core/src/main/java/com/alibaba/fastjson2/support/csv/CSVWriter.java [229:302]:
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        final long SECONDS_PER_DAY = 60 * 60 * 24;
        long epochSecond = Math.floorDiv(millis, 1000L);
        int offsetTotalSeconds;
        if (zoneId == DateUtils.SHANGHAI_ZONE_ID || zoneId.getRules() == DateUtils.SHANGHAI_ZONE_RULES) {
            offsetTotalSeconds = DateUtils.getShanghaiZoneOffsetTotalSeconds(epochSecond);
        } else {
            Instant instant = Instant.ofEpochMilli(millis);
            offsetTotalSeconds = zoneId.getRules().getOffset(instant).getTotalSeconds();
        }

        long localSecond = epochSecond + offsetTotalSeconds;
        long localEpochDay = Math.floorDiv(localSecond, SECONDS_PER_DAY);
        int secsOfDay = (int) Math.floorMod(localSecond, SECONDS_PER_DAY);
        int year, month, dayOfMonth;
        {
            final int DAYS_PER_CYCLE = 146097;
            final long DAYS_0000_TO_1970 = (DAYS_PER_CYCLE * 5L) - (30L * 365L + 7L);

            long zeroDay = localEpochDay + DAYS_0000_TO_1970;
            // find the march-based year
            zeroDay -= 60;  // adjust to 0000-03-01 so leap day is at end of four-year cycle
            long adjust = 0;
            if (zeroDay < 0) {
                // adjust negative years to positive for calculation
                long adjustCycles = (zeroDay + 1) / DAYS_PER_CYCLE - 1;
                adjust = adjustCycles * 400;
                zeroDay += -adjustCycles * DAYS_PER_CYCLE;
            }
            long yearEst = (400 * zeroDay + 591) / DAYS_PER_CYCLE;
            long doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
            if (doyEst < 0) {
                // fix estimate
                yearEst--;
                doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
            }
            yearEst += adjust;  // reset any negative year
            int marchDoy0 = (int) doyEst;

            // convert march-based values back to january-based
            int marchMonth0 = (marchDoy0 * 5 + 2) / 153;
            month = (marchMonth0 + 2) % 12 + 1;
            dayOfMonth = marchDoy0 - (marchMonth0 * 306 + 5) / 10 + 1;
            yearEst += marchMonth0 / 10;

            // check year now we are certain it is correct
            if (yearEst < Year.MIN_VALUE || yearEst > Year.MAX_VALUE) {
                throw new DateTimeException("Invalid year " + yearEst);
            }

            year = (int) yearEst;
        }

        int hour, minute, second;
        {
            final int MINUTES_PER_HOUR = 60;
            final int SECONDS_PER_MINUTE = 60;
            final int SECONDS_PER_HOUR = SECONDS_PER_MINUTE * MINUTES_PER_HOUR;

            long secondOfDay = secsOfDay;
            if (secondOfDay < 0 || secondOfDay > 86399) {
                throw new DateTimeException("Invalid secondOfDay " + secondOfDay);
            }
            int hours = (int) (secondOfDay / SECONDS_PER_HOUR);
            secondOfDay -= hours * SECONDS_PER_HOUR;
            int minutes = (int) (secondOfDay / SECONDS_PER_MINUTE);
            secondOfDay -= minutes * SECONDS_PER_MINUTE;

            hour = hours;
            minute = minutes;
            second = (int) secondOfDay;
        }

        if (year >= 0 && year <= 9999) {
            int mos = (int) Math.floorMod(millis, 1000L);
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core/src/main/java/com/alibaba/fastjson2/writer/ObjectWriterImplDate.java [114:188]:
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            final long SECONDS_PER_DAY = 60 * 60 * 24;

            long epochSecond = Math.floorDiv(millis, 1000L);
            int offsetTotalSeconds;
            if (zoneId == DateUtils.SHANGHAI_ZONE_ID || zoneId.getRules() == DateUtils.SHANGHAI_ZONE_RULES) {
                offsetTotalSeconds = DateUtils.getShanghaiZoneOffsetTotalSeconds(epochSecond);
            } else {
                Instant instant = Instant.ofEpochMilli(millis);
                offsetTotalSeconds = zoneId.getRules().getOffset(instant).getTotalSeconds();
            }

            long localSecond = epochSecond + offsetTotalSeconds;
            long localEpochDay = Math.floorDiv(localSecond, SECONDS_PER_DAY);
            int secsOfDay = (int) Math.floorMod(localSecond, SECONDS_PER_DAY);
            int year, month, dayOfMonth;
            {
                final int DAYS_PER_CYCLE = 146097;
                final long DAYS_0000_TO_1970 = (DAYS_PER_CYCLE * 5L) - (30L * 365L + 7L);

                long zeroDay = localEpochDay + DAYS_0000_TO_1970;
                // find the march-based year
                zeroDay -= 60;  // adjust to 0000-03-01 so leap day is at end of four year cycle
                long adjust = 0;
                if (zeroDay < 0) {
                    // adjust negative years to positive for calculation
                    long adjustCycles = (zeroDay + 1) / DAYS_PER_CYCLE - 1;
                    adjust = adjustCycles * 400;
                    zeroDay += -adjustCycles * DAYS_PER_CYCLE;
                }
                long yearEst = (400 * zeroDay + 591) / DAYS_PER_CYCLE;
                long doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
                if (doyEst < 0) {
                    // fix estimate
                    yearEst--;
                    doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
                }
                yearEst += adjust;  // reset any negative year
                int marchDoy0 = (int) doyEst;

                // convert march-based values back to january-based
                int marchMonth0 = (marchDoy0 * 5 + 2) / 153;
                month = (marchMonth0 + 2) % 12 + 1;
                dayOfMonth = marchDoy0 - (marchMonth0 * 306 + 5) / 10 + 1;
                yearEst += marchMonth0 / 10;

                // check year now we are certain it is correct
                if (yearEst < Year.MIN_VALUE || yearEst > Year.MAX_VALUE) {
                    throw new DateTimeException("Invalid year " + yearEst);
                }

                year = (int) yearEst;
            }

            int hour, minute, second;
            {
                final int MINUTES_PER_HOUR = 60;
                final int SECONDS_PER_MINUTE = 60;
                final int SECONDS_PER_HOUR = SECONDS_PER_MINUTE * MINUTES_PER_HOUR;

                long secondOfDay = secsOfDay;
                if (secondOfDay < 0 || secondOfDay > 86399) {
                    throw new DateTimeException("Invalid secondOfDay " + secondOfDay);
                }
                int hours = (int) (secondOfDay / SECONDS_PER_HOUR);
                secondOfDay -= hours * SECONDS_PER_HOUR;
                int minutes = (int) (secondOfDay / SECONDS_PER_MINUTE);
                secondOfDay -= minutes * SECONDS_PER_MINUTE;

                hour = hours;
                minute = minutes;
                second = (int) secondOfDay;
            }

            if (year >= 0 && year <= 9999) {
                int mos = (int) Math.floorMod(millis, 1000L);
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