presto-main/src/main/java/io/prestosql/execution/scheduler/FixedSourcePartitionedScheduler.java/BucketedSplitPlacementPolicy/BucketedSplitPlacementPolicy
class BucketedSplitPlacementPolicy:        public BucketedSplitPlacementPolicy(
                NodeSelector nodeSelector,
                List<InternalNode> allNodes,
                BucketNodeMap bucketNodeMap,
                Supplier<? extends List<RemoteTask>> remoteTasks)
        {
            this.nodeSelector = requireNonNull(nodeSelector, "nodeSelector is null");
            this.allNodes = ImmutableList.copyOf(requireNonNull(allNodes, "allNodes is null"));
            this.bucketNodeMap = requireNonNull(bucketNodeMap, "bucketNodeMap is null");
            this.remoteTasks = requireNonNull(remoteTasks, "remoteTasks is null");
        }