Proxy.newProxyInstance 理解

1.准备接口

interface Animals {
    fun sounds(name:String):String
    fun eat(name: String):String
}

2.准备实现类

class Dog :Animals {
    override fun sounds(name: String): String {
        println("$name 再叫")
        return "汪汪汪"
    }


    override fun eat(name: String): String {
        println("$name 再吃" )
        return "muniangmuniang"
    }
}

3.准备代理 及 Main函数

fun main() {
    val dog: Dog = Dog()


    val proxy = Proxy.newProxyInstance(
        dog.javaClass.classLoader, dog.javaClass.interfaces
    ) { proxy, method, args ->
        println(method.name)
        args?.forEach {
            println(it.toString())
        }
        println("open")
        method.invoke(dog, args[0])
        println("stop")
        null
    } as Animals

    proxy.sounds("张三")
    proxy.eat("lisi")
    println("xxx")




}

END 附上打印输出控制台

sounds
张三
open
张三 再叫
stop
eat
lisi
open
lisi 再吃
stop
xxx

Process finished with exit code 0

EXTRA再来点额外的。

public  void main2() {
        final Animals dog=new Dog();
        //com.example.learnkt.proxy.Dog is not an interface  ERROR 下面这个是执行不了的
        Animals animals= (Animals) Proxy.newProxyInstance(Dog.class.getClassLoader(), new Class[]{Dog.class}, new InvocationHandler() {
            @Override
            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {

                method.invoke(dog,args[0]);

                return null;
            }
        });

        Animals animals2= (Animals) Proxy.newProxyInstance(Animals.class.getClassLoader(), new Class[]{Animals.class}, new InvocationHandler() {
            @Override
            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {

                method.invoke(dog,args[0]);

                return null;
            }
        });

//        animals.eat("baba");  //ERROR
        animals2.sounds("hhsx");
    }