presto-main/src/main/java/io/prestosql/operator/index/IndexSourceOperator.java/IndexSourceOperator/IndexSourceOperator
class IndexSourceOperator:    public IndexSourceOperator(
            OperatorContext operatorContext,
            PlanNodeId planNodeId,
            ConnectorIndex index,
            Function<RecordSet, RecordSet> probeKeyNormalizer)
    {
        this.operatorContext = requireNonNull(operatorContext, "operatorContext is null");
        this.planNodeId = requireNonNull(planNodeId, "planNodeId is null");
        this.index = requireNonNull(index, "index is null");
        this.probeKeyNormalizer = requireNonNull(probeKeyNormalizer, "probeKeyNormalizer is null");
    }