This week's book giveaway is in the Security forum.We're giving away four copies of Penetration Testing Basics and have Ric Messier on-line!See this thread for details.
Win a copy of Penetration Testing Basics this week in the Security forum!

Final variables in switch

Seema Ahuja
Ranch Hand
Posts: 32
I hv a doubt here.

we all know that final variables cannot be changed.

so how come the following code works?

can anyone please tell me why is it letting me modify the final variable x??

Thanks

steven gerrard
Ranch Hand
Posts: 55
ur not modifying the final variable
since x is final x-1 is another final
value of x does not change
its like saying
case (y=x-1):

Greenhorn
Posts: 5
hi
here final valued not changed;

class vignesh
{
public static void main(String[] args) throws Exception
{
final int x =2;
for(int z =0;z<4;z++)
{
switch(x)
{
case x: System.out.println("One");break;
case x-1: System.out.println("two");break;
case x-2: System.out.println("zero");
}
}
}
}

o/p:
one
one
one
one

Sumit Jain
Greenhorn
Posts: 9
Basically, key word final is acting a constant to a variable.
so ,final int x =2; means x = 2 and is fixed(Const)through out the code.

Now for case x: //nothing but x=2;
case x-1://it will not assign the value to x but it wiil evalute as (2-1) = 1.
case x-2://same as above except evalute as (2-2) = 0.

So, In a nutcell you can't modify the value of x but you can use it for any mathematical expression as constant.

Hope It will help.
Regards,
Sumit Jain