命令模式第二篇

命令模式第一篇中把问题简化成一个遥控器，它只有一个按钮和对应的插槽，可以控制一个装置。

根据需求，现在有7个插槽，每个插槽都有一个开和关按钮，可以控制一个装置。只需将远程控制

对象中的单个命令组件换成命令组件数组即可。再加一个控制整个装置的撤销按钮。

实现代码如下：

public interface Command {
    public void execute();
    public void undo();
}

public class GargeDoorCloseCommand implements Command{
    GargeDoor gargeDoor;
    public GargeDoorCloseCommand(GargeDoor gargeDoor)
    {
    this.gargeDoor=gargeDoor;
    }
    @Override
    public void execute() {
    // TODO Auto-generated method stub
    gargeDoor.close();
    }
    @Override
    public void undo() {
    // TODO Auto-generated method stub
    gargeDoor.open();
    }

}

public class GargeDoorOpenCommand implements Command{
    GargeDoor gargeDoor;
    public GargeDoorOpenCommand(GargeDoor gargeDoor)
    {
    this.gargeDoor=gargeDoor;
    }
    @Override
    public void execute() {
    // TODO Auto-generated method stub
    gargeDoor.open();
    }
    @Override
    public void undo() {
    // TODO Auto-generated method stub
    gargeDoor.close();
    }

}

public class LightOffCommand implements Command{
    Light light;
    public LightOffCommand(Light light)
    {
    this.light=light;
    }
    @Override
    public void execute() {
    // TODO Auto-generated method stub
    light.off();
    }
    @Override
    public void undo() {
    // TODO Auto-generated method stub
    light.on();
    }

}

public class LightOnCommand implements Command{
    Light light;
    public LightOnCommand(Light light)
    {
    this.light=light;
    }
    @Override
    public void execute() {
    // TODO Auto-generated method stub
    light.on();
    }
    @Override
    public void undo() {
    // TODO Auto-generated method stub
    light.off();
    }

}

public class NoCommand implements Command{

    @Override
    public void execute() {
    // TODO Auto-generated method stub
    }

    @Override
    public void undo() {
    // TODO Auto-generated method stub

    }

}

public class StereoOffCommand implements Command{
    Stereo stereo;
    public StereoOffCommand(Stereo stereo)
    {
    this.stereo=stereo;
    }
    @Override
    public void execute() {
    // TODO Auto-generated method stub
    stereo.off();
    }
    @Override
    public void undo() {
    // TODO Auto-generated method stub
    stereo.on();
    }
}

public class StereoOnWithCDCommand implements Command{
    Stereo stereo;
    public StereoOnWithCDCommand(Stereo stereo)
    {
    this.stereo=stereo;
    }
    @Override
    public void execute() {
    // TODO Auto-generated method stub
    stereo.on();
    stereo.setCD();
    stereo.setVolume(11);
    }
    @Override
    public void undo() {
    // TODO Auto-generated method stub
    stereo.off();
    }

}

public class Light {
    String description;

    public Light(String description)
    {
    this.description=description;
    }
    public void on()
    {
    System.out.println(description+"light is on");
    }
    public void off()
    {
    System.out.println(description+"light is close");
    }
}

public class GargeDoor {
    String description;

    public GargeDoor(String description)
    {
    this.description=description;
    }
    public void open()
    {
    System.out.println(description+"door is open");
    }
    public void close()
    {
    System.out.println(description+"door is close");
    }
}

public class Stereo {
    int volume;
    String description;

    public Stereo(String description)
    {
    this.description=description;
    }

    public void on()
    {
    System.out.println(description+"stereo on");
    }
    public void setCD()
    {
    }

    public void setVolume(int volume)
    {
    this.volume=volume;
    }
    public void off()
    {
    System.out.println(description+"stereo off");
    }

}

public class SimpleRemoteControl {
    Command[] onCommands;
    Command[] offCommands;
    Command undoCommand;
    static final int number=7;

    public SimpleRemoteControl()
    {
    onCommands=new Command[7];
    offCommands=new Command[7];
    Command noCommand=new NoCommand();
    for(int i=0;i<number;i++)
    {
    onCommands[i]=noCommand;
    offCommands[i]=noCommand;
    }
    undoCommand=noCommand;
    }

    public void setCommand(int slot,Command onCommand,Command         offCommand)
    {
    onCommands[slot]=onCommand;
    offCommands[slot]=offCommand;
    }


    public void onButtonWasPressed(int slot)
    {
    onCommands[slot].execute();
    undoCommand=onCommands[slot];
    }

    public void offButtonWasPressed(int slot)
    {
    offCommands[slot].execute();
    undoCommand=offCommands[slot];
    }

    public void undoButtonWasPushed()
    {
    undoCommand.undo();
    }

    public String toString()
    {
    StringBuffer stringBuffer=new StringBuffer();
    stringBuffer.append("
---- Remote Control ----
");
    for(int i=0;i<onCommands.length;i++)
    {
    stringBuffer.append("[slot "+i+"]     "+onCommands[i].getClass().getName()+" "+offCommands[i].getClass().getName()+"
");
    }
    return stringBuffer.toString();
    }
}

public class RemoteControlTest {
    public static void main(String[] args)
    {
    SimpleRemoteControl remoteControl=new SimpleRemoteControl();

    Light livingRoomLight=new Light("Living Room");
    Light kitchenLight=new Light("KitChen");
    GargeDoor gargeDoor=new GargeDoor("");
    Stereo stereo=new Stereo("Living Room");

    LightOnCommand livingRoomLightOn=new         LightOnCommand(livingRoomLight);
    LightOffCommand livingRoomLightOff=new LightOffCommand(livingRoomLight);

    LightOnCommand kitchenLightOn=new LightOnCommand(kitchenLight);
    LightOffCommand kitchenLightOff=new LightOffCommand(kitchenLight);

    GargeDoorOpenCommand gargeDooOpenr=new     GargeDoorOpenCommand(gargeDoor);
    GargeDoorCloseCommand gargeDooClose=new GargeDoorCloseCommand(gargeDoor);

    StereoOnWithCDCommand stereoOnWithCD=new StereoOnWithCDCommand(stereo);
    StereoOffCommand stereoOff=new StereoOffCommand(stereo);

    remoteControl.setCommand(0, livingRoomLightOn, livingRoomLightOff);
    remoteControl.setCommand(1, kitchenLightOn, kitchenLightOff);
    remoteControl.setCommand(2, gargeDooOpenr, gargeDooClose);
    remoteControl.setCommand(3, stereoOnWithCD, stereoOff);

    System.out.println(remoteControl);

    remoteControl.onButtonWasPressed(0);
    remoteControl.offButtonWasPressed(0);
    remoteControl.onButtonWasPressed(1);
    remoteControl.undoButtonWasPushed();
    remoteControl.onButtonWasPressed(2);
    remoteControl.offButtonWasPressed(2);
    remoteControl.undoButtonWasPushed();

    }
}