@Override
public List<User> listByUserGroup(UserGroup userGroup) {
JPAQuery query = new JPAQuery(getEntityManager());
QUser qUser = QUser.user;
QUserGroup qUserGroup = QUserGroup.userGroup;
query.from(qUser)
.join(qUser.groups, qUserGroup)
.where(qUserGroup.eq(userGroup))
.orderBy(qUser.lastName.lower().asc(), qUser.firstName.lower().asc());
return query.list(qUser);
}