java动态代理

1.简单接口

public interface Subject{
    Public void request();
}

 

2.被代理角色类

public class RealSubject implements Subject{
    public RealSubject(){}

    public void request(){
        System.out.println("Hello World");
    }
}

 

3.代理角色类

public class ProxySubject implements InvocationHandler{
    // 必须实现invocationHandle接口，因此就需要实现invoke接口方法
   private Object sub;

    public ProxySubject (){}

    public ProxySubject (Object obj){
        this.sub = obj;
    }

    public Object invoke(Object proxy,Method method,Object[] args) throws Throwable{
        method.invoke(sub,args);
        return null;
    }
}

 

4.客户端调用类

public class Client{
    public static void main(String srgs[]){
        RealSubject rs = new RealSubject();
        InvocantionHandle ds = new ProxySubject(rs);     // JAVA多态性
     Class cls = rs.getClass();

        Subject subject = (Subject) Proxy.newProxyInstance(cls.getClasssLoader,cls.getInterfaces(),ds);
        subject.request();
    }
}