code: void close() {
      shuttingDown = true;
      // shutdown thread pools
      dispatcherExecutor.shutdownNow();
      moverExecutor.shutdownNow();
      // close the output file
      IOUtils.closeStream(out);
      if (fs != null) {
        try {
          fs.delete(BALANCER_ID_PATH, true);
        } catch(IOException ignored) {
        }
      }
    }
docs: Close the connection.