Complie time Constant - final int a; a =1 ; IS NOT?!

[Ajay Chandravadiya]

Hi,
As per the book and the compiler following is true.

final int a = 1;
final int b;
b = 2;
int x = 0;
switch (x) {
  case a:     // ok
  case b:     // compiler error

Q. Why 'b' variable is NOT a Compile Time Constant?

[ahmed yehia]

The rule for a 'case' is compile- time constants, and variable 'b' isnt considered so, its assigned a value later hence not become compile time constant.
You would have to declare and inialize the final variable in 1 line, like this:

   
final int b = 2; 

[Lucky J Verma]

variable a is given value at compilation time only so its compile time constant
but variable b is not getting any value till it runs.so run time value assigned.
so not comiple time constant