The Set returned by Subject.getPrincipals(Class) has a couple problems. The toString() and toArray() methods don't include all the principals, but instead leave some out and duplicate others.

See attached test case, which produces the following output:

Tim missing in result string: [JAASBug2$MyPrincipal1@10595[Bob], JAASBug2$MyPrincipal1@10595[Bob]]
Tim not in array: [Ljava.security.Principal; { JAASBug2$MyPrincipal1@10595[Bob], JAASBug2$MyPrincipal1@10595[Bob] }