常用时间工具类

public class DateUtils {
    private static final Logger logger = LoggerFactory.getLogger(DateUtils.class);

    // 将 Date 类型的时间格式化为 String 类型 (例如:将 Fri Dec 31 14:17:04 CST 2021 转化为 2021-12-31 14:17:04)
    public static String formatDateToString(Date date, String format) {
        try {
            if (Objects.nonNull(date)) {
                SimpleDateFormat sdf = new SimpleDateFormat(format);
                return sdf.format(date);
            }
        } catch (Exception e) {
            logger.error("formatDate error, the reason is : {}", e);
        }
        return "";
    }

    // 将 String 类型的时间解析为 Date 类型 (例如:将 2021-12-31 15:18:07 转化为 Fri Dec 31 15:18:07 CST 2021)
    public static Date parseDateToString(String dateStr, String format) {
        try {
            if (StringUtils.isNotBlank(dateStr)) {
                SimpleDateFormat sdf = new SimpleDateFormat(format);
                return sdf.parse(dateStr);
            }
        } catch (ParseException e) {
            logger.error("parseDateFromString error, the reason is : {}", e);
        }
        return null;
    }

    // 将 Date 类型的时间格式化为 String 类型,附带毫秒值 (例如:将 Fri Dec 31 15:25:41 CST 2021 转化为 2021-12-31 15:25:41.669)
    public static String formatDateToStringWithMills(Date date) {
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.S");
        String dateStr = simpleDateFormat.format(date);
        return dateStr;
    }

    // 将一种格式的字符串时间转化为另外一种格式的字符串时间 (例如:将 yyyy-MM-dd HH:mm:ss 格式的时间转化为 yyyy-MM-dd)
    public static String getDateStr(String dateStr, String format1, String format2) throws ParseException {
        SimpleDateFormat sdf1 = new SimpleDateFormat(format1);
        Date date = sdf1.parse(dateStr);

        SimpleDateFormat sdf2 = new SimpleDateFormat(format2);
        return sdf2.format(date);
    }

    // 将 yyyy-MM-dd HH：mm：ss 格式的时间转化为秒级时间戳 (例如:将 2021-12-31 15:57:53 转化为 1640937473)
    public static Long getTimestampFromDateStr(String dateStr) {
        return Timestamp.valueOf(dateStr).getTime() / 1000;
    }

    // 将秒级时间戳转化为 yyyy-MM-dd HH:mm:ss 格式时间 (例如:将 2021-12-31 15:57:53 转化为 1640937473)
    public static String getDateStrFromSecondTimestamp(Long secondTimestamp) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = new Date(secondTimestamp * 1000);
        return sdf.format(date);
    }

    // 通过两个时间字符串比较时间的先后
    public static int compare_date(String dateStr1, String dateStr2, String format) {
        DateFormat df = new SimpleDateFormat(format);
        try {
            Date date1 = df.parse(dateStr1);
            Date date2 = df.parse(dateStr2);
            if (date1.getTime() > date2.getTime()) {
                System.out.println("dateStr1 在 dateStr2 后");
                return 1;
            } else if (date1.getTime() < date2.getTime()) {
                System.out.println("dateStr1 在 dateStr2 前");
                return -1;
            } else {
                System.out.println("时间相等");
                return 0;
            }
        } catch (Exception exception) {
            exception.printStackTrace();
        }
        return 0;
    }

    // 获取传入时间的当天开始时间(例如传入 2019-08-29 12:23:23 返回 2019-08-29 00:00:00)
    public static String getDateStrBegin(Date date) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        calendar.set(Calendar.HOUR_OF_DAY, 0);
        calendar.set(Calendar.MINUTE, 0);
        calendar.set(Calendar.SECOND, 0);

        return sdf.format(calendar.getTime());
    }

    // 获取传入时间的当天结束时间 (例如传入 2019-08-29 12:23:23 返回 2019-08-29 23:59:59)
    public static String getDateStrEnd(Date date) {
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        calendar.set(Calendar.HOUR_OF_DAY, 23);
        calendar.set(Calendar.MINUTE, 59);
        calendar.set(Calendar.SECOND, 59);

        return simpleDateFormat.format(calendar.getTime());
    }

    // 获取指定时间与当前时间的差值,单位 s (例如:指定时间为 2021-12-31 16:01:00 当前时间为 2021-12-31 16:00:00,那么他们的差值为 60 s)
    public static Long getMiol() {
        Calendar ca = Calendar.getInstance();
        // 指定时间(毫秒)
        ca.set(Calendar.HOUR_OF_DAY, 16);
        ca.set(Calendar.MINUTE, 0);
        ca.set(Calendar.SECOND, 0);
        long assignTime = ca.getTimeInMillis() / 1000;

        // 当前时间(毫秒)
        long currentTime = (System.currentTimeMillis()) / 1000;
        long different = assignTime - currentTime;

        return different;
    }

    // 获取当天的开始时间
    public static Date getDayBegin() {
        Calendar cal = new GregorianCalendar();
        cal.set(Calendar.HOUR_OF_DAY, 0);
        cal.set(Calendar.MINUTE, 0);
        cal.set(Calendar.SECOND, 0);
        cal.set(Calendar.MILLISECOND, 0);
        return cal.getTime();
    }

    // 获取当天的结束时间
    public static Date getDayEnd() {
        Calendar cal = new GregorianCalendar();
        cal.set(Calendar.HOUR_OF_DAY, 23);
        cal.set(Calendar.MINUTE, 59);
        cal.set(Calendar.SECOND, 59);
        cal.set(Calendar.MILLISECOND, 999);
        return cal.getTime();
    }

    // 获取昨天的开始时间
    public static Date getBeginDayOfYesterday() {
        Calendar cal = new GregorianCalendar();
        cal.setTime(getDayBegin());
        cal.add(Calendar.DAY_OF_MONTH, -1);
        return cal.getTime();
    }

    // 获取昨天的结束时间
    public static Date getEndDayOfYesterDay() {
        Calendar cal = new GregorianCalendar();
        cal.setTime(getDayEnd());
        cal.add(Calendar.DAY_OF_MONTH, -1);
        return cal.getTime();
    }

    // 获取本周的开始时间
    public static Date getBeginDayOfWeek() {
        Date date = new Date();
        if (date == null) {
            return null;
        }
        Calendar cal = Calendar.getInstance();
        cal.setTime(date);
        int dayofweek = cal.get(Calendar.DAY_OF_WEEK);
        if (dayofweek == 1) {
            dayofweek += 7;
        }
        cal.add(Calendar.DATE, 2 - dayofweek);
        return getDayStartTime(cal.getTime());
    }

    // 获取本周的结束时间
    public static Date getEndDayOfWeek() {
        Calendar cal = Calendar.getInstance();
        cal.setTime(getBeginDayOfWeek());
        cal.add(Calendar.DAY_OF_WEEK, 6);
        Date weekEndSta = cal.getTime();
        return getDayEndTime(weekEndSta);
    }

    // 获取上周的开始时间
    public static Date getBeginDayOfLastWeek() {
        Date date = new Date();
        if (date == null) {
            return null;
        }
        Calendar cal = Calendar.getInstance();
        cal.setTime(date);
        int dayofweek = cal.get(Calendar.DAY_OF_WEEK);
        if (dayofweek == 1) {
            dayofweek += 7;
        }
        cal.add(Calendar.DATE, 2 - dayofweek - 7);
        return getDayStartTime(cal.getTime());
    }

    // 获取上周的结束时间
    public static Date getEndDayOfLastWeek() {
        Calendar cal = Calendar.getInstance();
        cal.setTime(getBeginDayOfLastWeek());
        cal.add(Calendar.DAY_OF_WEEK, 6);
        Date weekEndSta = cal.getTime();
        return getDayEndTime(weekEndSta);
    }

    // 获取本月的开始时间
    public static Date getBeginDayOfMonth() {
        Calendar calendar = Calendar.getInstance();
        calendar.set(getNowYear(), getNowMonth() - 1, 1);
        return getDayStartTime(calendar.getTime());
    }

    // 获取本月的结束时间
    public static Date getEndDayOfMonth() {
        Calendar calendar = Calendar.getInstance();
        calendar.set(getNowYear(), getNowMonth() - 1, 1);
        int day = calendar.getActualMaximum(5);
        calendar.set(getNowYear(), getNowMonth() - 1, day);
        return getDayEndTime(calendar.getTime());
    }

    // 获取上月的开始时间
    public static Date getBeginDayOfLastMonth() {
        Calendar calendar = Calendar.getInstance();
        calendar.set(getNowYear(), getNowMonth() - 2, 1);
        return getDayStartTime(calendar.getTime());
    }

    // 获取上月的结束时间
    public static Date getEndDayOfLastMonth() {
        Calendar calendar = Calendar.getInstance();
        calendar.set(getNowYear(), getNowMonth() - 2, 1);
        int day = calendar.getActualMaximum(5);
        calendar.set(getNowYear(), getNowMonth() - 2, day);
        return getDayEndTime(calendar.getTime());
    }

    // 获取某个日期的开始时间
    public static Timestamp getDayStartTime(Date date) {
        Calendar calendar = Calendar.getInstance();
        if (null != date)
            calendar.setTime(date);
        calendar.set(calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH), calendar.get(Calendar.DAY_OF_MONTH), 0,
                0, 0);
        calendar.set(Calendar.MILLISECOND, 0);
        return new Timestamp(calendar.getTimeInMillis());
    }

    // 获取某个日期的结束时间
    public static Timestamp getDayEndTime(Date date) {
        Calendar calendar = Calendar.getInstance();
        if (null != date)
            calendar.setTime(date);
        calendar.set(calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH), calendar.get(Calendar.DAY_OF_MONTH), 23,
                59, 59);
        calendar.set(Calendar.MILLISECOND, 999);
        return new Timestamp(calendar.getTimeInMillis());
    }

    // 获取今年是哪一年
    public static Integer getNowYear() {
        Date date = new Date();
        GregorianCalendar gc = (GregorianCalendar) Calendar.getInstance();
        gc.setTime(date);
        return Integer.valueOf(gc.get(1));
    }

    // 获取本月是哪一月
    public static int getNowMonth() {
        Date date = new Date();
        GregorianCalendar gc = (GregorianCalendar) Calendar.getInstance();
        gc.setTime(date);
        return gc.get(2) + 1;
    }

    // 两个日期相减得到的天数
    public static int getDiffDays(Date beginDate, Date endDate) {
        if (beginDate == null || endDate == null) {
            throw new IllegalArgumentException("getDiffDays param is null!");
        }
        long diff = (endDate.getTime() - beginDate.getTime()) / (1000 * 60 * 60 * 24);
        int days = new Long(diff).intValue();
        return days;
    }

    // 两个日期相减得到的毫秒数
    public static long dateDiff(Date beginDate, Date endDate) {
        long date1ms = beginDate.getTime();
        long date2ms = endDate.getTime();
        return date2ms - date1ms;
    }

    // 返回某个日期前几天的日期
    public static Date getFrontDay(Date date, int i) {
        Calendar cal = new GregorianCalendar();
        cal.setTime(date);
        cal.set(Calendar.DATE, cal.get(Calendar.DATE) - i);
        return cal.getTime();
    }

    // 获取本月的前某个月的开始时间
    public static Date getBeginDayOfBeforeMonth(int i) {
        Calendar calendar = Calendar.getInstance();
        calendar.set(getNowYear(), getNowMonth() - 1 - i, 1);
        return getDayStartTime(calendar.getTime());
    }

    // 获取本月的前某个月的结束时间
    public static Date getEndDayOfBeforeMonth(int i) {
        Calendar calendar = Calendar.getInstance();
        calendar.set(getNowYear(), getNowMonth() - 1 - i, 1);
        int day = calendar.getActualMaximum(5);
        calendar.set(getNowYear(), getNowMonth() - 1 - i, day);
        return getDayEndTime(calendar.getTime());
    }

    // 获取指定日期当月的第一天的开始时间
    public static Date getFirstDayOfGivenMonth(Date date) {
        try {
            Calendar calendar = Calendar.getInstance();
            calendar.setTime(date);
            calendar.set(Calendar.DAY_OF_MONTH, 1);
            calendar.add(Calendar.MONTH, 0);
            return getDayStartTime(calendar.getTime());
        } catch (Exception e) {
            logger.error("getFirstDayOfGivenMonth error, the reason is : {}", e);
        }
        return null;
    }
}