For a Singleton class, is it a good idea to keep String constants (used internally in the member functions) as
private static final
There is not much difference between those, only that the
private static final String gets initialized when the program gets initialized, the
private final String gets initialized when the Singletons instance is being created.
The only advantage of the
static String is, is that you can use it in static methods too (if you need them)
Also there are no performance issues with both of them, as both variables won't get garbage collected as long as the program is running.