抽象工厂模式——肯德基消费

一 模式定义

• 抽象工厂模式提供了一个接口，用于创建相关或者依赖对象的家族，而不需要指定具体实现类。
• 抽象工厂模式允许客户使用抽象接口来创建一组相关的产品，客户类和工厂类分开，客户需要任何产品的时候，只需要向工厂请求即可，客户无须修改就可以获得新产品。

二 模式举例
1 模式分析
我们借用爸爸和儿子到肯德基店消费这一场景来说明这一模式，进行抽象分析后的截图如下


2 抽象工厂模式的静态建模


 
3 代码示例
3.1 抽象食物的建立
 抽象食物——AbstractBaseFood

package com.demo.factory.model;/** *  * 食物基类 *  * @author maofw *  */public abstract class AbstractBaseFood{// 类别protected String kind;// 数量protected int num;// 价格protected float price;// 合计public float totalPrice(){return this.num * this.price;}}

 食物接口——IFood

package com.demo.factory.model;/** * 抽象食物接口 *  * @author maofw *  */public interface IFood{/** * 打印输出食物信息 */void printMesage();}

 3.2 建立不同食物的抽象基类
 汉堡基类——Hamburg

package com.demo.factory.model;/** * 汉堡基类 *  * @author maofw *  */public abstract class Hamburg extends AbstractBaseFood implements IFood{public void printMesage(){System.out.println("--" + this.kind + "风味汉堡，\t单价：" + this.price + "，\t数量：" + this.num + "，\t合计：" + this.totalPrice());}}

 鸡翅基类——ChickenWings

package com.demo.factory.model;/** * 鸡翅基类 *  * @author maofw *  */public abstract class ChickenWings extends AbstractBaseFood implements IFood{public void printMesage(){System.out.println("--" + this.kind + "风味鸡翅，\t单价：" + this.price + "，\t数量：" + this.num + "，\t合计：" + this.totalPrice());}}

 薯条基类——FrenchFries

package com.demo.factory.model;/** * 薯条基类 *  * @author maofw *  */public abstract class FrenchFries extends AbstractBaseFood implements IFood{public void printMesage(){System.out.println("--" + this.kind + "风味薯条，\t单价：" + this.price + "，\t数量：" + this.num + "，\t合计：" + this.totalPrice());}}

 饮料基类——Beverage

package com.demo.factory.model;/** * 饮料基类 *  * @author maofw *  */public abstract class Beverage extends AbstractBaseFood implements IFood{public void printMesage(){System.out.println("--" + this.kind + "饮料，\t单价：" + this.price + "，\t数量：" + this.num + "，\t合计：" + this.totalPrice());}}

 3.3 创建具体的食物
 麻辣鸡腿汉堡——ChinaHanburm

package com.demo.factory.model.kfc;import com.demo.factory.model.Hamburg;/** * 中国风味的麻辣鸡腿汉堡 *  * @author maofw *  */public class ChinaHanburm extends Hamburg{/** * 构造方法 *  * @param kind * @param price * @param num */public ChinaHanburm(int num){this.kind = "麻辣";this.price = 14.0f;this.num = num;}}

 奥尔良鸡翅——ChinaChickenWings

package com.demo.factory.model.kfc;import com.demo.factory.model.ChickenWings;/** * 鸡翅实现类 *  * @author maofw *  */public class ChinaChickenWings extends ChickenWings{public ChinaChickenWings(int num){this.kind = "奥尔良";this.price = 2.5f;this.num = num;}}

 薯条——ChinaFrenchFries

package com.demo.factory.model.kfc;import com.demo.factory.model.FrenchFries;/** * 薯条实现类 *  * @author maofw *  */public class ChinaFrenchFries extends FrenchFries{public ChinaFrenchFries(int num){this.kind = "普通";this.price = 8.0f;this.num = num;}}

 可乐——ChinaBeverage

package com.demo.factory.model.kfc;import com.demo.factory.model.Beverage;/** * 饮料实现类 *  * @author maofw *  */public class ChinaBeverage extends Beverage{public ChinaBeverage(int num){this.kind = "可乐";this.price = 7.0f;this.num = num;}}

 3.4 建立工厂
 创建抽象肯德基工厂——IKfcFactory 生产抽象食物

package com.demo.factory.itf;import com.demo.factory.model.Beverage;import com.demo.factory.model.ChickenWings;import com.demo.factory.model.FrenchFries;import com.demo.factory.model.Hamburg;/** * 肯德基抽象工厂基类 *  * @author maofw *  */public interface IKfcFactory{// 生产汉堡public Hamburg createHamburg(int num);// 生产薯条public FrenchFries createFrenchFries(int num);// 生产鸡翅public ChickenWings createChickenWings(int num);// 生产饮料public Beverage createBeverage(int num);}

 创建具体肯德基工厂——ChinaKfcFactory 生产具体食物

package com.demo.factory.itf;import com.demo.factory.model.Beverage;import com.demo.factory.model.ChickenWings;import com.demo.factory.model.FrenchFries;import com.demo.factory.model.Hamburg;import com.demo.factory.model.kfc.ChinaBeverage;import com.demo.factory.model.kfc.ChinaChickenWings;import com.demo.factory.model.kfc.ChinaFrenchFries;import com.demo.factory.model.kfc.ChinaHanburm;public class ChinaKfcFactory implements IKfcFactory{// 生产可乐public Beverage createBeverage(int num){return new ChinaBeverage(num);}// 生产奥尔良烤鸡翅public ChickenWings createChickenWings(int num){return new ChinaChickenWings(num);}// 生产薯条public FrenchFries createFrenchFries(int num){return new ChinaFrenchFries(num);}// 生产麻辣风味鸡腿汉堡public Hamburg createHamburg(int num){return new ChinaHanburm(num);}}

 3.5 创建客户类——Customer

package com.demo.factory.custom;import com.demo.factory.itf.IKfcFactory;import com.demo.factory.model.Beverage;import com.demo.factory.model.ChickenWings;import com.demo.factory.model.FrenchFries;import com.demo.factory.model.Hamburg;/** * 客户类 *  * @author maofw *  */public class Customer{// 抽象工厂private IKfcFactory kfcFactory;// 构造方法将抽象工厂作为参数传入public Customer(IKfcFactory kfcFactory){this.kfcFactory = kfcFactory;}/** * 订购食物 */// 订购麻辣鸡腿汉堡public float orderHamburg(int num){// 获得麻辣鸡腿汉堡Hamburg hamburg = kfcFactory.createHamburg(num);// 输出订购信息hamburg.printMesage();// 返回总价return hamburg.totalPrice();}// 订购奥尔良烤鸡翅public float orderChickenWings(int num){// 获得奥尔良烤鸡翅ChickenWings chickenWings = kfcFactory.createChickenWings(num);// 输出订购信息chickenWings.printMesage();// 返回总价return chickenWings.totalPrice();}// 订购薯条public float orderFrenchFries(int num){// 获得薯条FrenchFries frenchFries = kfcFactory.createFrenchFries(num);// 输出订购信息frenchFries.printMesage();// 返回总价return frenchFries.totalPrice();}// 订购可乐public float orderBeverage(int num){// 获得可乐Beverage beverage = kfcFactory.createBeverage(num);// 输出订购信息beverage.printMesage();// 返回总价return beverage.totalPrice();}}

 3.6 故事情节展现

package com.demo.factory;import java.lang.management.ManagementFactory;import java.net.HttpURLConnection;import java.net.URL;import java.net.URLConnection;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.SQLException;import java.text.NumberFormat;import java.util.Arrays;import java.util.Calendar;import java.util.ResourceBundle;import com.demo.factory.custom.Customer;import com.demo.factory.itf.ChinaKfcFactory;import com.demo.factory.itf.IKfcFactory;public class MainApp{/** * 主应用程序方法 *  * @param args */public static void main(String[] args){/** * 定义一个肯德基（IKfcFactory类型） */IKfcFactory kfcFactory = new ChinaKfcFactory();/** * 爸爸和儿子走进肯德基，准备点餐 */Customer customer = new Customer(kfcFactory);/** * 开始点餐 */// 一个麻辣鸡腿汉堡float hamhurgMoney = customer.orderHamburg(1);// 四个奥尔良烤鸡翅float chickenWingsMoney = customer.orderChickenWings(4);// 一包薯条float frenchFriesMoney = customer.orderFrenchFries(1);// 两杯可乐float beverageMoney = customer.orderBeverage(2);System.out.println("总计：" + (hamhurgMoney + chickenWingsMoney + frenchFriesMoney + beverageMoney));}}

 运行结果：

--麻辣风味汉堡， 单价：14.0， 数量：1， 合计：14.0
--奥尔良风味鸡翅， 单价：2.5， 数量：4， 合计：10.0
--普通风味薯条， 单价：8.0， 数量：1， 合计：8.0
--可乐饮料， 单价：7.0， 数量：2， 合计：14.0
总计：46.0

 

三 该模式的设计原则
1 多用对象组合，少用继承
2 针对抽象编程，不针对实现编程
3 产品对象通过工厂暴露的方法创建

 

四 使用场合
1 创建产品家族，相关产品集合在一起使用的时候；
2 想要提供一个产品类库，并只想显示其接口而不是实现时；
3 通过组合的方式使用工厂时。