抽象工厂模式（Abstract Factory）

提供一个创建一系列相关或相互依赖的对象的接口，而不需指定它们具体的类。

通常在run-time式创建一个ConcreateFactory类的单体实例。这个ConcreteFactory创建ConcreteProduct对象。为了创建不同的ConcreteProduct对象，clients需要使用不同的ConcreteFactory。

AbstractFactory（ContinentFactory）

定义一个接口，用来创建抽象products。

ConcreteFactory（AfrciaFactory,AmericaFactory）

实现创建具体的Products。

AbstractProduct（Herbivore，Carnivore）

声明一个接口表示一种product类型

Product（Wildebeest，Lion，Bison，Wolf）

定义被相关Concrete factory创建的product对象

实现AbstractProduct接口

Client（AnimalWorld）

使用AbstractFactory和AbstractProduct类

 

 

代码：

//AbstractFactory

public interface ContinentFactory{

            public Herbivore CreateHerbivore();

            public Carnivore CreateCarnivore();

}

 

 

//ConcreteFactory

public class AfricaFactory implements ContinentFactory{

            public Herbivore CreateHerbivore(){

                        return new Wildebeest();

            }

            public Carnivore CreateCarnivore(){

                        return new Lion();

            }

}

 

public class AmericaFactory implements ContinentFactory{

            public Herbivore CreateHerbivore(){

                        return new Bison();

            }

            public Carnivore CreateCarnivore(){

                        return new Wolf();

            }

}

 

//AbstractProduct

 

public interface Herbivore{

}

 

 

public interface Carnivore{

            public void Eat(Herbivore h);

}

 

 

//Product

public class Wildebeest implements Herbivore{

}

 

public class Lion implements Carnivore{

            public void Eat(Herbivore h){

                        System.out.println(“Lion eats “ +h.getName());

            }                     

}

 

public class Bison implements Herbivore{

}

 

public class Wolf implements Carnivore{

            public void Eat(Herbivore h){

                        System.out.println(“Wolf eats “ +h.getName());

            }

}

 

//Client

public class AnimalWorld{

            private Herbivore herbivore;

            private Carnivore carnivore;

            public AnimalWorld(ContinentFactory factory){

                        carnivore=factory. CreateCarnivore();

                        herbivore=factory. CreateHerbivore();

            }

            //Mehtods

            public void RunFoodChain(){

                        carnivore.Eat(herbivore);

            }

            public static void  main(String[] args){

                        AnimalWorld world=new AnimalWorld(new AfricaFactory());

                        world.RunFoodChain();

                       

                        world=new AnimalWorld(new AmericaFactory());

                        world.RunFoodChain();

}

 

Output

Lion eats Wildebeest Wolf eats Bison