presto-orc/src/main/java/io/prestosql/orc/reader/TimestampColumnReader.java/TimestampColumnReader/startStripe
class TimestampColumnReader:    @Override
    public void startStripe(ZoneId timeZone, InputStreamSources dictionaryStreamSources, ColumnMetadata<ColumnEncoding> encoding)
    {
        baseTimestampInSeconds = ZonedDateTime.of(2015, 1, 1, 0, 0, 0, 0, timeZone).toEpochSecond();

        presentStreamSource = missingStreamSource(BooleanInputStream.class);
        secondsStreamSource = missingStreamSource(LongInputStream.class);
        nanosStreamSource = missingStreamSource(LongInputStream.class);

        readOffset = 0;
        nextBatchSize = 0;

        presentStream = null;
        secondsStream = null;
        nanosStream = null;

        rowGroupOpen = false;
    }