presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/RaptorPageSourceProvider.java/RaptorPageSourceProvider/createPageSource
class RaptorPageSourceProvider:    private ConnectorPageSource createPageSource(
            UUID shardUuid,
            OptionalInt bucketNumber,
            List<ColumnHandle> columns,
            TupleDomain<RaptorColumnHandle> predicate,
            OrcReaderOptions orcReaderOptions,
            OptionalLong transactionId)
    {
        List<RaptorColumnHandle> columnHandles = columns.stream().map(RaptorColumnHandle.class::cast).collect(toList());
        List<Long> columnIds = columnHandles.stream().map(RaptorColumnHandle::getColumnId).collect(toList());
        List<Type> columnTypes = columnHandles.stream().map(RaptorColumnHandle::getColumnType).collect(toList());

        return storageManager.getPageSource(shardUuid, bucketNumber, columnIds, columnTypes, predicate, orcReaderOptions, transactionId);
    }