Rules round up doubt.

[Aparanji Raju]

Hi All,
Can some body please explain the following qn from rules round up?
"If a final variable is a reference to an object, can the object's data member be modified while the program is running?"
What does "final variable is a reference to an object mean"?
I think i have seen this question being answered somewhere in the forum,but I dont exactly remember.Please help me by either giving a reference to that site or an explaination.
Thanks.
bye,
Aparanji

[Ajith Kallambella]

Aparanji,
Perhaps the following code helps you understand the concept. If not, shout back!

// Some dummy class for the demo
class Holder
{
    public int i = 10 ;
}
public class FinalObjReference
{
    public static void main( String[] s)
    {
        // Declare a final variable which is an object reference.
        final Holder h = new Holder();
        
        System.out.println( h.i ) ;
        
        // This is not valid as you are trying to change the reference
        // held by h
        h = new Holder();
        
        // ..however you can change the contents of the object held by
        // the reference. This is perfectly valid because h is still 
        // pointing to the same object.
        h.i += 9 ;
        
        // Dump the value in h to confirm the change did take place.
        System.out.println( h.i ) ;
        
    }
}

Ajith

[Aparanji Raju]

Thank you Ajith.
It is clear to me now that I cant change/create a new address when i have a final object reference,but can change its contents.
Thanks again.
Aparanji.