visit.logout();
visit.clear();
    public void testLogin() {        User user = new User();        Visit visit = new Visit();        assertNull(visit.getUserId());        visit.login(user.getId(), false);        assertSame(user.getId(), visit.getUserId());        assertFalse(visit.isAdmin());        visit.login(user.getId(), true);        assertSame(user.getId(), visit.getUserId());        assertTrue(visit.isAdmin());        visit.logout();        assertNull(visit.getUserId());    }