抽象工厂模式

抽象工厂模式

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代码实现

• 创建一个形状接口

public interface Shape {
   void draw();
}

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-创建实现接口的实体类

//长方形
public class Rectangle implements Shape {
 
   @Override
   public void draw() {
      System.out.println("Inside Rectangle::draw() method.");
   }
}

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//正方形
public class Square implements Shape {
 
   @Override
   public void draw() {
      System.out.println("Inside Square::draw() method.");
   }
}

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//圆形
public class Circle implements Shape {
 
   @Override
   public void draw() {
      System.out.println("Inside Circle::draw() method.");
   }
}

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• 创建一个颜色接口

public interface Color {
   void fill();
}

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• 创建接口的实现类

//红色
public class Red implements Color {
 
   @Override
   public void fill() {
      System.out.println("Inside Red::fill() method.");
   }
}

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//绿色
public class Green implements Color {
 
   @Override
   public void fill() {
      System.out.println("Inside Green::fill() method.");
   }
}

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• 为颜色和形状创建抽象类(接口)来获取工厂

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

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• 创建扩展了抽象工厂的工厂类，根据给定信息生产指定产品

public class ShapeFactory extends AbstractFactory {
    
   @Override
   public Shape getShape(String shapeType){
      if(shapeType == null){
         return null;
      }        
      if(shapeType.equalsIgnoreCase("CIRCLE")){
         return new Circle();
      } else if(shapeType.equalsIgnoreCase("RECTANGLE")){
         return new Rectangle();
      } else if(shapeType.equalsIgnoreCase("SQUARE")){
         return new Square();
      }
      return null;
   }
   
   @Override
   public Color getColor(String color) {
      return null;
   }
}

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public class ColorFactory extends AbstractFactory {
    
   @Override
   public Shape getShape(String shapeType){
      return null;
   }
   
   @Override
   public Color getColor(String color) {
      if(color == null){
         return null;
      }        
      if(color.equalsIgnoreCase("RED")){
         return new Red();
      } else if(color.equalsIgnoreCase("GREEN")){
         return new Green();
      } else if(color.equalsIgnoreCase("BLUE")){
         return new Blue();
      }
      return null;
   }
}

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创建一个工厂生成器

public class FactoryProducer {
   public static AbstractFactory getFactory(String choice){
      if(choice.equalsIgnoreCase("SHAPE")){
         return new ShapeFactory();
      } else if(choice.equalsIgnoreCase("COLOR")){
         return new ColorFactory();
      }
      return null;
   }
}

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• 测试

public class AbstractFactoryPatternDemo {
   public static void main(String[] args) {
 
      //获取形状工厂
      AbstractFactory shapeFactory = FactoryProducer.getFactory("SHAPE");
 
      //获取形状为 Circle 的对象
      Shape shape1 = shapeFactory.getShape("CIRCLE");
 
      //调用 Circle 的 draw 方法
      shape1.draw();
 
      //获取形状为 Rectangle 的对象
      Shape shape2 = shapeFactory.getShape("RECTANGLE");
 
      //调用 Rectangle 的 draw 方法
      shape2.draw();
      
      //获取形状为 Square 的对象
      Shape shape3 = shapeFactory.getShape("SQUARE");
 
      //调用 Square 的 draw 方法
      shape3.draw();
 
      //获取颜色工厂
      AbstractFactory colorFactory = FactoryProducer.getFactory("COLOR");
 
      //获取颜色为 Red 的对象
      Color color1 = colorFactory.getColor("RED");
 
      //调用 Red 的 fill 方法
      color1.fill();
 
      //获取颜色为 Green 的对象
      Color color2 = colorFactory.getColor("Green");
 
      //调用 Green 的 fill 方法
      color2.fill();
 
      //获取颜色为 Blue 的对象
      Color color3 = colorFactory.getColor("BLUE");
 
      //调用 Blue 的 fill 方法
      color3.fill();
   }
}

抽象工厂

public abstract class AbstractFactory{
    //不允许外部访问
    protected abstract Car getCar();
    
    public Car getCar(String name){
        if("BMW".equals(name)){
            return new BMWfactory().getCar();
        }else if("Benz".equals(name)){
            return new Benzfactory().getCar();
        }else if("Audi".equals(name)){
            return new Audifactory().getCar();
        }else{
            return null;
        }
    }
}


public class DefaultFactory extends AbstractFactory{
private AudiFactory defaultFactory = new AudiFactory();
    @Override
    protected abstract Car getCar(){
        return defaultFactory.getCar();
    }
}

public class AudiFactory extends AbstractFactory{
    public Car getCar(){
        return new Audi();
    }
}
public class BMWFactory extends AbstractFactory{
    public Car getCar(){
        return new BMW();
    }
}
public class BenzFactory extends AbstractFactory{
    public Car getCar(){
        return new Benz();
    }
}

• 测试

public static void main(String []args){
    DefaultFactory factory = new DefaultFactory();
    factory.get("Benz");
}