介面卡模式

介面卡模式（Adapter Pattern）是作為兩個不相容的介面之間的橋樑。這種型別的設計模式屬於結構型模式，它結合了兩個獨立介面的功能。

這種模式涉及到一個單一的類，該類負責加入獨立的或不相容的介面功能。

例項：MP3播放器可以播放MP3格式的檔案，MP4播放器可以播放MP4格式的檔案，我們想實現MP4播放器既可以播放MP4也可以播放MP3格式檔案。通過adapter類，實現這一功能。

package com.wms.adapterPattern;

/**
 * @date:2018/11/14
 * @desc:
 */
public interface Players {

    void play(String type, String name);
}
 

package com.wms.adapterPattern;

/**
 * @date:2018/11/14
 * @desc:
 */
public class Mp3Player implements Players {


    public void play(String type, String name) {
        if (type.equals("mp3"))
            System.out.println("play mp3....");
        else System.out.println("not support" + name);
    }
}
 

package com.wms.adapterPattern;

/**
 * @date:2018/11/14
 * @desc: 介面卡
 */
public class Adapter extends Mp3Player {

    private Mp3Player mp3Player;

    public Adapter(Mp3Player mp3Player) {
        this.mp3Player = mp3Player;
    }

    public void play(String type, String name) {
        if (type.equals("mp3"))
            this.mp3Player.play(type, name);
    }


}
 

package com.wms.adapterPattern;

import com.sun.xml.internal.bind.v2.model.core.ID;

/**
 * @date:2018/11/14
 * @desc:
 */
public class Mp4Player implements Players {

    private Adapter adapter;

    public Mp4Player(Adapter adapter) {
        this.adapter = adapter;
    }

    public void play(String type, String name) {
        if (type.equals("mp4")) {
            System.out.println("play mp4....");
        } else if (type.equals("mp3")) {
            this.adapter.play(type,name);
        }
    }
}

package com.wms.adapterPattern;

/**
 * @date:2018/11/14
 * @desc: 需求：讓MP4可以播放MP3
 */
public class AdapterDemo {

    public static void main(String[] args) {
        Adapter adapter = new Adapter(new Mp3Player());

        Mp4Player mp4Player = new Mp4Player(adapter);

        mp4Player.play("mp3", "music");


    }
}

 實現MP4播放器可以播放MP3格式的檔案。