* @throws IOException if an I/O error occurs
   */
  public static ImmutableList<Path> listFiles(Path dir) throws IOException {
    try (DirectoryStream<Path> stream = Files.newDirectoryStream(dir)) {
      return ImmutableList.copyOf(stream);
    } catch (DirectoryIteratorException e) {
      throw e.getCause();
    }
  }

  /**

        }
    }

    private void loadPersistedHandles() {
        if (!Files.exists(stateDirectory)) {
            return;
        }

        try (DirectoryStream<Path> stream = Files.newDirectoryStream(stateDirectory, "*.handle")) {
            for (Path handleFile : stream) {
                try (ObjectInputStream ois = new ObjectInputStream(Files.newInputStream(handleFile))) {

        } catch (IOException e) {
            log.error("Failed to remove persisted handle", e);
        }
    }
    
    private void loadPersistedHandles() {
        try (DirectoryStream<Path> stream = Files.newDirectoryStream(
                stateDirectory, "*.handle")) {
            for (Path handleFile : stream) {
                try (ObjectInputStream ois = new ObjectInputStream(