package com.atguigu.proxy.dynamic;
public class Client {
public static void main(String[] args) {
    
	//創(chuàng)建目標(biāo)對(duì)象
	ITeacherDao target = new TeacherDao();
    
	//給目標(biāo)對(duì)象，創(chuàng)建代理對(duì)象, 可以轉(zhuǎn)成 ITeacherDao
    ITeacherDao proxyInstance = (ITeacherDao)newProxyFactory(target).getProxyInstance();
    
	// proxyInstance=class com.sun.proxy.$Proxy0 內(nèi)存中動(dòng)態(tài)生成了代理對(duì)象
	System.out.println("proxyInstance=" + proxyInstance.getClass());
    
	//通過(guò)代理對(duì)象，調(diào)用目標(biāo)對(duì)象的方法
	//proxyInstance.teach();
	proxyInstance.sayHello(" tom ");
	}
}

//接口
public interface ITeacherDao {
    
    void teach(); // 授課方法
    
	void sayHello(String name);
}

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

public class ProxyFactory {
    
	//維護(hù)一個(gè)目標(biāo)對(duì)象 , Object
	private Object target;
    
	//構(gòu)造器 ， 對(duì) target 進(jìn)行初始化
	public ProxyFactory(Object target) {
		this.target = target;
	}
    
//給目標(biāo)對(duì)象 生成一個(gè)代理對(duì)象
public Object getProxyInstance() {
//說(shuō)明
/*
public static Object newProxyInstance(ClassLoader loader,Class<?>[] interfaces,InvocationHandler h)
//1. ClassLoader loader ： 指定當(dāng)前目標(biāo)對(duì)象使用的類加載器, 獲取加載器的方法固定
//2. Class<?>[] interfaces: 目標(biāo)對(duì)象實(shí)現(xiàn)的接口類型，使用泛型方法確認(rèn)類型
//3. InvocationHandler h : 事情處理，執(zhí)行目標(biāo)對(duì)象的方法時(shí)，會(huì)觸發(fā)事情處理器方法, 會(huì)把當(dāng)前執(zhí)行的目標(biāo)對(duì)象方法作為參數(shù)傳入
*/
    return Proxy.newProxyInstance(target.getClass().getClassLoader(),target.getClass().getInterfaces(),
			new InvocationHandler() {
		@Override
		public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
			System.out.println("JDK 代理開(kāi)始~~");
			//反射機(jī)制調(diào)用目標(biāo)對(duì)象的方法
			Object returnVal = method.invoke(target, args);
			System.out.println("JDK 代理提交");
			return returnVal;
			}
		});
	}
}

public class TeacherDao implements ITeacherDao {
	@Override
	public void teach() {
   	 System.out.println(" 老師授課中.... ");
	}
    
	@Override
	public void sayHello(String name) {
        
	System.out.println("hello " + name);
        
	}
}