code: private FileStatus versionBasedGetFileInfo(String src) throws IOException {
      if (namenodeVersion >= ClientProtocol.OPTIMIZE_FILE_STATUS_VERSION) {
        return HdfsFileStatus.toFileStatus(namenode.getHdfsFileInfo(src), src);
      } else {
        return namenode.getFileInfo(src);
      }
    }
docs: Get file info: decide which rpc to call based on protocol version