【Java SE】动态代理

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

public class SimpleDynamicProxy {
//    public static void consumer(Interface2 iface){
//        iface.doSth2();
//        iface.sthElse2("boboboo");
//    }
    public static void main(String[] args) {
        //1
        RealObject ro = new RealObject();
//        consumer(ro);
        //2
        Interface2 proxy =
                (Interface2) Proxy.newProxyInstance
                    (ro.getClass().getClassLoader(),
                    new Class[]{Interface.class, Interface2.class},
                    new DynamicProxyHandle(ro));
//        consumer(proxy);
        proxy.doSth2();
        proxy.sthElse2("hello world!");
        
        Interface2 proxy2 =
                (Interface2) Proxy.newProxyInstance
                    (ro.getClass().getClassLoader(),
                    new Class[]{Interface2.class},//如果这个参数不同,handle.invoke()会识别为两不同的proxy($Proxy0,$Proxy1)
//                    new Class[]{Interface.class, Interface2.class},
                    new DynamicProxyHandle(ro));
        proxy2.doSth2();
        ro.setStr("better world!");//有影响
        ro = null;//无影响    因为将引用置空并不能影响对象本身的状态??
        proxy2.doSth2();
        proxy2.sthElse2("hello world!");
    }
}
class DynamicProxyHandle implements InvocationHandler{
    private Object proxied;//被代理对象，不表达对象   此例即  RealObject
    public DynamicProxyHandle(Object proxied){
        this.proxied = proxied;
    }
    @Override//为什么要传proxy？针对不同proxy可能会有不同处理
    public Object invoke(
            Object proxy, Method method, Object[] args//args
            ) throws Throwable {
        System.out.println(proxy.getClass().getSimpleName());
        /*!在这里进行更多操作*/
//        System.out.println("do More Before");
        String ret = (String) method.invoke(proxied,args);
        System.out.println("return -> "+ret);
//        System.out.println("do More After");
        return null;
    }
    
}

interface Interface{
    String doSth();
    void sthElse(String arg);
}
interface Interface2{
    String doSth2();
    void sthElse2(String arg);
}
class RealObject implements Interface,Interface2{

    private String str = "hello world!";
    public void setStr(String str){
        this.str = str;
    }
    @Override
    public String doSth() {
        // TODO Auto-generated method stub
        System.out.println("do sth "+str);
        return "return obj";
    }

    @Override
    public void sthElse(String arg) {
        // TODO Auto-generated method stub
        System.out.println("do else "+arg);
    }

    @Override
    public String doSth2() {
        // TODO Auto-generated method stub
        System.out.println("do sth2 "+str);
        return "return obj2";
    }

    @Override
    public void sthElse2(String arg) {
        // TODO Auto-generated method stub
        System.out.println("do else2 "+arg);
    }
    
}