java中抽象类和抽象方法到底什么关系？请举例说明！

来源：互联网发布：淘宝网访问验证编辑：程序博客网时间：2024/04/30 20:10

抽象类和抽象方法什么关系？抽象类中可能有抽象方法，也可能没有抽象方法。那位说，就跟没说一样，那抽象类和抽象方法都叫抽象，他们必定有关系，那关系是什么呢？如果一个类中有抽象方法，它必须得是抽象类。

An abstract class may have no abstract method，such as the following class Car. 马克- t o --wi n： At this time,the only point and the meaning of abstract class is that we can not instantiated the class, because it is abstract class.Why an abstract class can have a nonabstract method? what is the point? also in logic, think over the following example, car is a bit abstract in that you dont' know exactly whether it is a truck or a jeep or a limersine, 马克-to-win：so it is defined as a abstract class. but no matter whether it is truck,jep, or limersine, it definitely use steering wheel. so its steer() method is an ordinary method instead of an abstract method. ) Abstract class can’t be instantiated.

例1.7.1
abstract class Nothing {//里面有方法也照样声明为abstract
    void nothing() {
        System.out.println("nothing");
    }
}
abstract class VehMark_to_win {
    abstract void steer();
    abstract void move();
}
class Bike extends VehMark_to_win {//Bike不是抽象的，所以必须得全部实现abstract方法
。。。。。。。。。。。。。。。
详情请见：http://www.mark-to-win.com/JavaBeginner/JavaBeginner3_web.html#RelationAbstractMethodClass

0 0