presto-main/src/main/java/io/prestosql/operator/WindowOperator.java/SpillablePagesToPagesIndexes/SpillablePagesToPagesIndexes
class SpillablePagesToPagesIndexes:        SpillablePagesToPagesIndexes(
                PagesIndexWithHashStrategies inMemoryPagesIndexWithHashStrategies,
                PagesIndexWithHashStrategies mergedPagesIndexWithHashStrategies,
                List<Type> sourceTypes,
                List<Integer> orderChannels,
                List<SortOrder> ordering,
                SpillerFactory spillerFactory,
                PageWithPositionComparator pageWithPositionComparator)
        {
            this.inMemoryPagesIndexWithHashStrategies = inMemoryPagesIndexWithHashStrategies;
            this.mergedPagesIndexWithHashStrategies = mergedPagesIndexWithHashStrategies;
            this.sourceTypes = sourceTypes;
            this.orderChannels = orderChannels;
            this.ordering = ordering;
            this.localUserMemoryContext = operatorContext.aggregateUserMemoryContext().newLocalMemoryContext(SpillablePagesToPagesIndexes.class.getSimpleName());
            this.localRevocableMemoryContext = operatorContext.aggregateRevocableMemoryContext().newLocalMemoryContext(SpillablePagesToPagesIndexes.class.getSimpleName());
            this.spillerFactory = spillerFactory;
            this.pageWithPositionComparator = pageWithPositionComparator;

            this.currentSpillGroupRowPage = Optional.empty();
            this.spiller = Optional.empty();
        }