final void close() throws IOException {
    if (!closed) {
      if (fieldsStream != null) {
        fieldsStream.close();
      }
      if (isOriginal) {
        if (cloneableFieldsStream != null) {
          cloneableFieldsStream.close();
        }
        if (cloneableIndexStream != null) {
          cloneableIndexStream.close();
        }
      }
      if (indexStream != null) {
        indexStream.close();
      }
      fieldsStreamTL.close();
      closed = true;
    }
  }