docs: public int getNumberOfActiveMessages()
    {
      if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
        SibTr.entry(tc, "getNumberOfActiveMessages");
      int returnValue = (int)_targetStream.countAllMessagesOnStream();
      if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
        SibTr.exit(tc, "getNumberOfActiveMessages", new Integer(returnValue));
      return returnValue;
    }