docs: public IServletConfig getServletInfo(String string) {
          if (string == null || string.isEmpty()){
              Tr.debug(tc, "getServletInfo", "servlet name is null/empty. Use internal servlet name " + NULLSERVLETNAME);
              string = NULLSERVLETNAME;
          }
  
          return (IServletConfig) this.servletInfo.get(string);
      }