Override

1、两个类具有继承关系
2、两个方法的名称相同、入参想同（包括个数、参数的类型）、返回值相同

public class OverrideTest {

    public static void main(String[] args) {
        Cat cat = new Cat();
        cat.eat();
    }
}

class Animal{
    public Animal() {
    }

    public void eat(){
        System.out.println("Animal like eat");
    }
}

class Cat extends Animal{
    public Cat() {
    }

    @Override
    public void eat() {
        System.out.println("cat like eat fish");
    }
}