jdk与cglib的动态代理

JDK动态代理中包含一个类和一个接口: 
InvocationHandler接口: 
public interface InvocationHandler { 
public Object invoke(Object proxy,Method method,Object[] args) throws Throwable; 

参数说明: 
Object proxy:指被代理的对象。 
Method method:要调用的方法 
Object[] args:方法调用时所须要的参数 java

接口IFromServicespring

package com.test.service;

public interface IFromService {
    
    
    public void removeService(long serviveid) throws Exception;
    
    public void modifyService(long serviveid)throws Exception; 

}

接口实现类 FromServieImplide

package com.test.service;

public class FromServieImpl implements IFromService{

    @Override
    public void removeService(long serviveid) throws Exception {
        // TODO Auto-generated method stub
        System.out.println("模拟删除服务ID:"+serviveid);
        Thread.currentThread().sleep(20);
    }

    @Override
    public void modifyService(long serviveid) throws Exception {
        // TODO Auto-generated method stub
        System.out.println("模拟修改服务ID:"+serviveid);
        Thread.currentThread().sleep(40);
    }
    
    /**
     * 无接口实现类方法
     * @param obj
     * @throws InterruptedException
     */
    public void addService(Object obj) throws InterruptedException{
        System.out.println("模拟新增服务:"+obj);
        Thread.currentThread().sleep(40);
    }

}

jdk代理类 FromServiceProxy测试

package com.test.proxy;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.Date;

import com.test.utils.DateTimeUtil;

/**
 * jdk 动态代理
 * @author Administrator
 *
 */
public class FromServiceProxy implements InvocationHandler{
    private Object target;
    
    
    /**
     * 绑定委托类并返回代理类
     * @param target
     * @return
     */
    public Object bind(Object target){
        this.target=target;
        return Proxy.newProxyInstance(target.getClass().getClassLoader(),target.getClass().getInterfaces(),this);
    }
    
    /**
     * 调用
     */
    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        // TODO Auto-generated method stub
        Object result=null;
        Date stdate=new Date();
        System.out.println("监测 开始时间:"+DateTimeUtil.dateToStrOfDefaulfFormat(stdate));
        result=method.invoke(target, args);
        Date eddate=new Date();
        System.out.println("监测 结束时间:"+DateTimeUtil.dateToStrOfDefaulfFormat(eddate));
        System.out.println(method.getName()+" 执行耗时:"+(eddate.getTime()-stdate.getTime())+" ms");
        
        return result;
    }

}

测试 TestProxythis

package com.test.proxy;

import com.test.service.FromServieImpl;
import com.test.service.IFromService;

public class TestProxy {

    public static void main(String[] args) throws Exception {
        System.out.println("==============jdk proxy=================");
        FromServiceProxy proxy=new FromServiceProxy();
        IFromService service=(IFromService) proxy.bind(new FromServieImpl());
        service.removeService(123);
        service.modifyService(123);  
    }
}

输出以下:spa

==============jdk proxy=================
监测 开始时间:2016-03-24 13:25:48
模拟删除服务ID:123
监测 结束时间:2016-03-24 13:25:48
removeService 执行耗时:54 ms
监测 开始时间:2016-03-24 13:25:48
模拟修改服务ID:123
监测 结束时间:2016-03-24 13:25:48
modifyService 执行耗时:41 ms

 

Cglib动态代理 
JDK的动态代理机制只能代理实现了接口的类,而不能实现接口的类就不能实现JDK的动态代理,cglib是针对类来实现代理的,他的原理是对指定的目标类生成一个子类,并覆盖其中方法实现加强,但由于采用的是继承,因此不能对final修饰的类进行代理。 代理

 

cglib代理 FromServiceCglibProxycode

package com.test.proxy;

import java.lang.reflect.Method;
import java.util.Date;

import org.springframework.cglib.proxy.Enhancer;
import org.springframework.cglib.proxy.MethodInterceptor;
import org.springframework.cglib.proxy.MethodProxy;

import com.test.utils.DateTimeUtil;

/**
 * cglib  动态代理
 * @author Administrator
 *
 */
public class FromServiceCglibProxy implements MethodInterceptor{
    
    private Object target;
    
    /**
     * 建立代理对象
     * @param target
     * @return
     */
    public Object getInstance(Object target){
        this.target=target;
        Enhancer enhancer=new Enhancer();
        enhancer.setSuperclass(this.target.getClass());
        enhancer.setCallback(this);
        return enhancer.create();
    }

    @Override
    public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
        Date stdate=new Date();
        System.out.println("监测 开始时间:"+DateTimeUtil.dateToStrOfDefaulfFormat(stdate));
        proxy.invokeSuper(obj, args);
        Date eddate=new Date();
        System.out.println("监测 结束时间:"+DateTimeUtil.dateToStrOfDefaulfFormat(eddate));
        System.out.println(method.getName()+" 执行耗时:"+(eddate.getTime()-stdate.getTime())+" ms");
        return null;
    }

}

测试类 TestProxyorm

package com.test.proxy;

import com.test.service.FromServieImpl;
import com.test.service.IFromService;

public class TestProxy {

    public static void main(String[] args) throws Exception {
 
        System.out.println("==============cglib proxy=================");
        FromServiceCglibProxy cglib=new FromServiceCglibProxy();
        FromServieImpl serviceImpl=(FromServieImpl) cglib.getInstance(new FromServieImpl());
        serviceImpl.addService("entity");
    }
}

输出以下:对象

==============cglib proxy=================
监测 开始时间:2016-03-24 13:25:48
模拟新增服务:entity
监测 结束时间:2016-03-24 13:25:48
addService 执行耗时:65 ms
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