InvocationHandler接口- public interface InvocationHandler{
- public Object invoke(Object proxy,Method method,Object[] args)throws Throwable
- }
复制代码参数说明: Object proxy:被代理的对象 Method method:要调用的方法 Object args[]:方法调用时所需要的参数
Proxy类 Proxy类是专门完成代理的操作类,可以通过此类为一个或多个接口动态地生成实现类,此类提供了如下的操作方法:- public static Object newProxyInstance(ClassLoader loader,
- Class<?>[] interfaces,
- InvocationHandler h)
- throws IllegalArgumentException
复制代码 参数说明: ClassLoader loader:类加载器 Class<?>[] interfaces:得到全部的接口 InvocationHandler h:得到InvocationHandler接口的子类实例 动态代理:- package com.itmyhome;
-
- import java.lang.reflect.InvocationHandler;
- import java.lang.reflect.Method;
- import java.lang.reflect.Proxy;
-
- interface IHello{ //定义接口
- public void sayHello();
- }
- class HelloImpl implements IHello{
-
- @Override
- public void sayHello() {
- // TODO Auto-generated method stub
- System.out.println("hello itmyhome");
- }
- }
- class MyInvocationHandler implements InvocationHandler{
-
- private Object obj; //真实主题类
- public Object bind(Object obj){
- this.obj = obj;
- return Proxy.newProxyInstance(obj.getClass().getClassLoader(), obj.getClass().getInterfaces(), this);
- }
- @Override
- public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
- System.out.println("***before***");
- Object temp = method.invoke(obj, args);
- System.out.println("***after***");
- return temp;
- }
- }
-
- public class T {
- public static void main(String[] args) throws Exception{
- IHello h = (IHello)new MyInvocationHandler().bind(new HelloImpl());
- h.sayHello();
- }
- }
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