对象向上转型

package cn.ly.Day.seven.twentytwo3;

public abstract class Animal {
    public abstract void eat();

}

package cn.ly.Day.seven.twentytwo3;

public class Cat extends  Animal {
    @Override
    public void eat() {
        System.out.println("猫爱吃鱼");
    }
}

package cn.ly.Day.seven.twentytwo3;

public class Dem03Main {
    public static void main(String[] args) {
        //对象的向上转型，就是，父类引用指向之类对象
        Animal animal=new Cat();
        animal.eat();
    }
}