@Override
 public void unsubscribeFromTopic(Long topicId, boolean forceSync)
     throws UnavailableTopicException {
   checkClientState(State.STARTED, "Kaa client isn't started");
   notificationManager.unsubscribeFromTopic(topicId, forceSync);
 }
 @Override
 public void subscribeToTopics(List<Long> topicIds, boolean forceSync)
     throws UnavailableTopicException {
   checkClientState(State.STARTED, "Kaa client isn't started");
   notificationManager.subscribeToTopics(topicIds, forceSync);
 }