jdk 動態代理 兩種方法實現

方法一: 自己實現invocationHandler

package com.czh.Utils;

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

public class proxy_class<T> implements InvocationHandler {
    private  Class<T> target_class;

    public proxy_class(Class<T> target_class) {
        this.target_class = target_class;
    }


    public Object  newInstance () {
        return Proxy.newProxyInstance(target_class.getClassLoader(),target_class.getInterfaces(),this);
    }

    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        System.out.println("這是動態代理實現類!");
        method.invoke(target_class.newInstance(),args);
        return null;
    }

}

方法二 :

package com.czh.Utils;

import com.czh.domain.impl.userDaoimpl;
import com.czh.domain.userDao;
import com.sun.deploy.net.proxy.ProxyHandler;
import org.junit.Test;

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

public class jdkpoxy {
    public static void main(String[] args) {
        userDao UD = new userDaoimpl();
       /* userDao proxy =(userDao) new Proxy.getInvocationHandler();*/
        /*匿名內部類  實現*/
        userDao proxy = (userDao)Proxy.newProxyInstance(jdkpoxy.class.getClassLoader(),
              UD.getClass().getInterfaces(),
              new InvocationHandler() {
                  @Override
                  public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                      System.out.println("系統執行前:"+System.currentTimeMillis());
                      return method.invoke(UD, args);
                  }
              });
        proxy.eat("小明!");
        proxy.run();
    }
    /*測試  方法一  實現類*/
    @Test
    public  void  demo2(){
        proxy_class<userDaoimpl> userDaoimplproxy_class = new proxy_class<>(userDaoimpl.class);
        userDao o = (userDao)userDaoimplproxy_class.newInstance();
        o.eat("王雪雪");
        o.run();
    }

}