设计模式 命令模式

概念

命令符合下面这个场景

结构

案例

定义一个执行接口:

public interface Command {
    void execute();
}

定义订单类

@Data
public class Order {
    //餐桌号码
    private int diningTable;

    //用来存储餐名以及份数
    private Map<String,Integer> foodDic = new HashMap<>();
}

定义接受者 大厨类

public class SeniorChef {

    public void makeFood(int num,String foodName){
        System.out.println(num + "份" + foodName);
    }
}

定义命令对象 集成订单和大厨

public class OrderCommand implements Command{

    private SeniorChef receiver;
    private Order order;

    public OrderCommand(SeniorChef receiver, Order order) {
        this.receiver = receiver;
        this.order = order;
    }

    @Override
    public void execute() {
        System.out.println(order.getDiningTable() + "桌的订单:");
        Set<String> keys = order.getFoodDic().keySet();
        for(String key : keys){
            receiver.makeFood(order.getFoodDic().get(key),key);
        }
        System.out.println(order.getDiningTable() + "桌的饭做好了");
    }
}

定义发布命令者 服务器

public class Waiter {
    private ArrayList<Command> commands;

    public Waiter(ArrayList<Command> commands) {
        this.commands = commands;
    }

    public void addCommand(Command command){
        commands.add(command);
    }

    //发出命令 喊订单来了 厨师开始执行
    public void orderUp(){
        System.out.println("服务员:订单来了");
        for (int i = 0; i < commands.size(); i++) {
            Command cmd = commands.get(i);
            if(cmd != null){
                cmd.execute();
            }
        }
    }
}

测试使用:

public class Client {
    public static void main(String[] args) {
        //创建两个order
        Order order1 = new Order();
        order1.setDiningTable(1);
        order1.getFoodDic().put("西红柿炒鸡蛋",1);
        order1.getFoodDic().put("小杯可乐",2);

        Order order2 = new Order();
        order2.setDiningTable(2);
        order2.getFoodDic().put("漏丸",1);
        order2.getFoodDic().put("雪碧",1);

        //创建接收者
        SeniorChef receiver = new SeniorChef();
        //将订单和接收者(厨师)封装成命令对象
    }
}