docs: public static ModelAndView writeError(final HttpServletResponse response, final String error) {
          val model = CollectionUtils.wrap(OAuth20Constants.ERROR, error);
          val mv = new ModelAndView(new MappingJackson2JsonView(MAPPER), (Map) model);
          mv.setStatus(HttpStatus.BAD_REQUEST);
          response.setStatus(HttpStatus.BAD_REQUEST.value());
          return mv;
      }