//Command声明执行操作的接口 abstract class Command { protected Receiver receiver; public Command(Receiver receiver) { this.receiver = receiver; } public abstract void execute(); } //creteCommand将一个接收者对象绑定于一个动作。调用接收者相应的操作，以实现Execute。 class CommandImpl extends Command { public CommandImpl(Receiver receiver) { super(receiver); } public void execute() { receiver. receive (); } } //Invoker要求该命令执行这个请求。 class Invoker { private Command command; public void setCommand(Command command) { this.command = command; } public void execute() { command.execute(); } } //Receiver知道如何实现与执行一个请求相关的操作。任何类都可能作为一个接收者。 class Receiver { public void receive() { System.out.println("This is Receive class!"); } } public class DS14_Command{ public static void main(String[] args) { Receiver rec = new Receiver(); Command cmd = new CommandImpl(rec); Invoker i = new Invoker(); i.setCommand(cmd); i.execute(); } }