presto-benchmark/src/main/java/io/prestosql/benchmark/HashBuildAndJoinBenchmark.java/HashBuildAndJoinBenchmark/createDrivers
class HashBuildAndJoinBenchmark:    @Override
    protected List<Driver> createDrivers(TaskContext taskContext)
    {
        ImmutableList.Builder<OperatorFactory> driversBuilder = ImmutableList.builder();
        driversBuilder.add(ordersTableScan);
        List<Type> sourceTypes = ordersTableTypes;
        OptionalInt hashChannel = OptionalInt.empty();
        if (hashEnabled) {
            driversBuilder.add(createHashProjectOperator(1, new PlanNodeId("test"), sourceTypes));
            sourceTypes = ImmutableList.<Type>builder()
                    .addAll(sourceTypes)
                    .add(BIGINT)
                    .build();
            hashChannel = OptionalInt.of(sourceTypes.size() - 1);
        }

        // hash build
        JoinBridgeManager<PartitionedLookupSourceFactory> lookupSourceFactoryManager = JoinBridgeManager.lookupAllAtOnce(new PartitionedLookupSourceFactory(
                sourceTypes,
                ImmutableList.of(0, 1).stream()
                        .map(sourceTypes::get)
                        .collect(toImmutableList()),
                Ints.asList(0).stream()
                        .map(sourceTypes::get)
                        .collect(toImmutableList()),
                1,
                requireNonNull(ImmutableMap.of(), "layout is null"),
                false));
        HashBuilderOperatorFactory hashBuilder = new HashBuilderOperatorFactory(
                2,
                new PlanNodeId("test"),
                lookupSourceFactoryManager,
                ImmutableList.of(0, 1),
                Ints.asList(0),
                hashChannel,
                Optional.empty(),
                Optional.empty(),
                ImmutableList.of(),
                1_500_000,
                new PagesIndex.TestingFactory(false),
                false,
                SingleStreamSpillerFactory.unsupportedSingleStreamSpillerFactory());
        driversBuilder.add(hashBuilder);
        DriverFactory hashBuildDriverFactory = new DriverFactory(0, true, false, driversBuilder.build(), OptionalInt.empty(), UNGROUPED_EXECUTION);

        // join
        ImmutableList.Builder<OperatorFactory> joinDriversBuilder = ImmutableList.builder();
        joinDriversBuilder.add(lineItemTableScan);
        sourceTypes = lineItemTableTypes;
        hashChannel = OptionalInt.empty();
        if (hashEnabled) {
            joinDriversBuilder.add(createHashProjectOperator(1, new PlanNodeId("test"), sourceTypes));
            sourceTypes = ImmutableList.<Type>builder()
                    .addAll(sourceTypes)
                    .add(BIGINT)
                    .build();
            hashChannel = OptionalInt.of(sourceTypes.size() - 1);
        }

        OperatorFactory joinOperator = LOOKUP_JOIN_OPERATORS.innerJoin(
                2,
                new PlanNodeId("test"),
                lookupSourceFactoryManager,
                sourceTypes,
                Ints.asList(0),
                hashChannel,
                Optional.empty(),
                OptionalInt.empty(),
                unsupportedPartitioningSpillerFactory());
        joinDriversBuilder.add(joinOperator);
        joinDriversBuilder.add(new NullOutputOperatorFactory(3, new PlanNodeId("test")));
        DriverFactory joinDriverFactory = new DriverFactory(1, true, true, joinDriversBuilder.build(), OptionalInt.empty(), UNGROUPED_EXECUTION);

        Driver hashBuildDriver = hashBuildDriverFactory.createDriver(taskContext.addPipelineContext(0, true, false, false).addDriverContext());
        hashBuildDriverFactory.noMoreDrivers();
        Driver joinDriver = joinDriverFactory.createDriver(taskContext.addPipelineContext(1, true, true, false).addDriverContext());
        joinDriverFactory.noMoreDrivers();

        return ImmutableList.of(hashBuildDriver, joinDriver);
    }