byte a = 125;
final byte b = 2;
final Byte c = 3;
switch (a) {
case b: // works fine
    break;
case c: // Constant Expression required
    break;
}
Since cis a final variable, isn't it a compile time constant and hence a valid case label?
 
  
                     
                        
Since c is a final variable, isn't it a compile time constant
No. The rules for constant expressions are given in JLS 15.28, and they don't include wrapper types:
A constant expression is an expression denoting a value of primitive type or a String that does not complete abruptly and is composed using only the following [...]
A wrapper type is neither a primitive type nor String.
 
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