简单的工厂模试

//动物类接口      
interface Animal{      
    //发出声音      
    public class sayHello(){};      
}      
     
//生产动物的工厂类      
class AnimalFactory{      
    public static Animal createDog(){      
        return (Animal)new Dog();      
    }      
}      
     
//狗实现动物接口      
class Dog implements Animal{      
    //狗会汪汪叫      
    public class sayHello(){      
        System.out.println("汪汪");      
    }      
}      
//外国狗实现动物接口      
class EnglishDog implements Animal{      
    //外国狗会Wolf!Wolf!叫      
    public class sayHello(){      
        System.out.println("Wolf!Wolf!");      
    }      
}      
  
//测试用   
class Test(){   
    public static void main(String [] args){      
        //从工厂类里面获取一只狗      
        Animal animal1 = AnimalFactory.createDog();      
       animal1.sayHello();      
    }   
}