private int generateMessageImage(TwitterBoardNotification notification) throws Exception {
   return generateMessageImage(
       notification.getMessage(),
       notification.getKeywords(),
       notification.getAuthor(),
       CUSTOM_FILE_NAME);
 }
 @Override
 public void onNotification(String id, TwitterBoardNotification notification) {
   LOG.info("Notification for topic id [{}] received.", id);
   LOG.info("Notification body: {}", notification.getMessage());
   try {
     this.queue.put(notification);
   } catch (InterruptedException e) {
     LOG.info("Failed to put notification to queue {}", notification.getMessage(), e);
   }
   updates.add(TwitterBoardUpdate.newNotification());
 }