presto-main/src/main/java/io/prestosql/sql/planner/optimizations/QueryCardinalityUtil.java/CardinalityExtractorPlanVisitor/CardinalityExtractorPlanVisitor
class CardinalityExtractorPlanVisitor:        public CardinalityExtractorPlanVisitor(Lookup lookup)
        {
            this.lookup = requireNonNull(lookup, "lookup is null");
        }