public static boolean hasNullField(Object[] row) {
    if (row == null) {
      return true;
    }
    for (int i = 0; i < row.length - 1; i++) {
      if (row[i] == null) {
        return true;
      }
    }
    return false;
  }
this method checks whether the row returned by IUDFInputDataSet.nextRowInObjects() has any null
fields except the timestamp

@param row the returned row by calling {@link IUDFInputDataSet#nextRowInObjects()}
@return true if any row field is null.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/transformation/dag/util/InputRowUtils.java