private Notification convert(final NotificationEvent event) {

    final Notification notification = new Notification();
    notification.setNodeUrn(new NodeUrn(event.getNodeUrn()));
    notification.setTimestamp(new DateTime(event.getTimestamp()));
    notification.setMsg(event.getMessage());

    return notification;
  }
  @Override
  public int compare(NotificationEvent notificationEvent1, NotificationEvent notificationEvent2) {

    if (notificationEvent1.equals(notificationEvent2)) {
      return 0;
    }

    long value = notificationEvent1.getDeliverBy() - notificationEvent2.getDeliverBy();

    if (value == 0) {
      value = notificationEvent1.getTimestamp() - notificationEvent2.getTimestamp();
    }

    if (value == 0) {
      value = notificationEvent1.hashCode() - notificationEvent2.hashCode();
    }

    if (_ascending) {
      return (int) value;
    } else {
      return (int) -value;
    }
  }