时间工具类-Java

1、根据传入时间获取该时间所在季度的第一天

/**
     * 根据传入时间获取传入日期所在季度的第一天的日期
     *
     * @param startDate
     * @return
     */
    public static String quarterStart(String startDate) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Date dBegin = null;
        try {
            dBegin = sdf.parse(startDate);
        } catch (ParseException e) {
            throw new RuntimeException(e);
        }
        Calendar calBegin = Calendar.getInstance();
        calBegin.setTime(dBegin);
        int remainder = calBegin.get(Calendar.MONTH) % 3;
        int month = remainder != 0 ? calBegin.get(Calendar.MONTH) - remainder : calBegin.get(Calendar.MONTH);

        calBegin.set(Calendar.MONTH, month);
        calBegin.set(Calendar.DAY_OF_MONTH, calBegin.getActualMinimum(Calendar.DAY_OF_MONTH));

        calBegin.setTime(calBegin.getTime());
        return sdf.format(calBegin.getTime());
    }

2、获取一段时间段内的每一天日期

/**
     * 获取时间段内的每一天[2023-08-02 ~ 2023-09-20]
     *
     * @param start
     * @param end
     * @return
     */
    public static List<String> getBetweenDate(String start, String end) {
        List<String> list = new ArrayList<>();
        LocalDate startDate = LocalDate.parse(start);
        LocalDate endDate = LocalDate.parse(end);
        long distance = ChronoUnit.DAYS.between(startDate, endDate);
        if (distance < 1) {
            return list;
        }
        Stream.iterate(startDate, d -> d.plusDays(1)).limit(distance + 1).forEach(f -> list.add(f.toString()));
        return list;
    }

3、获取一段时间段内每个月的日期

/**
     * 获取时间段内的所有月份[年月]
     *
     * @param start
     * @param end
     * @return
     */
    public static List<String> getBetweenMonth(String start, String end) {
        List<String> list = new ArrayList<>();
        LocalDate startDate = LocalDate.parse(start);
        LocalDate endDate = LocalDate.parse(end);
        long distance = ChronoUnit.MONTHS.between(startDate, endDate);
        Stream.iterate(startDate, d -> d.plusMonths(1)).limit(distance + 1).forEach(f -> {
            list.add(f.toString().substring(0, 7));
        });
        return list;
    }