JDK8 动态代理，及性能测试

先说结论：

1，动态代理，继承Proxy，类实现接口。但需要反射。动态代理类，会被缓存。但反射仍慢。

2，100M次性能结果：

testDynamicProxyPerformance=73277     //先newInstance(),再方法的反射调用。

testDynamicProxyFilePerformance=1639 //没有newInstance(),只有方法的反射调用。

testStaticProxyPerformance=38

 

过程：

 

1，接口。

 

package time.river.proxy;
public interface ITarget{
	public void doA(int age);
	public void doB(String name, int age);
	public int getAge();
	public void setAge(int age);
}

 

 

 2，目标类

 

 

package time.river.proxy;
public class MyTarget implements ITarget {
	private int age;
	@Override
	public void doA(int age) {
		System.out.println("doA.....,age=" + age);
	}
	@Override
	public void doB(String name, int age) {
		System.out.println("doB.....,name=" + name + ",age=" + age);
	}
	@Override
	public int getAge() {
		return age;
	}
	@Override
	public void setAge(int age) {
		this.age = age;
	}
}

 3，Handler

package time.river.proxy;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
public class MyHandler implements InvocationHandler {
	private Object targetObj;
	public MyHandler(Object targetObj) {
		this.targetObj = targetObj;
	}
	@Override
	public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
//		System.out.println("哥是代理------------------------------------");
		return method.invoke(targetObj, args);
	}
}

 4, 测试类

package time.river.proxy;
import java.io.FileOutputStream;
import java.lang.reflect.Proxy;
import sun.misc.ProxyGenerator;
public class Test {
	public static void main(String args[]) throws Exception{
//		testDynamicProxy();
//		createProxyClassFile();
//		testProxyFile();
		
		testDynamicProxyPerformance();
		testDynamicProxyFilePerformance();
		testStaticProxyPerformance();
	}

	private static void testDynamicProxy() throws Exception{
		MyTarget target = new MyTarget();
		ITarget proxy = (ITarget) Proxy.newProxyInstance(ITarget.class.getClassLoader(),
				new Class[] { ITarget.class }, new MyHandler(target));
//		proxy.doA(20);
//		proxy.doB("wnj", 20);
		proxy.setAge(20);
	}
	
	/**
	 * 生成的动态代理文件。使用jad反编译。
	 */
	private static void createProxyClassFile() throws Exception{
		String name = "DynamicProxy"; //生成的动态代理文件。
		//Proxy内部方法：ProxyGenerator.generateProxyClass。
		byte[] data = ProxyGenerator.generateProxyClass(name, new Class[] { ITarget.class });
		FileOutputStream out = new FileOutputStream(name + ".class");
		out.write(data);
		out.close();
	}
	public static void testProxyFile(){
		MyTarget target = new MyTarget(); 
		MyHandler handler = new MyHandler(target);
		DynamicProxy proxy = new DynamicProxy(handler);
//		proxy.doA(20);
//		proxy.doB("wnj", 20);
		proxy.setAge(20);
	}
	private static int cnt = 1000 * 1000 * 100;
	private static void testDynamicProxyPerformance() throws Exception{
		long s = System.currentTimeMillis();
		for (int i = 0; i < cnt; i++) {
			testDynamicProxy();
		}
		long e = System.currentTimeMillis();
		System.out.println("testDynamicProxyPerformance="+(e-s));
	}
	private static void testDynamicProxyFilePerformance() throws Exception{
		long s = System.currentTimeMillis();
		for (int i = 0; i < cnt; i++) {
			testProxyFile();
		}
		long e = System.currentTimeMillis();
		System.out.println("testDynamicProxyFilePerformance="+(e-s));
	}
	private static void testStaticProxyPerformance() throws Exception{
		long s = System.currentTimeMillis();
		for (int i = 0; i < cnt; i++) {
			testStaticProxy();
		}
		long e = System.currentTimeMillis();
		System.out.println("testStaticProxyPerformance="+(e-s));
	}
	public static void testStaticProxy(){
		MyTarget target = new MyTarget(); 
		StaticProxy proxy = new StaticProxy(target);
//		proxy.doA(20);
//		proxy.doB("wnj", 20);
		proxy.setAge(20);
	}
}

 5，动态代理类。保存到class文件，再用jad反编译。

package time.river.proxy;
import java.lang.reflect.*;
import time.river.proxy.ITarget;

/**
 * Test类createProxyClassFile()方法，生成的class文件。然后用jad反编译，再修改语法错误。
 */
public final class DynamicProxy extends Proxy implements ITarget {
	public DynamicProxy(InvocationHandler invocationhandler) {
		super(invocationhandler);
	}
	public final void setAge(int i) {
		try {
			super.h.invoke(this, m6, new Object[] { Integer.valueOf(i) });
			return;
		} catch (Error _ex) {
		} catch (Throwable throwable) {
			throw new UndeclaredThrowableException(throwable);
		}
	}
	public final boolean equals(Object obj) {
		try {
			return ((Boolean) super.h.invoke(this, m1, new Object[] { obj })).booleanValue();
		} catch (Error _ex) {
		} catch (Throwable throwable) {
			throw new UndeclaredThrowableException(throwable);
		}
		return false;
	}
	public final void doA(int i) {
		try {
			super.h.invoke(this, m3, new Object[] { Integer.valueOf(i) });
			return;
		} catch (Error _ex) {
		} catch (Throwable throwable) {
			throw new UndeclaredThrowableException(throwable);
		}
	}
	public final int getAge() {
		try {
			return ((Integer) super.h.invoke(this, m5, null)).intValue();
		} catch (Error _ex) {
		} catch (Throwable throwable) {
			throw new UndeclaredThrowableException(throwable);
		}
		return 0;
	}
	public final void doB(String s, int i) {
		try {
			super.h.invoke(this, m4, new Object[] { s, Integer.valueOf(i) });
			return;
		} catch (Error _ex) {
		} catch (Throwable throwable) {
			throw new UndeclaredThrowableException(throwable);
		}
	}
	public final int hashCode() {
		try {
			return ((Integer) super.h.invoke(this, m0, null)).intValue();
		} catch (Error _ex) {
		} catch (Throwable throwable) {
			throw new UndeclaredThrowableException(throwable);
		}
		return 0;
	}
	public final String toString() {
		try {
			return (String) super.h.invoke(this, m2, null);
		} catch (Error _ex) {
		} catch (Throwable throwable) {
			throw new UndeclaredThrowableException(throwable);
		}
		return "";
	}
	private static Method m6;
	private static Method m1;
	private static Method m3;
	private static Method m5;
	private static Method m4;
	private static Method m0;
	private static Method m2;
	static {
		try {
			m6 = Class.forName("time.river.proxy.ITarget").getMethod("setAge", new Class[] { Integer.TYPE });
			m1 = Class.forName("java.lang.Object").getMethod("equals",
					new Class[] { Class.forName("java.lang.Object") });
			m3 = Class.forName("time.river.proxy.ITarget").getMethod("doA", new Class[] { Integer.TYPE });
			m5 = Class.forName("time.river.proxy.ITarget").getMethod("getAge", new Class[0]);
			m4 = Class.forName("time.river.proxy.ITarget").getMethod("doB",
					new Class[] { Class.forName("java.lang.String"), Integer.TYPE });
			m0 = Class.forName("java.lang.Object").getMethod("hashCode", new Class[0]);
			m2 = Class.forName("java.lang.Object").getMethod("toString", new Class[0]);
		} catch (NoSuchMethodException nosuchmethodexception) {
			throw new NoSuchMethodError(nosuchmethodexception.getMessage());
		} catch (ClassNotFoundException classnotfoundexception) {
			throw new NoClassDefFoundError(classnotfoundexception.getMessage());
		}
	}
}

6，静态代理类

package time.river.proxy;
public class StaticProxy implements ITarget{
	private ITarget target;
	public StaticProxy(ITarget target) {
		super();
		this.target = target;
	}
	@Override
	public void doA(int age) {
	}
	@Override
	public void doB(String name, int age) {
	}
	@Override
	public int getAge() {
		return 0;
	}
	@Override
	public void setAge(int age) {
		target.setAge(age);
	}
}