@SuppressWarnings("unchecked")
public Collection<Group> findGroupsOfUser(String user) throws Exception
{
MembershipHandler membershipHandler = orgService.getMembershipHandler();
List<Membership> members = (List<Membership>)membershipHandler.findMembershipsByUser(user);
List<Group> groups = new ArrayList<Group>();
for (Membership member : members)
{
Group g = findGroupById(member.getGroupId());
if (g != null && !hasGroup(groups, g))