docs: @Override
      protected ModelAndView handleRequestInternal(final HttpServletRequest request, final HttpServletResponse response) throws Exception {
          for (val delegate : this.delegates) {
              if (delegate.canHandle(request, response)) {
                  return delegate.handleRequestInternal(request, response);
              }
          }
          return generateErrorView(CasProtocolConstants.ERROR_CODE_INVALID_REQUEST, null);
      }