a question

[sasank manohar]

class Animal
{
static void doStuff()
{
System.out.print("a ");
}
}

class Dog extends Animal
{
static void doStuff() //redefinition,not overridden

{
System.out.println("Dog");
}
public static void main(String[] args)
{
Animal[] a={new Animal(),new Dog(),new Animal()};

for(int x=0;x<a.length;x++)
{
a[x].doStuff();
}
}
}

well the answer i got is "a a a" when i expected " a Dog a" where have i gone wrong

a[0].doStuff() becomes Animal.doStuff() which becomes 'a'
a[1].doStuff() becomes dog.doStuff() which becomes 'Dog'
a[2].doStuff() becomes Animal.doStuff() which becomes 'a'

this is my interpretation but evidently i have gone wrong but where ?

[Ankit Garg]

Static methods are called on the type of the reference on which the method is called and not the type of the object stored in the reference stored in the object....

For eg.

class Base
{
    static void hello(){System.out.println("Hello!");}
}
class Derived extends Base
{
    static void hello(){System.out.println("Bye!");}
}
class MainClass
{
    public static void main(String[] args)
    {
         Base obj = new Derived();
         obj.hello();    //displays Hello!
    }
}

this is because after compilation the main method would look as
Base obj = new Derived();
Base.hello(); //displays Hello!

As you can see that the compiler replaces the name of the object with the name of the type of the reference with which the method was called. This happens only in case of static methods....

[Vinod Kumar Kommineni]

Basically we can't override an static method. In this example it is hiding not overriding.I you override a method you will get the benefits of run-time polymorphism,if you hide it you wont.
Since polymorphism does not work you will get a a a instead of a Dog a .

[sasank manohar]

Thank you guys !!
[ August 12, 2008: Message edited by: sri dev ]