java的动态代理模式简单实例

java动态代理模式是一种常用的模式，Spring的AOP原理也是基于此。简单实例步骤如下：

第一：编写接口

package com.service;

public interface UserService {
 public void say();
 public void hello();
}

 

第二：接口的实现类

package com.service.impl;

import com.service.UserService;

public class UserServiceBean implements UserService {
 
 private String name;
 
 public UserServiceBean(){};
 
 public UserServiceBean(String name){
  this.name = name;
 }
 
 public void say() {
  System.out.println("恭喜你来到此地...");
  this.hello();
 }

 public void hello() {
  System.out.println("欢迎您！");
 }

 public String getName() {
  return name;
 }
 
}
第三：代理工厂

package com.aop;

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

import com.service.impl.UserServiceBean;

public class UserServiceProxy implements InvocationHandler {
 private Object targetObject;
 public Object createProxyIntance(Object targetObject){
  this.targetObject = targetObject;
  return Proxy.newProxyInstance(this.targetObject.getClass().getClassLoader(),
    this.targetObject.getClass().getInterfaces(), this);
 }
 
 public Object invoke(Object proxy, Method method, Object[] args)
   throws Throwable {
  UserServiceBean bean = (UserServiceBean) this.targetObject;
  Object obj = null;
  if(bean.getName() != null){
   if(bean.getName().equals("wuq")){
    obj = method.invoke(this.targetObject, args);
   }else{
    System.out.println("您没有操作权限！");
   }
  }else{
   System.out.println("您没有操作权限！");
  }
  return obj;
 }
}
第四：测试类

package com.test;

import com.aop.UserServiceProxy;
import com.service.UserService;
import com.service.impl.UserServiceBean;

public class UserServiceTest {

 public static void main(String[] args) {
  UserServiceProxy pro = new UserServiceProxy();
  UserServiceBean bean = new UserServiceBean("wuq");
  UserService se = (UserService) pro.createProxyIntance(bean);
  se.say(); 
 }

}