向上/下转型

package com.itheima_04;

public class Animal {
    public void eat() {
        System.out.println("动物吃东西！");
    }
}

package com.itheima_04;

public class AnimalDemo {
    public static void main(String[] args) {
        //向上转型（父类引用指向子类对象）
        Animal a = new Cat();
        a.eat();

        //向下转型(父类引用转为子类对象）
        Cat c = (Cat) a;
        c.eat();
        c.palyGame();
    }
}

package com.itheima_04;

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

    public void palyGame() {
        System.out.println("著迷仓");
    }
}

输出：

吃鱼
吃鱼
著迷仓

Process finished with exit code 0