Case constant must be a compile time constant! : switch « Statements « SCJP

1. SCJP
2. Statements
3. switch

It is not enough to be final, it must be a compile time constant.

public class MainClass{
    public static void main(String[] argv){
        final int a = 1;
        final int b;
        b = 2;
        int x = 0;
        switch (x) {
          case a:     // ok
          case b:     // compiler error
        }
    }
}

Exception in thread "main" java.lang.Error: Unresolved compilation problem: 
	case expressions must be constant expressions

	at MainClass.main(MainClass.java:9)