工厂方法模式

Posted 2020-10-01 千彧

在简单工厂模式的基础上对工厂进行抽象化，不同的产品对应不同的具体工厂。

克服了简单工厂模式违背开闭原则。但在添加新产品时需要增加产品以及对应的工厂·增加负复杂度，给系统带来额外开销.

抽象产品类

1 public interface Freshwaterfish {
2 void grow();//鱼在生长
3 void harvest();//收获鱼
4 }

具体产品类

 1 public class Grasscrap implements Freshwaterfish {
 2 
 3     @Override
 4     public void grow() {
 5      System.out.println("草鱼在生长！");
 6     }
 7 
 8     @Override
 9     public void harvest() {
10     System.out.println("收获草鱼！");    
11     }
12 
13 }

 

 1 public class Carp implements Freshwaterfish {
 2 
 3     @Override
 4     public void grow() {
 5 System.out.println("鲤鱼在生长！");
 6     }
 7 
 8     @Override
 9     public void harvest() {
10     System.out.println("收获鲤鱼！");
11     }
12 
13 }

 抽象工厂类

1 public interface Fishfactory { 2 public Freshwaterfish producefish(); 3 } 

 具体工厂类

1 public class GrasscrapFactory implements Fishfactory {
2 
3     @Override
4     public  Freshwaterfish producefish() {
5         return new Grasscrap();
6     }
7 
8 }

 

1 public class CarpFactory implements Fishfactory {
2 
3     @Override
4     public  Freshwaterfish producefish() {
5         return new Carp();
6     }
7 
8 }

客户测试类

1 public class SimpleFactory {
2 
3 public static void main(String[] args) {
4 Fishfactory grassfactory =  new GrasscrapFactory();
5  Freshwaterfish grasscrap =  grassfactory.producefish();
6  grasscrap.grow();
7  grasscrap.harvest();
8 }
9 }