代理模式

代理模式结构图

代码

public class ProxyTest {
    public static void main(String[] args) {
        Proxy proxy = new Proxy();
        proxy.Request();
    }
}
//抽象类
public abstract class Subject {
    public abstract void Request();
}
//被代理的对象
public class RealSubject extends Subject{
    @Override
    public void Request() {
        System.out.println("真实的请求");
    }
}
//代理对象
public class Proxy extends Subject{
    Subject subject;
    @Override
    public void Request() {
        if (subject == null){
            subject = new RealSubject();
        }
        System.out.println("代理方法");
        subject.Request();
    }
}