//log4j的使用见文章“log4j介绍”
import org.apache.log4j.Logger;
public class Person {
 private Logger logger = Logger.getLogger(Person.class);
 public void sleep(){
  logger.info(“开始执行时间:“ + new Date());
  System.out.println("睡觉中");
  logger.info(“执行结束时间:” + new Date());
 }
 public void eating(){
  logger.info("开始执行时间:“ + new Date()");
  System.out.println("正在吃饭中");
  logger.info("“执行结束时间:” + new Date()");
 }
}

public interface IPerson {
 public abstract void sleep();
 public abstract void eating();
}

public class Person implements IPerson {
 public void sleep(){
  System.out.println("睡觉中");
 }
 public void eating(){
  System.out.println("正在吃饭中");
 }
}

import org.apache.log4j.Logger;
public class PersonProxy implements IPerson {
 private IPerson person;
 private Logger logger = Logger.getLogger(PersonProxy.class);
 public PersonProxy(IPerson person) {
  this.person = person;
 }
 public void eating() {
  logger.info("开始执行时间:“ + new Date()");
  person.eating();
  logger.info("“执行结束时间:” + new Date()");
 }
 public void sleep() {
  logger.info("开始执行时间:“ + new Date()");
  person.sleep();
  logger.info("“执行结束时间:” + new Date()");
 }
}

package com.aptech.aop2;
public class PersonTest {
 public static void main(String[] args) {
  IPerson proxy = new PersonProxy(new Person());
  proxy.eating();
  proxy.sleep();
 }
}

public class DynaProxyHandler implements InvocationHandler {
 private Logger logger = Logger.getLogger(DynaProxyHandler.class);
 private Object target;
 //被代理对象
 public void setTarget(Object target) {
  this.target = target;
 }
 public Object invoke(Object proxy, Method method, Object[] args)
               throws Throwable {
  logger.info("执行开始时间:" + new Date());
  Object result = method.invoke(target, args);
  logger.info("执行结束时间:" + new Date());
  return result;
  //返回method执行结果
 }
}

import java.lang.reflect.Proxy;
public class DynaProxyFactory {
 //obj为被代理对象
 public static Object getProxy(Object obj){
  DynaProxyHandler handler = new DynaProxyHandler();
  handler.setTarget(obj);
  return Proxy.newProxyInstance(obj.getClass().getClassLoader(), obj.getClass().getInterfaces(), handler);
 }
}

public class PersonTest {
 public static void main(String[] args) {
  IPerson person = (IPerson) DynaProxyFactory.getProxy(new Person());
  //返回代理类,代理类是JVM在内存中动态创建的,该类实现传入的接口数组的全部接口(的全部方法).
  person.eating();
  person.sleep();
 }
}