code: public static AspectranWebService create(WebActivityServlet servlet, AspectranWebService rootService) {
          ServletContext servletContext = servlet.getServletContext();
          ServletConfig servletConfig = servlet.getServletConfig();
          String aspectranConfigParam = servletConfig.getInitParameter(ASPECTRAN_CONFIG_PARAM);
          if (aspectranConfigParam != null) {
              AspectranWebService service = create(servletContext, aspectranConfigParam);
              servletContext.setAttribute(STANDALONE_WEB_SERVICE_ATTRIBUTE_PREFIX +
                      servlet.getServletName(), service);
              return service;
          } else {
              return rootService;
          }
      }
docs: Returns a new instance of {@code AspectranWebService}.
  
  @param servlet the servlet
  @param rootService the root service
  @return the instance of {@code AspectranWebService}