抽象工厂模式

抽象工厂模式也是一种工厂模式，只是它生产的对象是工厂。

代码演示

第1步：创建Shape的接口

Shape.java

1 public interface Shape {
2    void draw();
3 }

第2步：创建实现相同接口的具体类

Rectangle.java

1 public class Rectangle implements Shape {
2 
3    @Override
4    public void draw() {
5       System.out.println("Inside Rectangle::draw() method.");
6    }
7 }

Square.java

1 public class Square implements Shape {
2 
3    @Override
4    public void draw() {
5       System.out.println("Inside Square::draw() method.");
6    }
7 }

Circle.java

1 public class Circle implements Shape {
2 
3    @Override
4    public void draw() {
5       System.out.println("Inside Circle::draw() method.");
6    }
7 }

第3步：创建一个Colors接口

Color.java

1 public interface Color {
2    void fill();
3 }

第4步：创建实现相同接口的具体类

Red.java

1 public class Red implements Color {
2 
3    @Override
4    public void fill() {
5       System.out.println("Inside Red::fill() method.");
6    }
7 }

Green.java

1 public class Green implements Color {
2 
3    @Override
4    public void fill() {
5       System.out.println("Inside Green::fill() method.");
6    }
7 }

Blue.java

1 public class Blue implements Color {
2 
3    @Override
4    public void fill() {
5       System.out.println("Inside Blue::fill() method.");
6    }
7 }

第5步：创建实现相同接口的具体类

AbstractFactory.java

1 public abstract class AbstractFactory {
2    abstract Color getColor(String color);
3    abstract Shape getShape(String shape) ;
4 }

第6步：创建实现相同接口的具体类

创建工厂类，根据给定信息扩展AbstractFactory以生成具体类的对象

ShapeFactory.java

 1 public class ShapeFactory extends AbstractFactory {
 2 
 3    @Override
 4    public Shape getShape(String shapeType){
 5 
 6       if(shapeType == null){
 7          return null;
 8       }
 9 
10       if(shapeType.equalsIgnoreCase("CIRCLE")){
11          return new Circle();
12 
13       }else if(shapeType.equalsIgnoreCase("RECTANGLE")){
14          return new Rectangle();
15 
16       }else if(shapeType.equalsIgnoreCase("SQUARE")){
17          return new Square();
18       }
19 
20       return null;
21    }
22 
23    @Override
24    Color getColor(String color) {
25       return null;
26    }
27 }

ColorFactory.java

 1 public class ColorFactory extends AbstractFactory {
 2 
 3    @Override
 4    public Shape getShape(String shapeType){
 5       return null;
 6    }
 7 
 8    @Override
 9    Color getColor(String color) {
10 
11       if(color == null){
12          return null;
13       }        
14 
15       if(color.equalsIgnoreCase("RED")){
16          return new Red();
17 
18       }else if(color.equalsIgnoreCase("GREEN")){
19          return new Green();
20 
21       }else if(color.equalsIgnoreCase("BLUE")){
22          return new Blue();
23       }
24 
25       return null;
26    }
27 }

第7步：创建工厂生成器/生产器类，通过传递如Shape或Color等信息来获取工厂

FactoryProducer.java

 1 public class FactoryProducer {
 2    public static AbstractFactory getFactory(String choice){
 3 
 4       if(choice.equalsIgnoreCase("SHAPE")){
 5          return new ShapeFactory();
 6 
 7       }else if(choice.equalsIgnoreCase("COLOR")){
 8          return new ColorFactory();
 9       }
10 
11       return null;
12    }
13 }

第8步：使用FactoryProducer来获取AbstractFactory，以便通过传递类型等信息来获取具体类的工厂

AbstractFactoryPatternDemo.java

 1 public class AbstractFactoryPatternDemo {
 2    public static void main(String[] args) {
 3 
 4       //get shape factory
 5       AbstractFactory shapeFactory = FactoryProducer.getFactory("SHAPE");
 6 
 7       //get an object of Shape Circle
 8       Shape shape1 = shapeFactory.getShape("CIRCLE");
 9 
10       //call draw method of Shape Circle
11       shape1.draw();
12 
13       //get an object of Shape Rectangle
14       Shape shape2 = shapeFactory.getShape("RECTANGLE");
15 
16       //call draw method of Shape Rectangle
17       shape2.draw();
18 
19       //get an object of Shape Square 
20       Shape shape3 = shapeFactory.getShape("SQUARE");
21 
22       //call draw method of Shape Square
23       shape3.draw();
24 
25       //get color factory
26       AbstractFactory colorFactory = FactoryProducer.getFactory("COLOR");
27 
28       //get an object of Color Red
29       Color color1 = colorFactory.getColor("RED");
30 
31       //call fill method of Red
32       color1.fill();
33 
34       //get an object of Color Green
35       Color color2 = colorFactory.getColor("Green");
36 
37       //call fill method of Green
38       color2.fill();
39 
40       //get an object of Color Blue
41       Color color3 = colorFactory.getColor("BLUE");
42 
43       //call fill method of Color Blue
44       color3.fill();
45    }
46 }

第9步：验证输出，结果如下

1 Inside Circle::draw() method.
2 Inside Rectangle::draw() method.
3 Inside Square::draw() method.
4 Inside Red::fill() method.
5 Inside Green::fill() method.
6 Inside Blue::fill() method.

 

posted @ 2017-12-29 09:07  大明湖畔的守望者  阅读(166)  评论(0)  编辑  收藏  举报