Just wanted some opinions on the matter. I have always used int flags, and was just curious on possible performance of ease of use if I were to use enumerations in Java?
I very much doubt you'd see performance benefits - and in some cases there may even be performance penalties, depending on how you're using them. I doubt they'd be significant though.
The benefit isn't in terms of performance - it's in terms or expressing your intentions more clearly, leading to more readable (and type-safe) code. For example, with integer flags nothing's going to complain if you try to use (say) HTTP_STATUS_UNAUTHORIZED as a value for your file sharing mode in a method call... whereas if both of those were enums, the parameter would be strongly typed to really only allow file sharing modes (or null, admittedly, assuming you are talking about Java).