行为型模式-命令模式

package per.mjn.pattern.command;

import java.util.HashMap;
import java.util.Map;

// 订单类
public class Order {

    // 餐桌号码
    private int diningTable;

    // 点的餐品和份数
    private Map<String, Integer> foodDir = new HashMap<>();

    public int getDiningTable() {
        return diningTable;
    }

    public void setDiningTable(int diningTable) {
        this.diningTable = diningTable;
    }

    public Map<String, Integer> getFoodDir() {
        return foodDir;
    }

    public void setFood(String name, int num) {
        foodDir.put(name, num);
    }
}

package per.mjn.pattern.command;

// 厨师类
public class SeniorChef {

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

package per.mjn.pattern.command;

// 抽象命令类
public interface Command {

    void execute();
}

package per.mjn.pattern.command;

import java.util.Map;
import java.util.Set;

// 具体的命令类
public class OrderCommand implements Command {

    // 持有接受者对象
    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:");
        Map<String, Integer> foodDir = order.getFoodDir();

        // 遍历map集合
        Set<String> keys = foodDir.keySet();
        for (String foodName : keys) {
            receiver.makeFood(foodName, foodDir.get(foodName));
        }

        System.out.println(order.getDiningTable() + "桌的饭准备完毕!!!");
    }
}

package per.mjn.pattern.command;

import java.util.ArrayList;
import java.util.List;

// 服务员类，属于调用者角色
public class Waiter {

    // 持有多个命令对象
    private List<Command> commands = new ArrayList<>();

    public void setCommand(Command cmd) {
        // 将cmd对象存储到list集合中
        commands.add(cmd);
    }

    // 发起命令功能  喊 订单来了
    public void orderUp() {
        System.out.println("服务员说：大厨，新订单来了.");
        // 遍历list集合
        for (Command command : commands) {
            if (command != null) {
                command.execute();
            }
        }
    }
}

package per.mjn.pattern.command;

public class Client {
    public static void main(String[] args) {

        // 创建第一个订单对象
        Order order1 = new Order();
        order1.setDiningTable(1);
        order1.setFood("鸡翅", 2);
        order1.setFood("小杯可乐", 2);

        // 创建第二个订单对象
        Order order2 = new Order();
        order2.setDiningTable(2);
        order2.setFood("鸡排", 2);
        order2.setFood("小杯雪碧", 2);

        // 创建接受者对象（厨师对象）
        SeniorChef receiver = new SeniorChef();

        // 创建命令对象
        OrderCommand cmd1 = new OrderCommand(receiver, order1);
        OrderCommand cmd2 = new OrderCommand(receiver, order2);

        // 创建调用者（服务员对象）
        Waiter waiter = new Waiter();
        waiter.setCommand(cmd1);
        waiter.setCommand(cmd2);

        // 让服务员发起命令
        waiter.orderUp();
    }
}