feat:中间件、springcloud等案例

Author: KayCheung

java-example/java-algorithm-example/pom.xml

@@ -3,6 +3,18 @@
          xmlns="http://maven.apache.org/POM/4.0.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
     <modelVersion>4.0.0</modelVersion>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
     <parent>
         <groupId>com.housaire</groupId>
         <artifactId>java-example</artifactId>

java-example/java-algorithm-example/src/main/java/com/housaire/App.java

@@ -3,6 +3,7 @@
 import java.sql.Timestamp;
 import java.text.SimpleDateFormat;
 import java.util.Date;
+import java.util.TreeMap;
 
 /**
  * Hello world!
@@ -48,7 +49,7 @@ public void sayHello()
 
     public static void main(String[] args) throws CloneNotSupportedException
     {
-        A a = new A(10);
+        /*A a = new A(10);
         a.b = 5;
         a. c = -19;
         A b = a.clone();
@@ -70,7 +71,12 @@ public static void main(String[] args) throws CloneNotSupportedException
         System.out.println(a);
 
         System.out.println(a.getClass().getClassLoader());
-        System.out.println(String.class.getClassLoader());
+        System.out.println(String.class.getClassLoader());*/
+
+
+        Integer i1 = new Integer(1);
+        Integer i2 = new Integer(2);
+        System.out.println("Integer == " + (i1 == i2));
 
     }
 

java-example/java-algorithm-example/src/main/java/com/housaire/App1.java

@@ -0,0 +1,64 @@
+package com.housaire;
+
+import java.util.concurrent.*;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * Created by kay on 2019/12/7.
+ */
+public class App1 {
+
+    private static final int COUNT_BITS = Integer.SIZE - 3;
+    private static final int CAPACITY   = (1 << COUNT_BITS) - 1;
+    private static final int RUNNING    = -1 << COUNT_BITS;
+    private static final int SHUTDOWN   =  0 << COUNT_BITS;
+    private static final AtomicInteger ctl = new AtomicInteger(ctlOf(RUNNING, 0));
+    private static int runStateOf(int c)     { return c & ~CAPACITY; }
+    private static int workerCountOf(int c)  { return c & CAPACITY; }
+    private static int ctlOf(int rs, int wc) { return rs | wc; }
+
+    private static boolean isRunning(int c) {
+        return c < SHUTDOWN;
+    }
+
+    public static void main(String[] args) throws Exception {
+        System.out.println("runStateOf:  " + runStateOf(ctl.get()));
+        System.out.println("SHUTDOWN:  " + SHUTDOWN);
+        System.out.println("workerCountOf:  " + workerCountOf(ctl.get()));
+        System.out.println("CAPACITY:  " + CAPACITY);
+        System.out.println("isRunning:  " + isRunning(ctl.get()));
+
+        ExecutorService cachedThreadPool = Executors.newCachedThreadPool();
+        cachedThreadPool.execute(new Runnable() {
+            @Override
+            public void run() {
+                System.out.println("111");
+            }
+        });
+
+        final SynchronousQueue queue = new SynchronousQueue();
+
+        CountDownLatch cdl = new CountDownLatch(1);
+
+        cachedThreadPool.execute(new Runnable() {
+            @Override
+            public void run() {
+                try {
+                    cdl.countDown();
+                    System.out.println("Queue->take: " + queue.take());
+                    System.out.println("Queue->take: " + queue.take());
+                } catch (InterruptedException e) {
+                    e.printStackTrace();
+                }
+            }
+        });
+
+        cdl.await();
+        System.out.println("Queue->offer:  " + queue.offer("abc"));
+        queue.put("321");
+        System.out.println("finished");
+
+        cachedThreadPool.shutdown();
+    }
+
+}

java-example/java-algorithm-example/src/main/java/com/housaire/InnerClassDemo.java

@@ -0,0 +1,20 @@
+package com.housaire;
+
+/**
+ * Created by kay on 2019/12/2.
+ */
+public class InnerClassDemo {
+
+    public void sayHello() {
+        System.out.println("Out say hello");
+    }
+
+    class StaticInnerClass {
+
+        public void studing() {
+            sayHello();
+        }
+
+    }
+
+}

java-example/java-algorithm-example/src/main/java/com/housaire/IntReverse.java

@@ -0,0 +1,21 @@
+package com.housaire;
+
+/**
+ * Created by kay on 2019/12/12.
+ */
+public class IntReverse {
+
+    public static int reverse(int num) {
+        int rev = 0;
+        while (num != 0) {
+            rev = rev * 10 + num % 10;
+            num /= 10;
+        }
+        return rev;
+    }
+
+    public static void main(String[] args) {
+        System.out.println(reverse(-199));
+    }
+
+}

java-example/java-algorithm-example/src/main/java/com/housaire/RandomRedPacket.java

@@ -25,13 +25,20 @@ public static void main(String[] args)
         float amount = 10;
         int num = 900;
         double total = 0;
+        int a = 0, b = 0, c = 0;
         for (int i = num; i > 0; i--)
         {
             double money = RandomRedPacket.getRandomMoney(i, amount);
             total += money;
             amount = (float) (amount - money);
             System.out.println("第" + (num - i) + "个红包：" + money);
+            if (money == 0.01) a++;
+            else if(money == 0.02) b++;
+            else c++;
         }
+        System.out.println("得到 0.01 元红包的人数为：" + a);
+        System.out.println("得到 0.02 元红包的人数为：" + b);
+        System.out.println("得到 0.03 元红包的人数为：" + c);
         System.out.println(total);
     }
 

java-example/java-algorithm-example/src/main/java/com/housaire/SafeListener.java

@@ -0,0 +1,49 @@
+package com.housaire;
+
+/**
+ * Created by kay on 2019/12/2.
+ */
+public class SafeListener {
+    private final EventListener listener;
+
+    private SafeListener() {
+        listener = new EventListener() {
+            @Override
+            public void onEvent(Event e) {
+                doSomething(e);
+        }
+        };
+    }
+
+    public static SafeListener newInstance(EventSource source) {
+        SafeListener safe = new SafeListener();
+        source.registerListener(safe.listener);
+        return safe;
+    }
+
+    void doSomething(Event e) {
+        System.out.println("hi event " + e);
+    }
+
+    interface EventSource {
+        void registerListener(EventListener e);
+    }
+
+    interface EventListener {
+        void onEvent(Event e);
+    }
+
+    interface Event {
+    }
+
+    public static void main(String[] args) {
+        SafeListener listener = SafeListener.newInstance(new EventSource() {
+            @Override
+            public void registerListener(EventListener e) {
+                    e.onEvent(new Event() {
+                });
+            }
+        });
+    }
+
+}

java-example/java-algorithm-example/src/main/java/com/housaire/cache/LRUCache.java

@@ -0,0 +1,39 @@
+package com.housaire.cache;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+/**
+ * Created by kay on 2019/11/28.
+ */
+public class LRUCache extends LinkedHashMap {
+
+    private int maxSize;
+
+    public LRUCache(int maxSize)
+    {
+        super(0, 0.75f, true);
+        this.maxSize = maxSize;
+    }
+
+    @Override
+    protected boolean removeEldestEntry(Map.Entry eldest) {
+        return this.size() > maxSize;
+    }
+
+
+    public static void main(String[] args) {
+        LRUCache lruCache = new LRUCache(10);
+        for (int i = 0; i < 10; i++)
+        {
+            lruCache.put(i, i);
+        }
+        System.out.println(lruCache);
+
+        lruCache.get(0);
+        lruCache.put(11, 11);
+        System.out.println(lruCache);
+    }
+
+
+}

java-example/java-algorithm-example/src/main/java/com/housaire/list/linked/LinkedListDivideEqually.java

@@ -2,6 +2,9 @@
 
 /**
  * 链表三等份
+ * 设三个链表：   第一个每循环一次走一步
+ *              第二个每循环一次走两步
+ *              第三个每循环一次走三步
  */
 public class LinkedListDivideEqually
 {

java-example/java-classloader-example/src/main/java/com/housaire/ClassLoaderDemo.java

@@ -0,0 +1,19 @@
+package com.housaire;
+
+/**
+ * Created by kay on 2019/9/16.
+ */
+public class ClassLoaderDemo {
+
+    public static void main(String[] args) {
+        System.out.println(A.class);
+    }
+}
+
+class A {
+
+    static {
+        System.err.println("class A");
+    }
+
+}