code: @Override
    public void onTimer(String timerName) {
      if (timerName.equals(IDLE_SESSION_TIMER_NAME)) {
        checkIdleAppSession();
      }
      else if (timerName.equals(TX_TIMER_NAME)) {
        new TxTimerTask(this, sessionData.getTxTimerRequest()).run();
      }
      else {
        logger.warn("Received an unknown timer '{}' for Session-ID '{}'", timerName, getSessionId());
      }
    }
docs: /* (non-Javadoc)
  @see org.jdiameter.common.impl.app.AppSessionImpl#onTimer(java.lang.String)