docs: public HttpServerExchange setResponseCookie(final Cookie cookie) {
          if(getConnection().getUndertowOptions().get(UndertowOptions.ENABLE_RFC6265_COOKIE_VALIDATION, UndertowOptions.DEFAULT_ENABLE_RFC6265_COOKIE_VALIDATION)) {
              if (cookie.getValue() != null && !cookie.getValue().isEmpty()) {
                  Rfc6265CookieSupport.validateCookieValue(cookie.getValue());
              }
              if (cookie.getPath() != null && !cookie.getPath().isEmpty()) {
                  Rfc6265CookieSupport.validatePath(cookie.getPath());
              }
              if (cookie.getDomain() != null && !cookie.getDomain().isEmpty()) {
                  Rfc6265CookieSupport.validateDomain(cookie.getDomain());
              }
          }
          if (responseCookies == null) {
              responseCookies = new TreeMap<>(); //hashmap is slow to allocate in JDK7
          }
          responseCookies.put(cookie.getName(), cookie);
          return this;
      }