方法重写的演示

package oo.day05;
//方法重写的演示
public class OverrideDemo {
public static void main(String[] args) {
}
}

class Aoo{
void show(){}
double say(){return 0.0;}
Aoo get(){return null;}
Boo test(){return null;}
}
class Boo extends Aoo{
void show(){} //void时必须相同
double say(){return 2.2;} //基本数据类型时必须相同
Boo get(){return null;}
//Aoo test(){return null;} //编译错误，小于或等于
}