code: protected void addRequestCookies(final HttpServletRequest httpServletRequest, final Map<String, List<Object>> attributes) {
          final Cookie[] cookies = httpServletRequest.getCookies();
          if (cookies == null) {
              return;
          }
  
          for (final Cookie cookie : cookies) {
              final String cookieName = cookie.getName();
              if (this.cookieAttributeMapping.containsKey(cookieName)) {
                  for (final String attributeName : this.cookieAttributeMapping.get(cookieName)) {
                      attributes.put(attributeName, list(cookie.getValue()));
                  }
              }
          }
      }
docs: Add request cookies to the attributes map
  
  @param httpServletRequest Http Servlet Request
  @param attributes Map of attributes to add additional attributes to from the Http Request