code: public static String getRelativePath(String path, String backupDirCanonicalPath) throws MalformedURLException
     {
        URL urlPath = new URL(resolveFileURL("file:" + path));
        URL urlBackupDir = new URL(resolveFileURL("file:" + backupDirCanonicalPath));
  
        return urlPath.toString().replace(urlBackupDir.toString() + "/", "");
     }
docs: Will be returned relative path {name}/{name}.xml for all OS.
  
  @param path
  String, path to
  @param backupDirCanonicalPath
  String, path to backup dir
  @return String
  Will be returned relative path {name}/{name}.xml for all OS
  @throws MalformedURLException