code: private void doFilterHttp(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
          throws IOException, ServletException {
  
          request.setAttribute(ARQUILLIAN_MANAGER_ATTRIBUTE, manager);
  
          boolean isDelegated = delegator.tryDelegateRequest(request, response, filterChain);
  
          if (!isDelegated) {
              doFilterWarp(request, response, filterChain);
          }
      }
docs: <p>
  Checks whether the request processing can be delegated to one of registered {@link RequestDelegationService}s.
  </p>
  <p>
  <p>
  If not, delegates processing to {@link #doFilterWarp(HttpServletRequest, HttpServletResponse, FilterChain)}.
  </p>