presto-hive/src/main/java/io/prestosql/plugin/hive/util/HiveWriteUtils.java/TimestampFieldSetter/setField
class TimestampFieldSetter:        @Override
        public void setField(Block block, int position)
        {
            long millisUtc = TimestampType.TIMESTAMP.getLong(block, position);
            value.setTime(millisUtc);
            rowInspector.setStructFieldData(row, field, value);
        }