docs: protected void parseRoutingCodeHeader() {
  
          String rtCode = this.request.getHeader(RestMessageHeaders.X_VOLD_ROUTING_TYPE_CODE);
          if(rtCode != null) {
              try {
                  int routingTypeCode = Integer.parseInt(rtCode);
                  this.parsedRoutingType = RequestRoutingType.getRequestRoutingType(routingTypeCode);
              } catch(NumberFormatException nfe) {
                  logger.error("Exception when validating request. Incorrect routing type parameter. Cannot parse this to long: "
                                       + rtCode,
                               nfe);
                  RestErrorHandler.writeErrorResponse(this.messageEvent,
                                                      HttpResponseStatus.BAD_REQUEST,
                                                      "Incorrect routing type parameter. Cannot parse this to long: "
                                                              + rtCode);
              } catch(VoldemortException ve) {
                  logger.error("Exception when validating request. Incorrect routing type code: "
                               + rtCode, ve);
                  RestErrorHandler.writeErrorResponse(this.messageEvent,
                                                      HttpResponseStatus.BAD_REQUEST,
                                                      "Incorrect routing type code: " + rtCode);
              }
          }
      }