[设计模式]之七:命令模式

//厨师接收消息 做菜
public class Receiver {
	public void execute() {
		System.out.println("Execute command");
	}
}
// 服务员管理收到的各类别的命令，通知厨师去做，所以需要维持一个厨师的引用
//这里做了简化，其实服务员还可以单独做一个类，创建一个list保存各式各样的command
abstract class Command {
	protected Receiver receiver;
	
	public Command(Receiver receiver) {
		this.receiver = receiver;
	}
	
	abstract public void execute();
}
public class ConcreteCommand extends Command {

	public ConcreteCommand(Receiver receiver) {
		super(receiver);
	}

	@Override
	public void execute() {
		receiver.execute();
	}

}
//客户去点菜，所以需要服务员的引用
public class Invoker {
	private Command cmd;
	
	public void setCommand(Command cmd) {
		this.cmd = cmd;
	}
	
	public void executeCommand() {
		cmd.execute();
	}
}
//客户代码
public class main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Receiver r = new Receiver();
		Command c = new ConcreteCommand(r);
		Invoker i = new Invoker();
		
		i.setCommand(c);
		i.executeCommand();
	}

}