public void notContainsInheritanceABuilder() {
PersistenceManager pm = pmf.getPersistenceManager();
pm.currentTransaction().begin();
//add newsgroup_0 -> [user_0and2]
NewsGroup ng0 = new NewsGroup("newsgroup_0");
Collection users = ng0.getUsers();
users.add(commonUser);
pm.makePersistent(ng0);
//add newsgroup_1 -> [user_1]
NewsGroup ng1 = new NewsGroup("newsgroup_1");
users = ng1.getUsers();
users.add(new GroupUser("user_1"));
pm.makePersistent(ng1);
pm.currentTransaction().commit();
pm.close();
}