private static final String CONTENT_DISPOSITION = "content-disposition";
private static final String FILENAME_KEY = "filename=";
private static final String FILENAME_WITH_CHARSET_KEY = "filename*=";

private void parseRequest(HttpServletRequest request) {
  try {
    Collection<Part> parts = request.getParts();
    this.multipartParameterNames = new LinkedHashSet<String>(parts.size());
    MultiValueMap<String, MultipartFile> files = new LinkedMultiValueMap<String, MultipartFile>(parts.size());
    for (Part part : parts) {
      String disposition = part.getHeader(CONTENT_DISPOSITION);
      String filename = extractFilename(disposition);
      if (filename == null) {
        filename = extractFilenameWithCharset(disposition);
      }
      if (filename != null) {
        files.add(part.getName(), new StandardMultipartFile(part, filename));
      } else {
        this.multipartParameterNames.add(part.getName());
      }
    }
    setMultipartFiles(files);
  }
    catch (Throwable ex) {
      throw new MultipartException("Could not parse multipart servlet request", ex);
    }
  }

private String extractFilename(String contentDisposition) {
  return extractFilename(contentDisposition, FILENAME_KEY);
}