设计模式（六）--命令模式

命令模式：将请求封装成对象，以便使用不同的请求、队列或者日志来参数化其他对象。命令模式也支持可撤销的操作。

public interface Command {
    /**
     * 执行动作
     * */
    void execute();
    /**
     * 撤销功能
     * */
    void undo();
}

public class Light {
    public void on(){
        System.out.println("light is on");
    }
    public void off(){
        System.out.println("light is off");
    }

}

public class LightOnCommand  implements  Command{

    private final Light light;

    public LightOnCommand(Light light) {
        this.light = light;
    }

    @Override
    public void execute() {
        light.on();
    }

    @Override
    public void undo() {
        System.out.println("undo");
    }
}

package com.em.command;

/**
 * 遥控器
 * Created by Administrator on 2018/1/6.
 */
public class RemoteControl {
    private Command command;

    public Command getCommand() {
        return command;
    }

    public void setCommand(Command command) {
        this.command = command;
    }

    /**
     * 执行操作
     * */
    public void buttonWasPress(){
        command.execute();
    }

    public static void main(String[] args) {
        Light light = new Light();
        LightOnCommand lightOnCommand = new LightOnCommand(light);
        RemoteControl remoteControl = new RemoteControl();
        remoteControl.setCommand(lightOnCommand); //设置命令
        remoteControl.buttonWasPress();
    }
}