if (q.getUserName() != null) {
qb.idFilter(q.getUserName());
}
if (q.getEmail() != null) {
qb.attributeValuesFilter(UserDAOImpl.USER_EMAIL, new String[] { q.getEmail() });
}
if (q.getFirstName() != null) {
qb.attributeValuesFilter(UserDAOImpl.USER_FIRST_NAME, new String[] { q.getFirstName() });
}