docs: public void setSessionId(short sessionId)
     {
        if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) SibTr.entry(this, tc, "setSessionId", ""+sessionId);
        if (this.sessionId == 0 && sessionId != 0)
        {
           this.sessionId = sessionId;
        }
        else
        {
           // If the session Id is being set twice this is badness. The conversation helper is
           // associated one to one to a proxy queue, that in turn is associated one to one with a
           // consumer session. They aren't re-used, so calling this twice indicates some bug.
           SIErrorException e = new SIErrorException(
              nls.getFormattedMessage("SESSION_ID_HAS_ALREADY_BEEN_SET_SICO1045", null, null)
           );
  
           FFDCFilter.processException(e, CLASS_NAME + ".setSessionId",
                                       CommsConstants.CONVERSATIONHELPERIMPL_11, this);
  
           if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()) SibTr.debug(this, tc, e.getMessage(), e);
  
           throw e;
        }
        if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) SibTr.exit(this, tc, "setSessionId");
     }