docs: public NotificationSettings readNotificationSettings(InputStream in) throws ConversionException, IOException {
          JSONObject json = parseObject(in);
          NotificationSettings ret = new NotificationSettings();
          ret.deliveryInterval = readIntInternal(json.get(N_DELIVERYINTERVAL));
          ret.inboxExpiry = readIntInternal(json.get(N_INBOXEXPIRY));
          return ret;
      }