Java 多态性
本教程将介绍Java 多态性的处理方法,这篇教程是从别的地方看到的,然后加了一些国外程序员的疑问与解答,希望能对你有所帮助,好了,下面开始学习吧。
问题描述
This is a question just out of curiosity.
I know that when we call a subclass object's overridden method by the reference of it's superclass, JVM gives importance to the type of object and not to type of reference.
This is my simple code :
class Animal
{
void eat()
{
System.out.println("Animal is eating...");
}
}
class Horse extends Animal
{
@Override
void eat()
{
System.out.println("Horse is eating...");
}
}
public class PolymorphismTest
{
public static void main(String...args)
{
Animal a=new Animal();
a.eat();
Animal h= new Horse();
h.eat();
}
}
As expected, I get the output :
run:
Animal is eating...
Horse is eating...
BUILD SUCCESSFUL (total time: 0 seconds)
Now my question is ,
Is there any way that we can use reference h to call the superclass eat() method and not the subclass one? I know this is a question that is somewhat against the laws of polymorphism but you never know when the need may arise to do so.
I tried to typecast the reference h to Animal but no luck. Any ideas?
解决方案
class Horse extends Animal
{
@Override
void eat()
{
super.eat();
}
}
好了关于Java 多态性的教程就到这里就结束了,希望趣模板源码网找到的这篇技术文章能帮助到大家,更多技术教程可以在站内搜索。