diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..c2629dc
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,22 @@
+# Eclipse
+.project
+.classpath
+.settings/
+ 
+# Idea
+.idea/
+*.iml
+*.iws
+*.ipr
+ 
+# Maven
+target/
+ 
+# Build
+out/
+build/
+bin/
+
+ 
+# Others
+*.log
diff --git a/README.md b/README.md
index 34829ed..a3aa7a2 100644
--- a/README.md
+++ b/README.md
@@ -15,4 +15,5 @@ Find more detail at:
 * [Create Immutable Lists In Java 9 By Static Factory Methods](https://howtoprogram.xyz/2017/09/24/java-9-create-immutable-lists-static-factory-method/)
 * [Java 9 Example With Maven And JUnit 5](https://howtoprogram.xyz/2017/09/23/java-9-maven-junit-5-example/)
 * [Copy Streams In Java 9 With The InputStream.transferTo() Method](https://howtoprogram.xyz/2017/10/01/java-9-inputstream-transferto-copy-streams/)
-* [Java 9 HTTP 2 Client API Example](https://howtoprogram.xyz/2017/10/19/java-9-http-2-client-api-example/)
\ No newline at end of file
+* [Java 9 HTTP 2 Client API Example](https://howtoprogram.xyz/2017/10/19/java-9-http-2-client-api-example/)
+* [Create An Immutable Set In Java 9 By Static Factory Methods](https://howtoprogram.xyz/2017/12/31/create-immutable-set-java-9-static-factory-methods/)
\ No newline at end of file
diff --git a/java9-language-features-examples/README.md b/java9-language-features-examples/README.md
index 1d04fce..fb3d14e 100644
--- a/java9-language-features-examples/README.md
+++ b/java9-language-features-examples/README.md
@@ -12,6 +12,7 @@ Demonstration for:
 
 [Java 9 HTTP 2 Client API Example](https://howtoprogram.xyz/2017/10/19/java-9-http-2-client-api-example/)
 
+[Create An Immutable Set In Java 9 By Static Factory Methods](https://howtoprogram.xyz/2017/12/31/create-immutable-set-java-9-static-factory-methods/)
 
 
 ## Prerequisites:
diff --git a/java9-language-features-examples/src/test/java/com/howtoprogram/java9ex/Java9SetFactoryMethodTest.java b/java9-language-features-examples/src/test/java/com/howtoprogram/java9ex/Java9SetFactoryMethodTest.java
new file mode 100644
index 0000000..d1df2ba
--- /dev/null
+++ b/java9-language-features-examples/src/test/java/com/howtoprogram/java9ex/Java9SetFactoryMethodTest.java
@@ -0,0 +1,93 @@
+package com.howtoprogram.java9ex;
+
+import org.junit.jupiter.api.Test;
+
+import java.io.*;
+import java.util.*;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+
+public class Java9SetFactoryMethodTest {
+
+
+    @Test
+    public void testImmutableSetJava9() {
+        Set<String> japanNoodles = Set.of("Ramen", "Yakisoba", "Udon", "Soba", "Somen");
+        assertEquals(5, japanNoodles.size());
+    }
+
+    @Test
+    public void testImmutableSetNotModified() {
+        Set<String> japanNoodles = Set.of("Ramen", "Yakisoba", "Udon", "Soba", "Somen");
+        assertEquals(5, japanNoodles.size());
+        assertThrows(UnsupportedOperationException.class, () -> {
+            // Add more element
+            japanNoodles.add("Negi");
+            // Remove element
+            japanNoodles.remove(1);
+        });
+
+    }
+
+    @Test
+    public void testImmutableSetNullAttempts() {
+        assertThrows(NullPointerException.class, () -> {
+            Set<String> stringList = Set.of(null);
+        });
+
+    }
+
+    @Test
+    public void testImmutableSetRejectDupplicates() {
+        assertThrows(IllegalArgumentException.class, () -> {
+            Set<?> teaSet = Set.of("Shincha", "Aki Bancha", "Hojicha", "Hojicha");
+        });
+
+    }
+
+    @Test
+    public void testImmutableSetMutableElements() {
+
+        Map<Integer, String> noodleToppingsMap = new HashMap<>();
+        noodleToppingsMap.put(1, "Negi");
+        noodleToppingsMap.put(2, "Tamago");
+        noodleToppingsMap.put(3, "Nori");
+
+        Map<Integer, String> japanTeaMap = new HashMap<>();
+        japanTeaMap.put(1, "Ryokucha");
+        japanTeaMap.put(2, "Yamecha");
+        japanTeaMap.put(3, "Ujicha");
+
+        List<Map<Integer, String>> choices = List.of(noodleToppingsMap, japanTeaMap);
+
+        assertEquals(3, choices.get(0).size());
+
+        //Add more elements to the mutable element of the List
+        noodleToppingsMap.put(3, "Tsuyu");
+        choices.get(0).put(4, "Aracha");
+
+        assertEquals(4, choices.get(0).size());
+
+    }
+
+    @Test
+    public void testImmutableSetSerializable() throws IOException {
+        Set<String> drinks = Set.of("Gyokuro", "Tamaryokucha", "Kamairicha");
+        //serialize the list
+        ObjectOutputStream oos = new ObjectOutputStream(System.out);
+        oos.writeObject(drinks);
+
+        //create a list of non-serializable objects
+        List<OutputStream> outputStreamList = List.of(new ByteArrayOutputStream(),
+                new PrintStream(System.out));
+
+        assertThrows(NotSerializableException.class, () -> {
+
+                    oos.writeObject(outputStreamList);
+                }
+        );
+    }
+
+}