presto-blackhole/src/main/java/io/prestosql/plugin/blackhole/BlackHolePageSourceProvider.java/BlackHolePageSourceProvider/createPageSource
class BlackHolePageSourceProvider:    @Override
    public ConnectorPageSource createPageSource(
            ConnectorTransactionHandle transactionHandle,
            ConnectorSession session,
            ConnectorSplit split,
            ConnectorTableHandle tableHandle,
            List<ColumnHandle> columns)
    {
        BlackHoleTableHandle table = (BlackHoleTableHandle) tableHandle;

        ImmutableList.Builder<Type> builder = ImmutableList.builder();

        for (ColumnHandle column : columns) {
            builder.add(((BlackHoleColumnHandle) column).getColumnType());
        }
        List<Type> types = builder.build();

        Page page = generateZeroPage(types, table.getRowsPerPage(), table.getFieldsLength());
        return new BlackHolePageSource(page, table.getPagesPerSplit(), executorService, table.getPageProcessingDelay());
    }