private static @NotNull Pair<String,String> decodeFileName(@NotNull String fileName) {
    String name = fileName;
    String ext = "";
    String nameExtDelimiter = fileName.contains(ENCODED_NAME_EXT_DELIMITER) ? ENCODED_NAME_EXT_DELIMITER : ".";
    int extIndex = fileName.lastIndexOf(nameExtDelimiter);
    if (extIndex >= 0) {
      name = fileName.substring(0, extIndex);
      ext = fileName.substring(extIndex + nameExtDelimiter.length());
    }
    return new Pair<>(name, ext);
  }
private static @NotNull Pair<String,String> decodeFileName(@NotNull String fileName)