presto-main/src/main/java/io/prestosql/execution/NodeTaskMap.java/TaskPartitionedSplitCountTracker/toString
class TaskPartitionedSplitCountTracker:            @Override
            public String toString()
            {
                return toStringHelper(this)
                        .add("taskId", taskId)
                        .add("splits", localPartitionedSplitCount)
                        .toString();
            }