java 封装工具类

abstract class Animal{public abstract void eat();public abstract void jiao();}//封装行为工具类——动物具有的一些行为class DoAnimal{public void doSome(Animal a){a.eat();a.jiao();}}class Cat extends Animal{public void eat(){System.out.println("吃鱼");}public void jiao(){System.out.println("喵喵");}public void catchMouse(){System.out.println("捉老鼠");//特有方法}}class Dog extends Animal{public void eat(){System.out.println("吃骨头");}public void jiao(){System.out.println("汪汪");}public void kanJia(){System.out.println("看家");//特有方法}}class DuoTaiDemo1{public static void main(String args[]){DoAnimal da=new DoAnimal();Cat c=new Cat();da.doSome(c);c.catchMouse();da.doSome(new Dog());}}