/** * Message headers consist of standard HTTP message headers and custom headers. This method * assumes that all header entries that were not initially mapped by header mapper implementations * are custom headers. * * @param httpHeaders all message headers in their pre nature. * @param mappedHeaders the previously mapped header entries (all standard headers). * @return */ private Map<String, String> getCustomHeaders( HttpHeaders httpHeaders, Map<String, ?> mappedHeaders) { Map<String, String> customHeaders = new HashMap<String, String>(); for (Entry<String, List<String>> header : httpHeaders.entrySet()) { if (!mappedHeaders.containsKey(header.getKey())) { customHeaders.put( header.getKey(), StringUtils.collectionToCommaDelimitedString(header.getValue())); } } return customHeaders; }