设计模式--抽象工厂模式

抽象工厂模式

介绍

为创建一组相关或相互依赖的对象提供一个接口，而且无需指定他们的具体类。（创建型模式）

和工厂模式区别

工厂模式提供一个产品的结构，而抽象工厂模式提供多个产品的结构，可以组成一个产品族。

QQ换皮肤可以使用抽象工厂模式

优点：当一个产品族中的多个对象被设计成一起工作时，它能保证客户端始终只使用同一个产品族中的对象。
缺点：扩展非常麻烦，需要修改很多代码。

DEMO

可以在前一个例子上给图形增加颜色，就相当于一个产品族了：

先创建一个图形和颜色的接口类：

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */public interface Color {    void fill();}

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */public interface Shape {    void draw();}

然后分别实现各自两个类进行测试：

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */public class Black implements Color {    @Override    public void fill() {        System.out.println("Black : fill()");    }}

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */public class Red implements Color {    @Override    public void fill() {        System.out.println("Red : fill()");    }}

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */public class Circle implements Shape {    @Override    public void draw() {        System.out.println("Circle : draw()");    }}

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */public class Rectangle implements Shape {    @Override    public void draw() {        System.out.println("Rectangle : draw()");    }}

然后实现工厂抽象类：

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */public abstract class AbstractFactory {    abstract Color getColorFactory(String color);    abstract Shape getShapeFactory(String shape);}

然后扩展工厂抽象类：

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */public class ShapeFactory extends AbstractFactory {    @Override    Color getColorFactory(String color) {        return null;    }    @Override    Shape getShapeFactory(String shape) {        if(shape == null) {            return null;        }        if ("rectangle".equals(shape)){            return new Rectangle();        }else if ("circle".equals(shape)){            return new Circle();        }else {            return null;        }    }}

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */public class ColorFactory extends AbstractFactory {    @Override    Color getColorFactory(String color) {        if(color == null) {            return null;        }        if("red".equals(color)){            return new Red();        }else if("black".equals(color)){            return new Black();        }else {            return null;        }    }    @Override    Shape getShapeFactory(String shape) {        return null;    }}

然后写一个工厂创造器：

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */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;    }}

最后写一个测试类来试试输出：

package factory.pattern.abs;/** * Created by FK on 2017/6/18. */public class AbstractFactoryPattern {    public static void main(String[] args) {        AbstractFactory shapeFactory = FactoryProducer.getFactory("shape");        Shape shape1 = shapeFactory.getShapeFactory("circle");        shape1.draw();        Shape shape2 = shapeFactory.getShapeFactory("rectangle");        shape2.draw();        AbstractFactory colorFactory = FactoryProducer.getFactory("color");        Color color1 = colorFactory.getColorFactory("red");        color1.fill();        Color color2 = colorFactory.getColorFactory("black");        color2.fill();    }}

输出如果如下:

Circle : draw()Rectangle : draw()Red : fill()Black : fill()

博客来自
fk5431
http://fk5431.com/20170618/Design_pattern/abstract-factory-pattern/
希望去新博客踩踩!

代码都在github上，地址是fk5431
https://github.com/fk5431/designPatterns