static

[anurudh]

Please tell me final answer in yes or no of tis question
that "Static method can be overiden"
Although i have seen that if i create an object using reference of superclass superclass method is called.
Anurudh

[Danish Shaukat]

Hi!
YES, static methods can be overridden.
You cannot override a static method to be non-static.
A static method does not have this.
A static method cavn only call static methods of its class
A static method can only access static data of its class.
Regards
Danish Shaukat

[Thomas Paul]

Example:

public class Static1 {
    
    public static void method1() {
        System.out.println("Static1:method1");
    }
}
public class Static2 extends Static1 {
    
    public static void method1() {
        System.out.println("Static2:method1");
    }
}
public class StaticTester {
    
    public static void main(String[] args) {
        
        Static1.method1();
        Static2.method1();
    }
}

Try running this example for yourself. The result is:
Static1:method1
Static2:method1
So we can see that class Static2 has successfully overridden method1 of Static1.

[Jane Griscti]

Hi Danish, Thomas ...
Thomas, your example does compile and run but technically a static method cannot be overridden ... it's actually hidden.

If a class declares a static method, then the declaration of that method is said to hide any and all methods with the same signature in the superclasses and superinterfaces of the class that would otherwise be accessible to code in the class. A compile-time error occurs if a static method hides an instance method.
JLS�8.4.6.2

It's a fine point, not sure wether it would come into play in the Exam but just in case
Also, you can't reference the hidden method from an instance of the subclass.

------------------
Jane
The cure for boredom is curiosity.
There is no cure for curiosity.
-- Dorothy Parker
[This message has been edited by Jane Griscti (edited November 30, 2000).]

[Thomas Paul]

Interesting, but it isn't clear, at least to me, what the difference is between hidden and overridden. For example:

class Static2 extends Static1 {
    public static void method1() {
        Static1.method1();
        System.out.println("Static2:method1");
    }
}

Will run method1 of Static1 exactly as one would think. So what has been hidden and from whom?

[Paul Anilprem]

Basically, the concept is of polymorphism. Overriding is just a way to achieve it.
Base b = new SubClass();
b.m1(); //here subclass's m1() should be called as the actual object is of class SubClass.
Now, static methods and fields do not take part in polymorphism.
ie. Base.sm1(); will call Base's static method and SubClass.sm1() will call SubClass's static method (as you would expect). But the interesting point is b.sm1() will call Base's method even though the object is of class SubClass. That's why it is said that static methods are not overidden but are hidden.
Hidden means you can go behind the curtain and can access the hidden thing. Ex.
SubClass s = new SubClass();
s.sm1(); // will call SubClass's static method.
s.m1(); // will call SubClass's instance method.
( (Base) s ).sm1(); // will call base's static method.
( (Base) s ).m1(); // will STILL call Subclass's instance method. There is no going behind the curtains!
HTH,
Paul.

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[anurudh]

Thanks for your help it helped to make me build my concept
Anurudh