docs: protected void createDir(String dir) throws StatefulStorageException {
      Path path = new Path(dir);
  
      try {
        fileSystem.mkdirs(path);
        if (!fileSystem.exists(path)) {
          throw new StatefulStorageException("Failed to create dir: " + dir);
        }
      } catch (IOException e) {
        throw new StatefulStorageException("Failed to create dir: " + dir, e);
      }
    }