思考:工厂方法模式:http://www.cnblogs.com/maggiejyt/p/7561253.html
工厂方法模式UML:
问题:如果这家工厂不止要生产Ball(球),还要还有Sneakers(球鞋)等
则UML图为
当Product有多种类时则是抽象工厂模式
代码(Ball的代码见简单工厂模式:http://www.cnblogs.com/maggiejyt/p/7561253.html)
Sneakers(球鞋抽象类)
package com.maggie.FactoryMethod; public abstract class Sneakers { private String name; public Sneakers(String name) { super (); this .name = name; } public Sneakers() { super (); } public String getName() { return name; } public void setName(String name) { this .name = name; } public abstract void show(); }
FootSneakers(足球鞋)
package com.maggie.FactoryMethod; public class FootSneakers extends Sneakers { @Override public void show() { String show = "the sneakers is " + this .getName(); System.out.println(show); } public FootSneakers() { super (); } public FootSneakers(String name) { super (name); } }
BasketSneakers(篮球鞋)
package com.maggie.FactoryMethod; public class BasketSneakers extends Sneakers { @Override public void show() { String show = "the sneakers is "+ this .getName(); System.out.println(show); } public BasketSneakers() { super(); } public BasketSneakers(String name) { super(name); } }
IFactory(工厂接口)
package com.maggie.FactoryMethod; public interface IFactory { public abstract Ball createBall(); public abstract Sneakers createSneakers(); }
FootSneakers(足球工厂)
package com.maggie.FactoryMethod; public class FootSneakers extends Sneakers { @Override public void show() { String show = "the sneakers is " + this.getName(); System.out.println(show); } public FootSneakers() { super(); } public FootSneakers(String name) { super(name); } }
BasketFactory(篮球工厂)
package com.maggie.FactoryMethod; public class BasketFactory implements IFactory { @Override public Ball createBall() { // TODO Auto-generated method stub return new BasketBall("oranger"); } @Override public Sneakers createSneakers() { return new BasketSneakers("basketball sneakers"); } }
客户端调用
package com.maggie.FactoryMethod; public class Client { public static void main(String[] args) { IFactory iFactory = null; iFactory = new FootFactory(); Ball footBall = iFactory.createBall(); Sneakers footSneakers = iFactory.createSneakers(); footBall.play(); footSneakers.show(); iFactory = new BasketFactory(); Ball basketBall = iFactory.createBall(); Sneakers basketSneakers = iFactory.createSneakers(); basketBall.play(); basketSneakers.show(); } }
结果输出:
the ball's color is white+black,I am FootBall
the sneakers is football sneakers
the ball's color is oranger,I am BasketBall
the sneakers is basketball sneakers
思考:
每次增加一种产品类,就要改动各种Factory的代码。。。。。
采用的是用简单工厂来改进抽象工厂
代码实现
SportsEquipmentFactory(采用简单工厂模式来改进)
package com.maggie.FactoryMethod; public class SportsEquipmentFactory { private static final String STYLE = "basket"; // private static final String STYLE="foot";只需要更改这里的代码配置 public static Ball createBall() { Ball ball = null; switch (STYLE) { case "basket": ball = new BasketBall("oranger"); break; case "foot": ball = new FootBall("white+black"); break; } return ball; } public static Sneakers createSneakers() { Sneakers sneakers = null; switch (STYLE) { case "basket": sneakers = new BasketSneakers("basketball sneakers"); break; case "foot": sneakers = new FootSneakers("football sneakers"); break; } return sneakers; } }
客户端调用
package com.maggie.FactoryMethod; public class Client { public static void main(String[] args) { Ball ball = SportsEquipmentFactory.createBall(); ball.play(); Sneakers sneakers = SportsEquipmentFactory.createSneakers(); sneakers.show(); } }
输出
the ball's color is oranger,I am BasketBall the sneakers is basketball sneakers
思考:如果业务又做大,工厂又需要生产网球类的产品,则需要在SportsEquipmentFactory的switch中增加case,这又违反了开放-封闭原则
这时就要考虑反射。。。。