Java 多态性 [英] Java Polymorphism

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();
    }
}

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