code: public String buildRequestUrl() {
      StringBuilder sb = new StringBuilder();
      sb.append(buildServletPath());
      if (null != pathInfo) {
        sb.append(pathInfo);
      }
      if (null != queryString) {
        sb.append('?').append(queryString);
      }
      return sb.toString();
    }
docs: Returns request Url contain pathinfo and queryString but without contextPath.