private static @NotNull ContentHashEnumerator openContentHashEnumeratorOrCreateEmpty(@NotNull Path contentsHashesFile)
    throws IOException {
    try {
      return openContentHashEnumerator(contentsHashesFile);
    }
    catch (IOException e) {
      //No need to fail here: just clean contentHashes, and open empty -- content hashes could be re-build
      // by contentStorage data
      LOG.warn("ContentHashEnumerator is broken -- clean it, hope it will be recovered from ContentStorage later on. " +
               "Cause: " + e.getMessage());
      IOUtil.deleteAllFilesStartingWith(contentsHashesFile);
      return openContentHashEnumerator(contentsHashesFile);
    }
  }
private static @NotNull ContentHashEnumerator openContentHashEnumeratorOrCreateEmpty(@NotNull Path contentsHashesFile)