参考实例：http://www.cnblogs.com/java-my-life/archive/2012/03/28/2418836.html

抽象工厂模式的缺点

• 不太容易扩展新的产品

　　如果需要给整个产品族添加一个新的产品，那么就需要修改抽象工厂，这样就会导致修改所有的工厂实现类。

===================

工厂 其实就是抽象出事物的共性或者相似之处，定义共同的接口，实现交给具体的子类处理的过程。

理解 产品族和等级的概念：

   1.抽象工厂：定义工厂接口，包含生产原味和草莓味的酸奶的方法；

   2.定义工厂的实现类：蒙牛工厂和伊利工厂，并实现接口的方法；

   3.抽象工厂：定义口味接口，包含原味接口和草莓味接口，每个接口包含该口味酸奶的价格的方法；

   4.定义口味接口的实现类：每个工厂都能生产原味和草莓味酸奶，因此每个工厂分别包含原味接口的实现类和草莓味接口的实现类，实现类中给出该口味酸奶的价格。

   5.顾客类：顾客购买酸奶，只要说明要买酸奶的厂家，既得到该厂家下不同口味酸奶的价格信息；

   代码如下：

定义 草莓味接口：

package iv.factory.feidanyi.yuanshi.interfaces;

public interface CaoMeiWei {

	void getPrice();
}

定义草莓味的实现类：蒙牛草莓味

package iv.factory.feidanyi.yuanshi.classes;

import iv.factory.feidanyi.yuanshi.interfaces.CaoMeiWei;

public class MengNiuCmw implements CaoMeiWei {

	private int price =0;
	
	public MengNiuCmw(int price){
		this.price = price;
	}
	public void getPrice() {
		// TODO Auto-generated method stub
		System.out.println("蒙牛草莓味价格："+this.price);
	}

}

定义草莓味的实现类：伊利草莓味

package iv.factory.feidanyi.yuanshi.classes;

import iv.factory.feidanyi.yuanshi.interfaces.CaoMeiWei;

public class YiLiCmw implements CaoMeiWei {

	private int price =0;
	
	public YiLiCmw(int price){
		this.price = price;
	}
	public void getPrice() {
		// TODO Auto-generated method stub
		System.out.println("伊利草莓味价格："+this.price);
	}

}

定义原味接口：

package iv.factory.feidanyi.yuanshi.interfaces;

public interface YuanWei {
	
	void getPrice();
}

定义原味接口的实现类：蒙牛原味：

package iv.factory.feidanyi.yuanshi.classes;

import iv.factory.feidanyi.yuanshi.interfaces.YuanWei;

public class MengNiuYw implements YuanWei{
	private short price =0;
	private String brand ="";
	public MengNiuYw(int price){
		this.price = (short) price;
	}
	public void getPrice() {
		// TODO Auto-generated method stub
		System.out.println("原味价格："+this.price);
	}
	public void getBrand() {
		// TODO Auto-generated method stub
		System.out.println("品牌："+this.brand);
	}

}

定义原味接口的实现类：伊利原味：

package iv.factory.feidanyi.yuanshi.classes;

import iv.factory.feidanyi.yuanshi.interfaces.YuanWei;

public class YiLiYw implements YuanWei{
	
	private int price =0;
	private String brand = "";
	
	public YiLiYw(int price){
		this.price = price;
	}

	public void getPrice() {
		// TODO Auto-generated method stub
		System.out.println("原味价格："+this.price);
	}

}

定义厂家的接口：

package iv.factory.feidanyi.yuanshi.interfaces;

public interface AbstractFactory {

	YuanWei createYuanWei();
	CaoMeiWei createCaoMeiWei();
}

定义厂家的接口的实现类：蒙牛厂家：

package iv.factory.feidanyi.yuanshi.classes;

import iv.factory.feidanyi.yuanshi.interfaces.AbstractBrandFactory;
import iv.factory.feidanyi.yuanshi.interfaces.AbstractFactory;
import iv.factory.feidanyi.yuanshi.interfaces.CaoMeiWei;
import iv.factory.feidanyi.yuanshi.interfaces.YuanWei;

public class MengNiuFactory implements AbstractFactory,AbstractBrandFactory {

	public CaoMeiWei createCaoMeiWei() {
		// TODO Auto-generated method stub
		return new MengNiuCmw(14);
	}

	public YuanWei createYuanWei() {
		// TODO Auto-generated method stub
		return new MengNiuYw(15);
	}
	public String getBrand() {
		// TODO Auto-generated method stub
		return new MengNiu().getBrand();
	}
}

定义厂家的接口的实现类：伊利厂家：

package iv.factory.feidanyi.yuanshi.classes;

import iv.factory.feidanyi.yuanshi.interfaces.AbstractBrandFactory;
import iv.factory.feidanyi.yuanshi.interfaces.AbstractFactory;
import iv.factory.feidanyi.yuanshi.interfaces.CaoMeiWei;
import iv.factory.feidanyi.yuanshi.interfaces.YuanWei;

public class YiLiFactory implements AbstractFactory,AbstractBrandFactory {

	public CaoMeiWei createCaoMeiWei() {
		// TODO Auto-generated method stub
		return new YiLiCmw(11);
	}

	public YuanWei createYuanWei() {
		// TODO Auto-generated method stub
		return new YiLiYw(12);
	}

	public String getBrand() {
		// TODO Auto-generated method stub
		return new YiLi().getBrand();
	}
}

定义顾客类：

package iv.factory.feidanyi.yuanshi.classes;

import iv.factory.feidanyi.yuanshi.interfaces.AbstractFactory;
import iv.factory.feidanyi.yuanshi.interfaces.CaoMeiWei;
import iv.factory.feidanyi.yuanshi.interfaces.YuanWei;

public class Customer {
	private YuanWei yw =null;
	private CaoMeiWei cmw = null;
	
	public void buyMilk(AbstractFactory af){
		
		yw = af.createYuanWei();
		cmw = af.createCaoMeiWei();
		yw.getPrice();
		cmw.getPrice();
	}
	
}

定义main方法类：

package iv.factory.feidanyi.yuanshi.classes;

import iv.factory.feidanyi.yuanshi.interfaces.AbstractBrandFactory;
import iv.factory.feidanyi.yuanshi.interfaces.AbstractFactory;

public class client {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Customer cus = new Customer();
		AbstractBrandFactory af0 = new MengNiuFactory();
		AbstractFactory af = new MengNiuFactory();
		System.out.println(af0.getBrand());
		cus.buyMilk(af);
		
		AbstractBrandFactory af11 = new YiLiFactory();
		AbstractFactory af1 = new YiLiFactory();
		System.out.println(af11.getBrand());
		cus.buyMilk(af1);
	}

}

完毕。

动态装载类：

Class.forName(String类型的类的包路径).newInstance();

设计模式：工厂模式

原文：http://blog.csdn.net/lbake/article/details/46439163