code: protected void checkCacheControlHeaders(final Request request,
                                                     final HttpServletResponse servletResponse,
                                                     final FedoraResource resource,
                                                     final HttpSession session) {
          evaluateRequestPreconditions(request, servletResponse, resource, session, true);
          addCacheControlHeaders(servletResponse, resource, session);
      }
docs: Evaluate the cache control headers for the request to see if it can be served from
  the cache.
  
  @param request the request
  @param servletResponse the servlet response
  @param resource the fedora resource
  @param session the session