Add java-dynamic-proxy

java-dynamic-proxy/src/com/codekk/java/test/dynamicproxy/Main.java

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+package com.codekk.java.test.dynamicproxy;
+
+import java.lang.reflect.Method;
+import java.lang.reflect.Proxy;
+
+import com.codekk.java.test.dynamicproxy.util.ProxyUtils;
+
+/**
+ * Dynamic Proxy Demo
+ * 
+ * @author [email protected]
+ */
+public class Main {
+    public static void main(String[] args) {
+
+        TimingInvocationHandler timingInvocationHandler = new TimingInvocationHandler(new OperateImpl());
+        Operate operate = (Operate)(Proxy.newProxyInstance(Operate.class.getClassLoader(), new Class[] {Operate.class},
+                timingInvocationHandler));
+
+        // call proxy instance method
+        operate.operateMethod1();
+        System.out.println();
+        operate.operateMethod2();
+        System.out.println();
+        operate.operateMethod3();
+
+        // print info of proxy class
+        System.out.println("proxy class is: " + operate.getClass().getName());
+        System.out.println("\r\nsuper class of proxy class is: " + operate.getClass().getSuperclass().getName());
+        System.out.println("\r\ninterfaces of proxy class are: ");
+        for (Class inter : operate.getClass().getInterfaces()) {
+            System.out.println("\t" + inter.getName());
+        }
+        System.out.println("\r\nmethods of proxy class are: ");
+        for (Method method : operate.getClass().getMethods()) {
+            System.out.println("\t" + method.getName());
+        }
+
+        // save proxy class to root of this project, you can use jd-gui to see content of the saved file
+        String saveFileName = "$Proxy0.class";
+        ProxyUtils.saveProxyClass(saveFileName, operate.getClass().getSimpleName(), operate.getClass().getInterfaces());
+        System.out.println("\r\nContent of " + operate.getClass().getSimpleName() + ".class has saved to file "
+                + saveFileName + " at root of this project");
+    }
+}

java-dynamic-proxy/src/com/codekk/java/test/dynamicproxy/Operate.java

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+package com.codekk.java.test.dynamicproxy;
+
+/**
+ * Operate Interface, Proxy Class need to implements this
+ * 
+ * @author [email protected]
+ */
+public interface Operate {
+
+    public void operateMethod1();
+
+    public void operateMethod2();
+
+    public void operateMethod3();
+}

java-dynamic-proxy/src/com/codekk/java/test/dynamicproxy/OperateImpl.java

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+package com.codekk.java.test.dynamicproxy;
+
+/**
+ * Proxy class, implements {@link Operate}
+ * 
+ * @author [email protected]
+ */
+public class OperateImpl implements Operate {
+
+    @Override
+    public void operateMethod1() {
+        System.out.println("Invoke operateMethod1");
+        sleep(110);
+    }
+
+    @Override
+    public void operateMethod2() {
+        System.out.println("Invoke operateMethod2");
+        sleep(120);
+    }
+
+    @Override
+    public void operateMethod3() {
+        System.out.println("Invoke operateMethod3");
+        sleep(130);
+    }
+
+    private static void sleep(long millSeconds) {
+        try {
+            Thread.sleep(millSeconds);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+    }
+}

java-dynamic-proxy/src/com/codekk/java/test/dynamicproxy/TimingInvocationHandler.java

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+package com.codekk.java.test.dynamicproxy;
+
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.Method;
+
+/**
+ * InvocationHandler to timing proxy class
+ * 
+ * @author [email protected]
+ */
+public class TimingInvocationHandler implements InvocationHandler {
+
+    private Object target;
+
+    public TimingInvocationHandler() {}
+
+    public TimingInvocationHandler(Object target) {
+        this.target = target;
+    }
+
+    @Override
+    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
+        long start = System.currentTimeMillis();
+        Object obj = method.invoke(target, args);
+        System.out.println(method.getName() + " cost time is:" + (System.currentTimeMillis() - start));
+        return obj;
+    }
+}

java-dynamic-proxy/src/com/codekk/java/test/dynamicproxy/util/ProxyUtils.java

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+package com.codekk.java.test.dynamicproxy.util;
+
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+import sun.misc.ProxyGenerator;
+
+/**
+ * Utils of proxy
+ * 
+ * @author [email protected]
+ * @thx to <a href="http://rejoy.iteye.com/blog/1627405">Rejoy's Blog</a>
+ */
+public class ProxyUtils {
+
+    /**
+     * Save proxy class to path
+     * 
+     * @param path path to save proxy class
+     * @param proxyClassName name of proxy class
+     * @param interfaces interfaces of proxy class
+     * @return
+     */
+    public static boolean saveProxyClass(String path, String proxyClassName, Class[] interfaces) {
+        if (proxyClassName == null || path == null) {
+            return false;
+        }
+
+        // get byte of proxy class
+        byte[] classFile = ProxyGenerator.generateProxyClass(proxyClassName, interfaces);
+        FileOutputStream out = null;
+        try {
+            out = new FileOutputStream(path);
+            out.write(classFile);
+            out.flush();
+            return true;
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            try {
+                out.close();
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+        return false;
+    }
+}