设计模式（七）Adapter Pattern适配器模式

适用场景：旧系统的改造升级

实际场景：java.io.InputStreamReader(InputStream)等

1.一个被适配的类

package com.littlepage.AdapterPattern;
/*
 * 被适配的类
 */
public class Adaptee {
    public void request(){
        System.out.println("对应可实现功能");
    }
}

2.客户端

package com.littlepage.AdapterPattern;
/*
 * 客户端
 */
public class Client {
    public void test1(Target t){
        t.handleReq();
    }
    public static void main(String[] args) {
        Client c=new Client();
        Target t=new Adapter2(new Adaptee());
        c.test1(t);

    }
}

3.适配器写法1

package com.littlepage.AdapterPattern;
/*
 * 适配器本身
 */
public class Adapter extends Adaptee implements Target {

    @Override
    public void handleReq() {
        super.request();
    }

}

适配器写法2

package com.littlepage.AdapterPattern;

public class Adapter2 implements Target{
    private Adaptee adaptee;

    public Adapter2(Adaptee adaptee) {
        this.adaptee = adaptee;
    }

    @Override
    public void handleReq() {
        adaptee.request();
    }

}

UML图