presto-hive/src/main/java/io/prestosql/plugin/hive/util/HiveWriteUtils.java/SmallintFieldSetter/setField
class SmallintFieldSetter:        @Override
        public void setField(Block block, int position)
        {
            value.set(Shorts.checkedCast(SmallintType.SMALLINT.getLong(block, position)));
            rowInspector.setStructFieldData(row, field, value);
        }