Java Api Core.initializeSession locale argument

What should the locale argument of the Core.initializeSession method in the Java Api be used for? It seems to expect a UUID in String format, but I haven't been able to find any documentation about what UUID's can be used and what the effect would be when supplying a locale here? Would this override the user's default language?
1 answers

See the SSO module for the use of this call. You can simply use:

session = Core.initializeSession(context, user, null, null);