code: public void stopSession() throws SIException {
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.entry(this, tc, "stopSession");
          mainConsumer.getConsumerSession().stop();
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.exit(this, tc, "stopSession");
      }
docs: Stops the main consumer session so that we can be sure
  that no more messages will be delivered.
  
  @throws SIException