interface Fruit{
    public void eat();
}
class Apple implements Fruit{
    public void eat(){
        System.out.println("吃苹果");
    }
}
class Orange implements Fruit{
    public void eat(){
        System.out.println("吃橘子");
    }
}
//下面定义一个工厂，取得子类的实例化对象；
class Factory{
    public static Fruit getInstance(String className){
        if("apple".equals(className)){
            return new Apple();
        }else if("orange".equals(className)){
            return new Orange();
        }else{
            return null;
        }
    }
}
public class Test{
    public static void main(String args[]){
        Fruit f = Factory.getInstance("apple");
        f.eat();
    }
}