public function fetch()
    {
        $sessionToken = null;
        if (AVUser::getCurrentUser())
        {
            $sessionToken = AVUser::getCurrentUser()->getSessionToken();
        }
        $response = AVClient::_request('GET', '/classes/' . $this->className . '/' . $this->objectId, $sessionToken);
        $this->_mergeAfterFetch($response);
    }