Java 驗證日期/時間的有效性

兩種方式 ：
一種是驗證時間內，一種是用正則來校驗

    /**
      * 判斷時間是否在某個時間段內
      * 
      * @param nowTime  驗證的時間
      * @param beginTime 最早時間
      * @param endTime 最晚時間
      * @return
      */
    public static boolean belongCalendar(String nowT, String beginT, String endT) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date nowTime = null;
        Date beginTime = null;
        Date endTime = null;
        try {
            nowTime = sdf.parse(nowT);
            beginTime = sdf.parse(beginT);
            endTime = sdf.parse(endT);
        } catch (ParseException e) {
        }
        Calendar date = Calendar.getInstance();
        date.setTime(nowTime);
        Calendar begin = Calendar.getInstance();
        begin.setTime(beginTime);
        Calendar end = Calendar.getInstance();
        end.setTime(endTime);
        if (date.after(begin) && date.before(end)) {
            return true;
        } else if (nowTime.compareTo(beginTime) == 0 || nowTime.compareTo(endTime) == 0) {
            return true;
        } else {
            return false;
        }
    }
    public static void main(String[] args) {
        System.out.println(belongCalendar("2001-05-27 00:00:00","2000-01-01 00:00:00","2021-05-27 00:00:00"));//true
        System.out.println(belongCalendar("1999-05-27 00:00:00","2000-01-01 00:00:00","2021-05-27 00:00:00"));//false
    }


    /**
     * java 正則驗證時間的有效性 年月日 時分秒
     * @param timeStr 例：2000-08-03 00:00:00
     * @return
     */
    public static  boolean valiDateTimeWithLongFormat(String timeStr) {
        String format = "((19|20)[0-9]{2})-(0?[1-9]|1[012])-(0?[1-9]|[12][0-9]|3[01]) "
                + "([01]?[0-9]|2[0-3]):[0-5]?[0-9]:[0-5]?[0-9]";
        Pattern pattern = Pattern.compile(format);
        Matcher matcher = pattern.matcher(timeStr);
        if (matcher.matches()) {
            pattern = Pattern.compile("(\\d{4})-(\\d+)-(\\d+).*");
            matcher = pattern.matcher(timeStr);
            if (matcher.matches()) {
                int y = Integer.valueOf(matcher.group(1));
                int m = Integer.valueOf(matcher.group(2));
                int d = Integer.valueOf(matcher.group(3));
                if (d > 28) {
                    Calendar c = Calendar.getInstance();
                    c.set(y, m-1, 1);
                    int lastDay = c.getActualMaximum(Calendar.DAY_OF_MONTH);
                    return (lastDay >= d);
                }
            }
            return true;
        }
        return false;
    }
    public static void main(String[] args) {
        System.out.println(valiDateTimeWithLongFormat("2001-05-27 00:00:00"));//true
        System.out.println(valiDateTimeWithLongFormat("2001-05-27"));//false
    }