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 List<StockDayK> dayKLineList = getIndexDayKList(code, endDate, (count) * 5 + 1);
        Map<LocalDate, List<StockDayK>> weekMap = dayKLineList.parallelStream()
                .collect(Collectors.groupingBy(
                        ((Function<StockDayK, LocalDate>) StockDayK::getDate)
                                .andThen(dates -> dates
                                        .with(TemporalAdjusters.previous(DayOfWeek.SUNDAY)))
                ));
        Map<LocalDate, List<StockDayK>> monthMap = dayKLineList.parallelStream()
                .collect(Collectors.groupingBy(
                        ((Function<StockDayK, LocalDate>) StockDayK::getDate)
                                .andThen(s -> LocalDate.of(s.getYear(), s.getMonthValue(), 1))
                ));
                
                
                
 List<WeekEntity> klist = collect2.get(Signal.K).stream()
                .collect(Collectors.toMap(WeekEntity::getCode, Function.identity(), (a, b) -> a.getChange() < b.getChange() ? a : b, HashMap::new))
                .values()
                .stream()
                .sorted(Comparator.comparing(WeekEntity::getChange))
                .limit(limit)
                .collect(Collectors.toList());
                


 Map<String, Map<IndexType, List<StockOptimizedIndex>>> collect = preDayList.stream()
            .collect(Collectors.groupingBy(StockOptimizedIndex::getCode,
                Collectors.groupingBy(StockOptimizedIndex::getType,
                    Collectors.collectingAndThen(Collectors.toList(), lists ->
                        lists.stream().sorted(Comparator.comparing(StockOptimizedIndex::getDate).reversed()).limit(2)
                            .collect(Collectors.toList())))));