1.Introduction

适配器模式是作为两个不兼容的接口之间的桥梁。这种类型的设计模式属于结构型模式，它结合了两个独立接口的功能。

2.Example

音频播放器设备只能播放mp3文件，通过使用一个更高级的音频播放器来播放vlc和mp4文件

3.Code

3.1 Source

// 需要被适配的接口
public interface AdvancedMediaPlayer {
    void playMp4(String fileName);
}

public class Mp4Player implements AdvancedMediaPlayer {
    @Override
    public void playMp4(String fileName) {
        System.out.println("Play Mp4, fileName " + fileName);
    }
}    

3.2 Target

// 最终需要的接口
public interface MediaPlayer {
    void play(String fileName);
}    

3.3 Adapter

public class MediaAdapter implements MediaPlayer {
    private AdvancedMediaPlayer advancedMediaPlayer;

    public MediaAdapter() {
        this.advancedMediaPlayer = new Mp4Player();
    }

    @Override
    public void play(String fileName) {
        advancedMediaPlayer.playMp4(fileName);
    }
}

3.Test

public class AdapterPatternDemo {
    public static void main(String[] args) {
        MediaPlayer mediaPlayer = new MediaAdapter();
        mediaPlayer.play("阿甘正传");
    }
}