code: public final void setUserid(String value) {
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.entry(this, tc, "setUserid", value);
          getApi().setField(JsApiAccess.USERID, value);
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.exit(this, tc, "setUserid");
      }
docs: /*
  Set the contents of the Userid field in the message header.
  
  Javadoc description supplied by JsApiMessage interface.