docs: public static boolean streamNotConsumed( HttpServletRequest request ) {
          try {
              ServletInputStream servletInputStream = request.getInputStream();
              //in servlet >= 3.0, available will throw an exception (while previously it didn't)
              return request.getContentLength() != 0 && servletInputStream.available() > 0;
          } catch (IOException e) {
              return false;
          }
      }