/**
  * Gets the id of logged in user
  *
  * @return int|string
  */
 public function getUserId()
 {
     $token = $this->getSecurityContext()->getToken();
     if (!$token) {
         return null;
     }
     $user = $token->getUser();
     if (!is_object($user) || !is_a($user, $this->metadataProvider->getBasicLevelClass())) {
         return null;
     }
     return $this->objectIdAccessor->getId($user);
 }