@Override
  public void close() throws SQLException {
    RequestDelegate<Void> delegate = createRequestDelegate();
    for (ResultSet rs : resultSets) {
      delegate.addRequest(
          () -> {
            rs.close();
            return null;
          });
    }
    delegate.requestAll();
  }
The implementation of {@link ClusterTestResultSet} in cluster test.
integration-test/src/main/java/org/apache/iotdb/itbase/runtime/ClusterTestResultSet.java