presto-main/src/main/java/io/prestosql/sql/planner/iterative/rule/TransformCorrelatedScalarAggregationToJoin.java/TransformCorrelatedScalarAggregationToJoin/TransformCorrelatedScalarAggregationToJoin
class TransformCorrelatedScalarAggregationToJoin:    public TransformCorrelatedScalarAggregationToJoin(Metadata metadata)
    {
        this.metadata = requireNonNull(metadata, "metadata is null");
    }