【设计模式三】实战工厂汽车代工之工厂模式-简单模式

工厂模式

工厂模式（Factory Pattern）是 Java 中最常用的设计模式之一。这种类型的设计模式属于创建型模式，它提供了一种创建对象的最佳方式。

在工厂模式中，我们在创建对象时不会对客户端暴露创建逻辑，并且是通过使用一个共同的接口来指向新创建的对象。

简易UML图

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需求分析

每个品牌汽车都有一个生产的工厂，基本上都是几个大厂代工，然后换个牌子。

具体实现

package com.test.specific;/*** 生产汽车* @author 12134**/
public interface Car {/*** 制造*/void manufacture();/*** 运输*/void transport();}

package com.test.specific.impl;import com.test.specific.Car;/*** 宝马汽车* @author 12134**/
public class BaoMaCar implements Car{/*** 制造*/@Overridepublic void manufacture() {System.out.println("制造的汽车是宝马");}/*** 运输*/@Overridepublic void transport() {System.out.println("运输的汽车是宝马");}}

package com.test.specific.impl;import com.test.specific.Car;/*** 长安汽车* * @author 12134**/
public class ChangAnCar implements Car {/*** 制造*/@Overridepublic void manufacture() {System.out.println("制造的汽车是长安");}/*** 运输*/@Overridepublic void transport() {System.out.println("运输的汽车是长安");}}

package com.test.factory;import com.test.specific.Car;
import com.test.specific.impl.BaoMaCar;
import com.test.specific.impl.ChangAnCar;/*** 汽车代工工厂* @author 12134**/
public class CarFactory {/*** 代工* * @return 品牌*/public Car OEMCar(String carType) {if (carType == null) {return null;}Car car = null;if ("长安".equals(carType)) {car = new ChangAnCar();} else if ("宝马".equals(carType)) {car = new BaoMaCar();} else {throw new RuntimeException("该工厂没有代工" + carType + "品牌");}return car;}
}

package com.test;import com.test.factory.CarFactory;
import com.test.specific.Car;public class Main {public static void main(String[] args) {// 汽车代工工厂CarFactory carFactory = new CarFactory();// 代工品牌Car oemCar = carFactory.OEMCar("长安");// 汽车制造商oemCar.manufacture();// 汽车运输商oemCar.transport();}
}

结果

制造的汽车是长安
运输的汽车是长安