UserService { public String deleteUser(String id) { Key key = keyFactory.newKey(id); datastore.delete(key); return "ok"; } UserService(Datastore datastore, String kind); List<User> getAllUsers(); User createUser(String name, String email); String deleteUser(String id); User updateUser(String id, String name, String email);  }
@Test public void testDeleteUser() { String result = USER_SERVICE.deleteUser(USER_ID); assertEquals("ok", result); assertNull(DATASTORE.get(USER_KEY)); }