一个微波炉，叫你设计，需要用到什么设计模式？

最近学习+复习各种常用设计模式，看到一道题目http://www.iteye.com/topic/243309和http://topic.csdn.net/u/20091125/14/99c028d1-6cf0-4f82-b852-b94b84c4fb45.html，很有意思，不看不知道，面向对象真奇妙！

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其他人怎么说，不如自己练，于是用了单例模式，策略模式和命令模式写了一个初版的微波炉，考虑了微波炉操作的时候不能开门。策略模式用于烹饪鱼和鸡等一套【高级】微波炉功能，命令模式用于“煮”，“煎”，“高火”，“中火”，“低火”等【基础】功能。

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测试类CookFishTest：

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package com.hui.test;import java.util.ArrayList;import java.util.List;import com.hui.Machine;import com.hui.food.Fish;import com.hui.food.Food;import com.hui.strategy.CookFishStrategy;public class CookFishTest {public static void main(String[] args){CookFishTest cft = new CookFishTest();System.out.println("正常测试开始……");cft.regular();System.out.println("正常测试结束……");}private void regular(){Machine machine = Machine.getInstance();machine.openDoor();Fish fishA = new Fish();List<Food> fishList = new ArrayList<Food>();fishList.add(fishA);machine.putFood(fishList);machine.closeDoor();machine.setTime(10);machine.setCookStrategy(new CookFishStrategy(fishList));machine.operate();}} 

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各种命令，以”煮“为例：

package com.hui.command;public class BoilCommand implements Command {public void execute() {System.out.println("煮……");}}

各种策略，以烹饪鱼为例：

package com.hui.strategy;import java.util.ArrayList;import java.util.List;import com.hui.command.BoilCommand;import com.hui.command.Command;import com.hui.command.FryCommand;import com.hui.command.HighCommand;import com.hui.command.LowCommand;import com.hui.command.MiddleCommand;import com.hui.food.Fish;public class CookFishStrategy implements CookStrategy{//这里使用List<Food>会出错，原因大抵是"苹果可以是水果的子类//,但装苹果的袋子不是装水果的袋子的子类"private List<?> fishList = new ArrayList<Fish>();public CookFishStrategy(List<?> fishList){this.fishList = fishList;}public void cook(){Command boil = new BoilCommand();boil.execute();Command high = new HighCommand();high.execute();Command middle = new MiddleCommand();middle.execute();Command low = new LowCommand();low.execute();Command fry = new FryCommand();fry.execute();System.out.println("烹饪结束!可以取出食物!");}}

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策略类的接口：

package com.hui.strategy;public interface CookStrategy {public void cook();}

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微波炉主类：

package com.hui;import java.util.List;import com.hui.food.Food;import com.hui.strategy.CookStrategy;public class Machine {private CookStrategy cookStrategy;private List<Food> foodList;private static Machine instance;private int minutes;private byte[] lock = new byte[0]; private Machine(){System.out.println("这有一个微波炉A……");}public static synchronized Machine getInstance(){if(instance == null){instance = new Machine();}return instance;}public void openDoor(){synchronized(lock){System.out.println("开门……");}}public void closeDoor(){System.out.println("关门……");}public void setTime(int minutes){System.out.println("设置时间" + minutes + "分钟!");this.minutes = minutes;}public void putFood(List<Food> foodList){System.out.println("放食物……");this.foodList = foodList;}public void setCookStrategy(CookStrategy cookStrategy) {this.cookStrategy = cookStrategy;}public void operate(){synchronized(lock){cookStrategy.cook();}}}

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