设计模式（八）--外观模式

外观模式：提供了一个统一的接口，用来访问子系统中的一大堆接口，外观定义了一个高层接口，让子系统更容易使用。

意图： 让接口更加简单。

public interface Light {
    void on();
    void off();
    void dim();
}

public interface Screen {
    void up();
    void down();
}

public interface DvdPlayer {
    void on();
    void off();
    void pause();
}

/**
 * 外观模式类
 * Created by Administrator on 2018/1/9.
 */
public class HomeTheaterFacade {
    private Screen screen;
    private DvdPlayer dvdPlayer;
    private Light light;

    public HomeTheaterFacade(Screen screen, DvdPlayer dvdPlayer, Light light) {
        this.screen = screen;
        this.dvdPlayer = dvdPlayer;
        this.light = light;
    }

    /**
     * 外观模式,
     * 将众多复杂的子模块封装起来，提供一个统一的调用
     * **/
    public void watchMovie(){
        screen.down();
        dvdPlayer.on();
        light.dim();
    }

    public void endMovie(){
        screen.up();
        dvdPlayer.off();
        light.on();
    }

}

public class TestFacade {
    public static void main(String[] args) {
        // screen ,light 通过各子类实现传入构造方法
        HomeTheaterFacade homeTheaterFacade = new HomeTheaterFacade(screen,dvdplayer,light);
        homeTheaterFacade.watchMovie();
        homeTheaterFacade.endMovie();
    }
}