### Question:
HibernateUserDAO extends HibernatePersistentObjectDAO<User> implements UserDAO { @Override public boolean delete(long userId, int code) { return delete(userId, null); } private  HibernateUserDAO(); static boolean ignoreCaseLogin(); @Override boolean delete(long userId, int code); @Override List<User> findByName(String name); @Override User findByUsername(String username); @Override User findByUsernameIgnoreCase(String username); List<User> findByLikeUsername(String username); @Override List<User> findByUsernameAndName(String username, String name); @Override boolean store(User user); @Override boolean store(User user, UserHistory transaction); boolean validateUser(String username, String password); @Override boolean validateUser(String username); int getPasswordTtl(); @Override boolean isPasswordExpired(String username); @Override int count(Long tenantId); @Override int countGuests(Long tenantId); @Override boolean delete(long userId, UserHistory transaction); UserHistoryDAO getUserHistoryDAO(); void setUserHistoryDAO(UserHistoryDAO userHistoryDAO); void setUserListenerManager(UserListenerManager userListenerManager); UserListenerManager getUserListenerManager(); @Override void initialize(User user); @Override Map<String, Generic> findUserSettings(long userId, String namePrefix); void setGenericDAO(GenericDAO genericDAO); @Override User findAdminUser(String tenantName); void setConfig(ContextProperties config); @Override Set<User> findByGroup(long groupId); @Override User findById(long id); @Override User getUser(String username);  }### Answer:
@Test public void testDelete() throws PersistenceException { User user = dao.findByUsername("author"); Assert.assertEquals(2, user.getGroups().size()); dao.delete(user.getId()); user = dao.findByUsername("author"); Assert.assertNull(user); User testUser = dao.findByUsername("test"); Assert.assertEquals(2, testUser.getGroups().size()); testUser.removeGroupMemberships(null); dao.store(testUser); dao.initialize(testUser); Assert.assertEquals(1, testUser.getGroups().size()); String name = testUser.getUserGroupName(); Assert.assertTrue(dao.delete(testUser.getId())); user = dao.findByUsername("test"); Assert.assertNull(user); Assert.assertNull(groupDao.findByName(name, 1)); Group group = groupDao.findByName("guest", 1); groupDao.initialize(group); Assert.assertFalse(group.getUsers().contains(testUser)); }