首页 > 代码库 > 中介者模式

中介者模式

在生活中,当电脑缺少了一块主板,那会怎么样?如果有人这样问我的话,我就会马上跳出来说“这电脑肯定报废了”,当然这不是重点。假如少了主板电脑还可以用的话,想想,里面的CPU、显卡、声卡、光驱、硬盘等等,不是就要我们自己用线把它们连起来。想想就觉得头疼,那么现在你觉得主板在电脑里扮演着什么角色呢?

在软件的开发过程中,势必会碰到这样一种情况,多个类或多个子系统相互交互,而且交互很繁琐,导致每个类都必须知道他需要交互的类,这样它们的耦合会显得异常厉害。牵一发而动全身又不木有啊!(严重违反低耦合)

好了,既然问题提出来了,那有请我们这期的主角——中介者模式出场吧!

 

具体过程如下:

1.首先光驱读取光盘上的数据,然后告诉主板,它的状态已经改变了。

2.主板得到光驱的数据,将数据交给CPU进行分析处理。

3.CPU处理完,将数据分成了视频数据和音频数据,通知主板,已将处理好了。

4.主板得到数据,将数据交给显卡和声卡进行输出。

 

先用几句话说下这些代码,colleague是一个抽象类,是光驱、cpu等的父类,有对中介者mediator的引用,

然后mediator是一个接口,ConcreteMediator实现了它的change方法,有对光驱、cpu等的引用,每当光驱、cpu等自己工作完的时候就去调用中介者的change方法,

然后中介者的change就去做一些调兵遣将的工作比如派显卡和声卡工作,用户就能看到东西了,而这个过程,光驱、cpu等的操作都是隔离开的,没有在内部相互引用,

而都是放在中介者里面引用的!实现了模块间的低耦合!

 

 

Mediator

package designMode.mediator2;public interface Mediator {    void change(Colleague colleague);}

 

ConcreteMediator

package designMode.mediator2;public class ConcreteMediator implements Mediator {    private CDDriver cdDriver;    private CPU cpu;    private VideoCard video;    private SoundCard sound;    public void setCDDriver(CDDriver cdDriver) {        this.cdDriver = cdDriver;    }    public void setCPU(CPU cpu) {        this.cpu = cpu;    }    public void setVideoCard(VideoCard video) {        this.video = video;    }    public void setSoundCard(SoundCard sound) {        this.sound = sound;    }    public void change(Colleague colleague) {        if (colleague == cdDriver) {            openCDAndReadData((CDDriver) colleague);        } else if (colleague == cpu) {            openCPU((CPU) colleague);        }    }    private void openCDAndReadData(CDDriver cs) {        // 获取光驱读取的数据        String data =http://www.mamicode.com/ cdDriver.getData();        // 把这些数据传递给CPU进行处理        this.cpu.executeData(data);    }    private void openCPU(CPU cpu) {        // 获取数据        String videoData =http://www.mamicode.com/ cpu.getVideioData();        String soundData = cpu.getSoundData();        // 显示数据        this.video.showData(videoData);        this.sound.showData(soundData);    }}

 

Colleague

package designMode.mediator2;public abstract class Colleague {    private Mediator mediator;        public Colleague(Mediator mediator){        this.mediator = mediator;    }    public Mediator getMediator() {        return mediator;    }}

 

CPU

package designMode.mediator2;public class CPU extends Colleague {    public CPU(Mediator mediator) {        super(mediator);    }    private String videioData = http://www.mamicode.com/null;    private String soundData = http://www.mamicode.com/null;    public String getVideioData() {        return this.videioData;    }    public String getSoundData() {        return this.soundData;    }    public void executeData(String data) {        String[] ss = data.split(",");        this.videioData = http://www.mamicode.com/ss[0];        this.soundData = http://www.mamicode.com/ss[1];        // 通知主板,CPU工作已完成        this.getMediator().change(this);    }}

 

CDDriver

package designMode.mediator2;public class CDDriver extends Colleague {    public CDDriver(Mediator mediator) {        super(mediator);    }    private String data = http://www.mamicode.com/null;    public String getData()    {        return this.data;    }    public void readCD()    {        //逗号前是视频数据,逗号后是声音数据        this.data = "http://www.mamicode.com/这是视频数据,这是声音数据";        //通知主板,自己的状态反生了改变        this.getMediator().change(this);    }}

 

VideoCard

package designMode.mediator2;public class VideoCard extends Colleague {    public VideoCard(Mediator mediator) {        super(mediator);        // TODO Auto-generated constructor stub    }        public void showData(String data) {        System.out.println("您正在看:" + data);    }}

 

SoundCard

package designMode.mediator2;public class SoundCard extends Colleague {    public SoundCard(Mediator mediator) {        super(mediator);        // TODO Auto-generated constructor stub    }        public void showData(String data) {        System.out.println("您正在听:" + data);    }}

 

ConcreteMediator

package designMode.mediator2;public class ConcreteMediator implements Mediator {    private CDDriver cdDriver;    private CPU cpu;    private VideoCard video;    private SoundCard sound;    public void setCDDriver(CDDriver cdDriver) {        this.cdDriver = cdDriver;    }    public void setCPU(CPU cpu) {        this.cpu = cpu;    }    public void setVideoCard(VideoCard video) {        this.video = video;    }    public void setSoundCard(SoundCard sound) {        this.sound = sound;    }    public void change(Colleague colleague) {        if (colleague == cdDriver) {            openCDAndReadData((CDDriver) colleague);        } else if (colleague == cpu) {            openCPU((CPU) colleague);        }    }    private void openCDAndReadData(CDDriver cs) {        // 获取光驱读取的数据        String data =http://www.mamicode.com/ cdDriver.getData();        // 把这些数据传递给CPU进行处理        this.cpu.executeData(data);    }    private void openCPU(CPU cpu) {        // 获取数据        String videoData =http://www.mamicode.com/ cpu.getVideioData();        String soundData = cpu.getSoundData();        // cpu通知声卡显卡工作,用户就可以看到影像了        this.video.showData(videoData);        this.sound.showData(soundData);    }}

 

 

参考自:http://www.cnblogs.com/zxj159/p/3466115.html

中介者模式