizedtesting) - JUnit test runner and plugins for running JUnit tests with pseudo-randomness. +- [JMock](https://github.com/xcancloud/JMock) - JMock is a high-performance data generation and simulation component library implemented in Java. + +#### Frameworks + +_Provide environments to run tests for a specific use case._ + +- [BitDive Java Agent](https://github.com/bitDive/java-producer) - Java agent that captures runtime traces, SQL queries and HTTP payloads for BitDive testing. +- [JUnit](https://github.com/junit-team/junit-framework) - Common testing framework. +- [jqwik](https://github.com/jqwik-team/jqwik) - Engine for property-based testing built on JUnit 5. +- [PIT](https://github.com/hcoles/pitest) - Fast mutation-testing framework for evaluating fault-detection abilities of existing JUnit or TestNG test suites. +- [Robolectric](https://github.com/robolectric/robolectric) - Runs Android tests on the JVM without an emulator or device. +- [selenium](https://github.com/SeleniumHQ/selenium) - Browser automation framework and ecosystem. +- [Selenium Boot](https://github.com/seleniumboot/selenium-boot) - Zero-boilerplate Selenium + TestNG framework with auto driver management, smart retry, self-healing locators, AI failure analysis, and a built-in HTML report. + +#### Integration + +_Tools for integration, service and contract testing._ + +- [Arquillian](https://github.com/arquillian/arquillian-core) - Integration and functional testing platform for Java EE containers. +- [cdi-test](https://github.com/guhilling/cdi-test) - JUnit extension for easy and efficient testing of CDI components. +- [Citrus](https://github.com/citrusframework/citrus) - Integration testing framework that focuses on both client- and server-side messaging. +- [GreenMail](https://github.com/greenmail-mail-test/greenmail) - In-memory email server for integration testing. Supports SMTP, POP3 and IMAP including SSL. +- [Hoverfly Java](https://github.com/SpectoLabs/hoverfly-java) - Native bindings for Hoverfly, a proxy which allows you to simulate HTTP services. +- [Karate](https://github.com/karatelabs/karate) - DSL that combines API test-automation, mocks and performance-testing making testing REST/HTTP services easy. +- [Pact JVM](https://github.com/pact-foundation/pact-jvm) - Consumer-driven contract testing. +- [REST Assured](https://github.com/rest-assured/rest-assured) - DSL for easy testing of REST/HTTP services. +- [Testcontainers](https://github.com/testcontainers/testcontainers-java) - Provides throwaway instances of common databases, Selenium web browsers, or anything else that can run in a Docker container. +- [WebTau](https://github.com/testingisdocumenting/webtau) - Test across REST-API, Graph QL, Browser, Database, CLI and Business Logic with consistent set of matchers and concepts. +- [weld-testing](https://github.com/weld/weld-testing) - Set of test framework extensions (JUnit 4, JUnit 5, Spock) to enhance the testing of CDI components via Weld. Supports Weld 5. + +#### Matchers + +_Libraries that provide custom matchers._ + +- [AssertJ](https://github.com/assertj/assertj) - Fluent assertions that improve readability. +- [JsonUnit](https://github.com/lukas-krecan/JsonUnit) - Library that simplifies JSON comparison in tests. +- [Truth](https://github.com/google/truth) - Google's fluent assertion and proposition framework. +- [XMLUnit](https://github.com/xmlunit/xmlunit) - Simplifies testing for XML output. + +#### Miscellaneous + +_Other stuff related to testing._ + +- [Awaitility](https://github.com/awaitility/awaitility) - DSL for synchronizing asynchronous operations. +- [ConcurrentUnit](https://github.com/jhalterman/concurrentunit) - Toolkit for testing multi-threaded and asynchronous applications. +- [ConsoleCaptor](https://github.com/Hakky54/console-captor) - Captures console output for unit testing purposes. +- [junit-dataprovider](https://github.com/TNG/junit-dataprovider) - TestNG-like data provider/runner for JUnit. +- [junit-pioneer](https://github.com/junit-pioneer/junit-pioneer) - JUnit 5 extension pack, pushing the frontiers on Jupiter. +- [LogCaptor](https://github.com/Hakky54/log-captor) - Captures log entries for unit testing purposes. +- [log-capture](https://github.com/dm-drogeriemarkt/log-capture) - Captures log entries and provides assertions for unit and integration testing. +- [Selfie](https://github.com/diffplug/selfie) - Snapshot testing (inline and on disk). +- [skipper-java](https://github.com/get-skipper/skipper-java) - Real-time test execution control via Google Spreadsheet, enabling instant toggle without code changes. +- [Stebz](https://github.com/stebz/stebz) - Multi-approach framework for test steps managing. +- [test-watch-maven-plugin](https://github.com/albilu/test-watch-maven-plugin) - Maven plugin providing Vitest-inspired watch mode for tests with smart selection and parallel execution. + +#### Mocking + +_Tools which mock collaborators to help testing single, isolated units._ + +- [JMockit](https://github.com/jmockit/jmockit1) - Integration testing, API mocking and faking, and code coverage. +- [Mockito](https://github.com/mockito/mockito) - Mocking framework that lets you write tests with a clean and simple API. +- [MockServer](https://github.com/mock-server/mockserver-monorepo) - Allows mocking of systems integrated with HTTPS. +- [Moco](https://github.com/dreamhead/moco) - Concise web services for stubs and mocks. +- [WireMock](https://github.com/wiremock/wiremock) - Stubs and mocks web services. +- [EasyMock](https://github.com/easymock/easymock) - EasyMock is a Java library that provides an easy way to use Mock Objects in unit testing. + +#### Performance + +_Tools for load and performance testing._ + +- [Apache JMeter](https://github.com/apache/jmeter) - Functional testing and performance measurements. +- [Gatling](https://github.com/gatling/gatling) - Load testing tool designed for ease of use, maintainability and high performance. +- [JMeter DSL.java](https://github.com/abstracta/jmeter-java-dsl) - Load tests with JMeter as simple as a JUnit test. + +### Utility + +_Libraries which provide general utility functions._ + +- [bucket4j](https://github.com/bucket4j/bucket4j) - Rate limiting library based on token-bucket algorithm. +- [cactoos](https://github.com/yegor256/cactoos) - Collection of object-oriented primitives. +- [fswatch](https://github.com/vorburger/ch.vorburger.fswatch) - Micro library to watch for directory file system changes, simplifying java.nio.file.WatchService. +- [Guava](https://github.com/google/guava) - Collections, caching, primitives support, concurrency libraries, common annotations, string processing, I/O, and more. +- [ISBN core](https://github.com/ladutsko/isbn-core) - A small library that contains a representation object of ISBN-10 and ISBN-13 and tools to parse, validate and format one. +- [JEmoji](https://github.com/felldo/JEmoji) - An auto-generated emoji library that provides type-safe direct access to emojis and alias support for Discord, Slack, GitHub and many more features. +- [Java Diff Utils](https://github.com/java-diff-utils/java-diff-utils) - Utilities for text or data comparison and patching. +- [Java UUID Generator](https://github.com/cowtowncoder/java-uuid-generator) - Generates standard UUID versions including time-ordered UUIDv6 and UUIDv7. +- [java-util](https://github.com/jdereg/java-util) - Zero-dependency, high-performance utilities featuring Converter (universal type conversion), DeepEquals, CaseInsensitiveMap, TTLCache, CompactMap, MultiKeyMap, and object graph traversal. +- [Jimfs](https://github.com/google/jimfs) - In-memory file system. +- [JKScope](https://github.com/evpl/jkscope) - Java scope functions inspired by Kotlin. +- [java-refined](https://github.com/JunggiKim/java-refined) - Zero-dependency refinement types for Java 8+ with type-safe wrappers covering numerics, strings, and collections. +- [PipelinR](https://github.com/sizovs/pipelinr) - Small utility library for using handlers and commands with pipelines. +- [Semver4j](https://github.com/semver4j/semver4j) - Lightweight library that helps you handling semantic versioning with different modes. +- [Underscore-java](https://github.com/javadev/underscore-java) - Port of Underscore.js functions. +- [Zip4j](https://github.com/srikanth-lingala/zip4j) - Reads, writes, encrypts and streams ZIP files. + +### Version Managers + +_Utilities that help create the development shell environment and switch between different Java versions._ + +- [jabba](https://github.com/Jabba-Team/jabba) - Java Version Manager inspired by nvm. Supports macOS, Linux and Windows. +- [jenv](https://github.com/jenv/jenv) - Java Version Manager inspired by rbenv. Can configure globally or per project. Tested on Debian and macOS. +- [SDKMan](https://github.com/sdkman/sdkman-cli) - Java Version Manager inspired by RVM and rbenv. Supports UNIX-based platforms and Windows. + +### Web Crawling + +_Libraries that analyze the content of websites._ + +- [Apache Nutch](https://github.com/apache/nutch) - Highly extensible, highly scalable web crawler for production environments. +- [crawlberg](https://github.com/xberg-io/crawlberg) - Crawls and scrapes websites through a Java binding with Markdown conversion and optional browser rendering. +- [jsoup](https://github.com/jhy/jsoup) - Scrapes, parses, manipulates and cleans HTML. +- [StormCrawler](https://github.com/apache/stormcrawler) - SDK for building low-latency and scalable web crawlers. +- [webmagic](https://github.com/code4craft/webmagic) - Scalable crawler with downloading, url management, content extraction and persistent. + +### Web Frameworks + +_Frameworks that handle the communication between the layers of a web application._ + +- [ActiveJ](https://github.com/activej/activej) - Lightweight asynchronous framework built from the ground up for developing high-performance web applications. +- [Apache Tapestry](https://github.com/apache/tapestry-5) - Component-oriented framework for creating dynamic, robust, highly scalable web applications. +- [Apache Wicket](https://github.com/apache/wicket) - Component-based web application framework similar to Tapestry, with a stateful GUI. +- [Blade](https://github.com/lets-blade/blade) - Lightweight, modular framework that aims to be elegant and simple. +- [Bootique](https://github.com/bootique/bootique) - Minimally opinionated framework for runnable apps. +- [Javalin](https://github.com/javalin/javalin) - Microframework for web applications. +- [Jooby](https://github.com/jooby-project/jooby) - Scalable, fast and modular micro-framework that offers multiple programming models. +- [Ninja](https://github.com/ninjaframework/ninja) - Full-stack web framework. +- [Pippo](https://github.com/pippo-java/pippo) - Small, highly modularized, Sinatra-like framework. +- [Play](https://github.com/playframework/playframework) - Built on Akka, it provides predictable and minimal resource consumption (CPU, memory, threads) for highly-scalable applications in Java and Scala. +- [PrimeFaces](https://github.com/primefaces/primefaces) - JSF framework with both free and commercial/support versions and frontend components. +- [Ratpack](https://github.com/ratpack/ratpack) - Set of libraries that facilitate fast, efficient, evolvable and well-tested HTTP applications. +- [Spring Boot](https://github.com/spring-projects/spring-boot) - Framework for creating stand-alone, production-grade Spring applications. +- [Takes](https://github.com/yegor256/takes) - Opinionated web framework which is built around the concepts of True Object-Oriented Programming and immutability. +- [tinystruct](https://github.com/tinystruct/tinystruct) - Lightweight, pluggable framework for building Java applications with CLI, HTTP, and modular extension support. +- [Vaadin](https://vaadin.com) - Full-stack Java platform for building browser applications with server-side components. +- [WebForms Core](https://github.com/webforms-core) - A technology for managing HTML tags from the server. +- [Erupt](https://github.com/erupts/erupt) - Annotation-Driven Low-Code & JPA Visualization. + +### Workflow Orchestration Engines + +_Engines for orchestrating long-running workflows and business processes._ + +- [Cadence Java Client](https://github.com/cadence-workflow/cadence-java-client) - Java client and workflow framework for the Cadence orchestration service. +- [Activiti](https://github.com/Activiti/Activiti) - Embeddable BPMN workflow and business process engine. +- [Apache DolphinScheduler](https://github.com/apache/dolphinscheduler) - Distributed workflow orchestration platform with visual and API-driven scheduling. +- [Conductor](https://github.com/conductor-oss/conductor) - Event-driven workflow engine for distributed applications and AI agents. +- [flowable](https://github.com/flowable/flowable-engine) - Compact and efficient workflow and business process management platform. +- [Maestro](https://github.com/Netflix/maestro) - Workflow orchestration engine developed by Netflix. +- [Temporal Java SDK](https://github.com/temporalio/sdk-java) - Java SDK for writing durable workflows and activities on Temporal. + +## Resources + +### Related Awesome Lists + +_Awesome Lists related to the Java & JVM ecosystem._ + +- [Awesome Annotation Processing](https://github.com/gunnarmorling/awesome-annotation-processing) +- [Awesome Graal](https://github.com/neomatrix369/awesome-graal) +- [Awesome Gradle Plugins](https://github.com/ksoichiro/awesome-gradle) +- [Awesome Java libraries and hidden gems](https://libs.tech/java) +- [Awesome J2ME](https://github.com/hstsethi/awesome-j2me) +- [AwesomeJavaFX](https://github.com/mhrimaz/AwesomeJavaFX) +- [Awesome JVM](https://github.com/deephacks/awesome-jvm) +- [Awesome Microservices](https://github.com/mfornos/awesome-microservices) +- [Awesome REST](https://github.com/marmelab/awesome-rest) +- [Awesome Selenium](https://github.com/christian-bromann/awesome-selenium) +- [Awesome Hybris](https://github.com/eminyagiz42/awesome-hybris) +- [ciandcd](https://github.com/ciandcd/awesome-ciandcd) +- [Useful Java Links](https://github.com/Vedenin/useful-java-links) + +### Communities + +_Active discussions._ + +- [foojay.io](https://foojay.io) +- [r/java](https://www.reddit.com/r/java/) - Subreddit for the Java community. +- [Stack Overflow](https://stackoverflow.com/questions/tagged/java) - Question/answer platform. + +### Guides and References + +_Guides, tutorials, examples and practical references for Java developers._ + +- [Design Patterns](https://github.com/iluwatar/java-design-patterns) - Implementation and explanation of the most common design patterns. +- [FizzBuzz Enterprise Edition](https://github.com/EnterpriseQualityCoding/FizzBuzzEnterpriseEdition) - No-nonsense implementation of FizzBuzz made by serious businessmen for serious business purposes. (No explicit license) +- [Google Java Style](https://google.github.io/styleguide/javaguide.html) +- [Java Algorithms and Clients](https://algs4.cs.princeton.edu/code) +- [Java Concurrency Checklist](https://github.com/code-review-checklists/java-concurrency) +- [Java Developer Roadmap](https://github.com/s4kibs4mi/java-developer-roadmap) +- [Java Evolved](https://github.com/javaevolved/javaevolved.github.io) - Side-by-side comparisons of legacy and modern Java patterns. +- [Modern Java - A Guide to Java 8](https://github.com/winterbe/java8-tutorial) - Popular Java 8 guide. +- [TheCodeForge Java Tutorials](https://thecodeforge.io/java/) +- [Which JDK](https://github.com/whichjdk/whichjdk.com) - Overview of common JVMs with pros and cons. + +### Influential Books + +_Books that made a big impact and are still worth reading._ + +- [Core Java Volume I--Fundamentals](https://www.amazon.com/Core-Java-I-Fundamentals-10th/dp/0134177304) +- [Core Java, Volume II--Advanced Features](https://www.amazon.com/Core-Java-II-Advanced-Features-10th/dp/0134177290) +- [Effective Java (3rd Edition)](https://www.amazon.com/Effective-Java-3rd-Joshua-Bloch/dp/0134685997) +- [Head First Java (3rd Edition)](https://www.oreilly.com/library/view/head-first-java/9781492091646/) +- [Java Concurrency in Practice](https://www.amazon.com/Java-Concurrency-Practice-Brian-Goetz/dp/0321349601) +- [The Well-Grounded Java Developer (2nd Edition)](https://www.manning.com/books/the-well-grounded-java-developer-second-edition) +- [Thinking in Java](https://www.amazon.com/Thinking-Java-Edition-Bruce-Eckel/dp/0131872486) + +### Podcasts and Screencasts + +_Something to look at or listen to while programming._ + +- [140 Second Ducklings](https://twitter.com/debugagent/status/1491075324805001219) - Short videos on Twitter explaining Java debugging in depth. +- [A Bootiful Podcast](https://bootifulpodcast.fm) +- [Foojay Podcast](https://foojay.io/today/category/podcast/) +- [Inside Java](https://inside.java/podcast) - Official podcast. +- [Java Off Heap](https://www.javaoffheap.com) + +### People + +_Active accounts to follow. Descriptions from their socials._ + +- [Adam Bien](https://twitter.com/AdamBien) - Freelance author, JavaOne Rockstar speaker, consultant, Java Champion. +- [Aleksey ShipilΓ«v](https://twitter.com/shipilev) - Performance geek, benchmarking czar, concurrency bug hunter. +- [Antonio Goncalves](https://twitter.com/agoncal) - Java Champion, JUG Leader, Devoxx France, Java EE 6/7, JCP, Author. +- [Arun Gupta](https://twitter.com/arungupta) - Java Champion, JavaOne Rockstar, JUG Leader, Devoxx4Kids-er, VP of Developer Advocacy at Couchbase. +- [Brian Goetz](https://bsky.app/profile/briangoetz.bsky.social) - Java Language Architect at Oracle. +- [Bruno Borges](https://twitter.com/brunoborges) - Product Manager/Java Jock at Oracle. +- [Chris Engelbert](https://twitter.com/noctarius2k) - Open Source Enthusiast, Speaker, Developer, Developer Advocacy at TimescaleDB. +- [Chris Richardson](https://bsky.app/profile/crichardson.bsky.social) - Software architect, consultant, and serial entrepreneur, Java Champion, JavaOne Rock Star, \*POJOs in Action- author. +- [Ed Burns](https://twitter.com/edburns) - Consulting Member of the Technical Staff at Oracle. +- [Eugen Paraschiv](https://twitter.com/baeldung) - Author of the Spring Security Course. +- [Heinz Kabutz](https://twitter.com/heinzkabutz) - Java Champion, speaker, author of The Java Specialists' Newsletter, concurrency performance expert. +- [Holly Cummins](https://twitter.com/holly_cummins) - Technical Lead of IBM London's Bluemix Garage, Java Champion, developer, author, JavaOne rockstar. +- [James Weaver](https://twitter.com/JavaFXpert) - Java/JavaFX/IoT developer, author and speaker. +- [Java](https://twitter.com/java) - Official Java Twitter account. +- [Javin Paul](https://twitter.com/javinpaul) - Well-known Java blogger. +- [Josh Long](https://twitter.com/starbuxman) - Spring Advocate at Pivotal, author of O'Reilly's Cloud Native Java- and Building Microservices with Spring Boot, JavaOne Rock Star. +- [Lukas Eder](https://bsky.app/profile/lukaseder.bsky.social) - Java Champion, speaker, Founder and CEO Data Geekery (jOOQ). +- [Mani Sarkar](https://twitter.com/theNeomatrix369) - Java champion, Polyglot, Software Crafter involved with @graalvm, AI/ML/DL, Data Science, Developer communities, speaker & blogger. Creator of couple of awesome lists like this one. +- [Mario Fusco](https://twitter.com/mariofusco) - RedHatter, JUG coordinator, frequent speaker and author. +- [Mark Heckler](https://twitter.com/MkHeck) - Pivotal Principal Technologist and Developer Advocate, conference speaker, published author, and Java Champion, focusing on Internet of Things and the cloud. +- [Markus Eisele](https://twitter.com/myfear) - Java EE evangelist, Red Hat. +- [Martijn Verburg](https://twitter.com/karianna) - London JUG co-leader, speaker, author, Java Champion and much more. +- [Martin Thompson](https://twitter.com/mjpt777) - Pasty faced performance gangster. +- [Monica Beckwith](https://twitter.com/mon_beck) - Performance consultant, JavaOne Rock Star. +- [OpenJDK](https://twitter.com/OpenJDK) - Official OpenJDK account. +- [Peter Lawrey](https://twitter.com/PeterLawrey) - Peter Lawrey, Java performance expert. +- [Randy Shoup](https://twitter.com/randyshoup) - Stitch Fix VP Engineering, speaker, JavaOne Rock Star. +- [Reza Rahman](https://twitter.com/reza_rahman) - Java EE/GlassFish/WebLogic evangelist, author, speaker, open source hacker. +- [Sander Mak](https://twitter.com/Sander_Mak) - Java Champion, author. +- [Simon Maple](https://twitter.com/sjmaple) - Java Champion, VirtualJUG founder, LJC leader, RebelLabs author. +- [Spencer Gibb](https://twitter.com/spencerbgibb) - Software Engineer, Dad, Geek, Co-founder and Lead of Spring Cloud Core @pivotal. +- [Stephen Colebourne](https://bsky.app/profile/jodastephen.bsky.social) - Java Champion, speaker. +- [Trisha Gee](https://twitter.com/trisha_gee) - Java Champion and speaker. +- [Venkat Subramaniam](https://twitter.com/venkat_s) - Author, University of Houston professor, MicroSoft MVP award recipient, JavaOne Rock Star, Java Champion. +- [Vlad Mihalcea](https://twitter.com/vlad_mihalcea) - Java Champion working on Hypersistence Optimizer, database aficionado, author of High-Performance Java Persistence book. + +### Websites + +_Sites to read._ + +- [Baeldung](https://www.baeldung.com) +- [Dzone](https://dzone.com) +- [InfoQ](https://www.infoq.com) +- [java.libhunt.com](https://java.libhunt.com) +- [Java, SQL, and jOOQ](https://blog.jooq.org) +- [Java.net](https://community.oracle.com/community/java) +- [Javalobby](https://dzone.com/java-jdk-development-tutorials-tools-news) +- [JavaWorld](https://www.javaworld.com) +- [JAXenter](https://jaxenter.com) +- [RebelLabs](https://zeroturnaround.com/rebellabs) +- [TheServerSide.com](https://www.theserverside.com) +- [Vanilla Java](https://vanilla-java.github.io) diff --git a/mise.toml b/mise.toml new file mode 100644 index 00000000..858588e5 --- /dev/null +++ b/mise.toml @@ -0,0 +1,2 @@ +[tools] +java = "temurin"