presto-main/src/main/java/io/prestosql/type/IntervalYearMonthType.java/IntervalYearMonthType/getObjectValue
class IntervalYearMonthType:    @Override
    public Object getObjectValue(ConnectorSession session, Block block, int position)
    {
        if (block.isNull(position)) {
            return null;
        }
        return new SqlIntervalYearMonth(block.getInt(position, 0));
    }