code: public boolean startInactivityTimer (Transaction t, InactivityTimer iat)
      {
          if (t != null)
              return ((EmbeddableTransactionImpl) t).startInactivityTimer(iat);
  
          return false;
      }
docs: Start an inactivity timer and call alarm method of parameter when
  timeout expires.
  Returns false if transaction is not active.
  
  @param t    Transaction associated with this timer.
  @param iat  callback object to be notified when timer expires.
  @return     boolean to indicate whether timer started