presto-blackhole/src/main/java/io/prestosql/plugin/blackhole/BlackHoleSplitManager.java/BlackHoleSplitManager/getSplits
class BlackHoleSplitManager:    @Override
    public ConnectorSplitSource getSplits(
            ConnectorTransactionHandle transaction,
            ConnectorSession session,
            ConnectorTableHandle table,
            SplitSchedulingStrategy splitSchedulingStrategy)
    {
        int splitCount = ((BlackHoleTableHandle) table).getSplitCount();
        return new FixedSplitSource(nCopies(splitCount, BlackHoleSplit.INSTANCE));
    }