获取某一个年份的12个月始末日期

    //月份始末key
    private static final String BM = "beginOfMonth";
    private static final String EM = "endOfMonth";

/**
     * 获取十二个月份的统计时间区间.
     *
     * @param statistTime 统计时间  2021
     * @return list
     */
    private List<Map<String, String>> getMonthDate(String statistTime) {
        List<Map<String, String>> resList = new ArrayList<>();
        try {
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM");
            Calendar c = Calendar.getInstance();
            int year = Integer.parseInt(statistTime);
            Date startDate = sdf.parse(year + "-01");
            Date endDate = sdf.parse(year + "-12");
            c.setTime(startDate);
            while (c.getTime().compareTo(endDate) <= 0) {
                String time = sdf.format(c.getTime());
                c.add(Calendar.MONTH, 1);
                String beginOfMonth = DateUtil.format(DateUtil.beginOfMonth(sdf.parse(time)).toJdkDate(), "yyyy-MM-dd HH:mm:ss");
                String endOfMonth = DateUtil.format(DateUtil.endOfMonth(sdf.parse(time)).toJdkDate(), "yyyy-MM-dd HH:mm:ss");
                Map<String, String> resMap = new LinkedHashMap<>();
                resMap.put(BM, beginOfMonth);
                resMap.put(EM, endOfMonth);
                resList.add(resMap);
            }
        } catch (ParseException e) {
            LOGGER.error("日期转化异常:", e);
        }
        return resList;
    }