我们在开发中无法避免需要处理时间日期问题,这就需要积累些处理的函数了:下面是部分处理时间的函数,分享给大家:
需要注意: JDK 版本为: 1.7
public class DateUtil { private static final String yyyyMMddHHmmss = "yyyy-MM-dd HH:mm:ss"; private static final String yyyyMMdd = "yyyy-MM-dd"; private static final String HHmmdd = "HH:mm:ss"; private static final String DAY = "day", MONTH = "month", YEAR = "year", WEEK = "week"; private static final String HOUR = "hour", MINNUTE = "minute", SECOND = "second"; /** * 日期正则表达式 */ public static final String YEAR_REGEX = "^\d{4}$"; public static final String MONTH_REGEX = "^\d{4}(\-|\/|\.)\d{1,2}$"; public static final String DATE_REGEX = "^\d{4}(\-|\/|\.)\d{1,2}\1\d{1,2}$"; /** * 将日期转换为指定格式的字符串 * * @param date java.util.Date 日期(如果为NULL,则默认为当前时间) * @param format 需要转换后得到的格式(例如:"yyyy-MM-dd HH:mm:ss"){@link DateUtil#yyyyMMddHHmmss} * @return */ public static String getDateTimeStr(Date date, String format) { if (date == null) { date = new Date(); } if (format == null || format.isEmpty()) { format = yyyyMMddHHmmss; } return new SimpleDateFormat(format).format(date); } /** * 日期字符串 → 日期(java.util.Date) * * @param dateTimeStr 日期字符串(例如:"yyyy-MM-dd HH:mm:ss") * @param format 转成日期的格式(注意:必须和日期字符串中的元素对应上){@link DateUtil#yyyyMMddHHmmss} * @return */ public static Date getDateTime(String dateTimeStr, String format) { if (format == null || format.isEmpty()) { format = yyyyMMdd; } Date date = null; try { date = new SimpleDateFormat(format).parse(dateTimeStr); } catch (ParseException e) { e.printStackTrace(); } return date; } /** * 获取指定日期所在月份的天数 * * @param dateStr 格式最低要求为:"yyyy-MM-dd" * @return */ public static String getDaysOfMonth(String dateStr) { return null; } /** * 时间戳转化为北京时间日期格式 * * @param pattern 如:yyyy-MM-dd HH:mm:ss 获取时间格式为: 年-月-日 时:分:秒<br> * pattern模式匹配语法: * G 年代标志符<br> * y 年<br> * M 月<br> * d 日<br> * h 时 在上午或下午 (1~12)<br> * H 时 在一天中 (0~23)<br> * m 分<br> * s 秒<br> * S 毫秒<br> * E 星期<br> * D 一年中的第几天<br> * F 一月中第几个星期几<br> * w 一年中第几个星期<br> * W 一月中第几个星期<br> * a 上午 / 下午 标记符<br> * k 时 在一天中 (1~24)<br> * K 时 在上午或下午 (0~11)<br> * z 时区<br> * @param timestamp 时间戳 * @return */ public static String timestamp2DateTime(String pattern, long timestamp) { //使用简体中文所在的时区 SimpleDateFormat format = new SimpleDateFormat(pattern, Locale.SIMPLIFIED_CHINESE); return format.format(timestamp); } /** * 获取当前时间的时间戳,精确到秒。 * * @return 时间戳 */ public static long getTimestamp() { return System.currentTimeMillis() / 1000; } /** * 时间戳 → 指定格式的字符串 * * @param format 格式 * @param timestamp 时间戳 * @return */ public static String getDateTime(String format, long timestamp) { return new SimpleDateFormat(format).format(timestamp); } /** * 判断日期是否为月底最后一天 * * @param date 日期(java.util.Date) * @return true:是 false:否 */ public static boolean isLastDayofMonth(Date date) { Calendar calendar = Calendar.getInstance(); Calendar last = Calendar.getInstance(); calendar.setTime(date); last.set(Calendar.DAY_OF_MONTH, last.getActualMaximum(Calendar.DAY_OF_MONTH)); // 1. 此方法时间精确到秒 /*if (calendar.compareTo(last) == 0) { return true; }*/ // 2. 获取当月最大天数与当前日期比较 String start = getDateTimeStr(date, yyyyMMdd); String day = start.split("-")[2]; int days = calendar.getActualMaximum(Calendar.DAY_OF_MONTH); // 当月最大天数 if (days == Integer.parseInt(day)) { return true; } return false; } /** * 计算两时间相距多少天 * * @param startDate 开始时间(最低格式要求:"yyyy-MM-dd") * @param endDate 结束时间(最低格式要求:"yyyy-MM-dd") * @return 正数:开始时间>结束时间;<br/> 负数:开始时间 < 结束时间<br/> 0:①起止时间相同;②传入的起止时间为NULL或空字符 */ public static Integer calDateApart(String startDate, String endDate) { startDate = startDate == null || startDate.isEmpty() ? getDateTimeStr(null, yyyyMMdd) : startDate; endDate = endDate == null || endDate.isEmpty() ? getDateTimeStr(null, yyyyMMdd) : endDate; DateFormat df = new SimpleDateFormat(yyyyMMdd); Date d1 = new Date(), d2 = new Date(); try { d1 = df.parse(startDate); d2 = df.parse(endDate); } catch (ParseException e) { e.printStackTrace(); } Calendar start = Calendar.getInstance(); start.setTime(d1); Long startTime = start.getTimeInMillis(); Calendar end = Calendar.getInstance(); end.setTime(d2); Long endTime = end.getTimeInMillis(); Long oneDay = 1000 * 60 * 60 * 24l, days = (endTime - startTime) / oneDay; int day = Integer.parseInt(String.valueOf(days)); return day; } /** * 取得新的日期 * * @param date 日期 * @param days 天数 * @return 新的日期 */ public static Date addDays(Date date, long days) { Calendar cal = Calendar.getInstance(); cal.setTime(date); cal.add(Calendar.DATE, (int) days); return cal.getTime(); } /** * 比较两个时间大小(注意:两个日期中任意一个传入了NULL都会返回 0 ) * * @param date1 第一个时间 * @param date2 第二个时间 * @return -1:date1 > date2 <br/> 1:date1 < date2; <br/> 0:date1 = date2 或 两者任一个中传入了NULL */ public static int compareDay(Date date1, Date date2) { if (date1 == null || date2 == null) { return 0; } long a = date1.getTime(), b = date2.getTime(); return a < b ? 1 : (a > b ? -1 : 0); } public static boolean isBefore(Date date1, Date date2) { long a = date1.getTime(), b = date2.getTime(); if (a < b) { return true; } return false; } /** * 得到两个时间差 格式yyyy-MM-dd HH:mm:ss * * @param start 2019-06-27 14:12:40 * @param end 2019-08-27 14:12:40 * @return 5270400000 */ public static long dateSubtraction(String start, String end) { SimpleDateFormat df = new SimpleDateFormat(yyyyMMddHHmmss); try { Date date1 = df.parse(start), date2 = df.parse(end); return date2.getTime() - date1.getTime(); } catch (ParseException e) { e.printStackTrace(); return 0; } } /** * 获取当前日期是一个星期的第几天(注意:星期一为第一天,周日为最后一天) * * @param date 日期(java.util.Date) * @return 2 */ public static int getDayOfWeek(Date date) { Calendar cal = Calendar.getInstance(); cal.setTime(date); return cal.get(Calendar.DAY_OF_WEEK) - 1; } /** * 判断指定时间是否在[startTime, endTime]区间(注意:时间格式要一致) * * @param nowTime 指定时间 * @param dateSection 时间区间 2020-01-08,2020-09-09 * @return true:是,false: 否 */ public static boolean isEffectiveDate(Date nowTime, String dateSection) { try { String[] times = dateSection.split(","); Date startTime = new SimpleDateFormat(yyyyMMdd).parse(times[0]); Date endTime = new SimpleDateFormat(yyyyMMdd).parse(times[1]); if (nowTime.getTime() == startTime.getTime() || nowTime.getTime() == endTime.getTime()) { return true; } Calendar date = Calendar.getInstance(); date.setTime(nowTime); Calendar begin = Calendar.getInstance(); begin.setTime(startTime); Calendar end = Calendar.getInstance(); end.setTime(endTime); if (isSameDay(date, begin) || isSameDay(date, end)) { return true; } if (date.after(begin) && date.before(end)) { return true; } else { return false; } } catch (Exception e) { e.printStackTrace(); return false; } } public static boolean isSameDay(Calendar cal1, Calendar cal2) { if (cal1 != null && cal2 != null) { return cal1.get(0) == cal2.get(0) && cal1.get(1) == cal2.get(1) && cal1.get(6) == cal2.get(6); } else { throw new IllegalArgumentException("The date must not be null"); } } /** * 获取指定日期前后N个周期 * * @param date 指定日期 * @param period 周期(限定周期: 天"day",月"month",年"year",周"week") * @param count N (正数:前多少个周期;<br/> 负数:后多少个周期的时间) * @return 2019-08-26 */ public static String getDatePeriod(Date date, String period, int count) { Calendar calendar = Calendar.getInstance(); calendar.setTime(date); if (YEAR.equals(period)) { calendar.add(Calendar.YEAR, count); } else if (MONTH.equals(period)) { calendar.add(Calendar.MONTH, count); } else if (WEEK.equals(period)) { calendar.add(Calendar.WEEK_OF_MONTH, count); } else { calendar.add(Calendar.DAY_OF_MONTH, count); } date = calendar.getTime(); return new SimpleDateFormat(yyyyMMdd).format(date); } /** * 获取最近七天(之前的七天) * * @return 2019-08-20 */ public static String getServen() { SimpleDateFormat sdf = new SimpleDateFormat(yyyyMMdd); Calendar c = Calendar.getInstance(); c.add(Calendar.DATE, -7); Date monday = c.getTime(); String preMonday = sdf.format(monday); return preMonday; } /** * 获取最近的一个月(之前的一个月) * * @return */ public static String getPreOneMonth() { Calendar c = Calendar.getInstance(); c.add(Calendar.MONTH, -1); return new SimpleDateFormat(yyyyMMdd).format(c.getTime()); } /**** * 获取月末最后一天 * * @param sDate 2014-11-24 * @return 30或31或28或29 */ private static String getMonthMaxDay(String sDate) { Calendar cal = Calendar.getInstance(); Date date = null; try { date = new SimpleDateFormat(yyyyMMdd).parse(sDate + "-01"); } catch (ParseException e) { e.printStackTrace(); } cal.setTime(date); int last = cal.getActualMaximum(Calendar.DATE); return String.valueOf(last); } /** * 日期范围 - 切片 * <pre> * -- eg: * 年 ----------------------- sliceUpDateRange("2018", "2020"); * rs: [2018, 2019, 2020] * * 月 ----------------------- sliceUpDateRange("2018-06", "2018-08"); * rs: [2018-06, 2018-07, 2018-08] * * 日 ----------------------- sliceUpDateRange("2018-06-30", "2018-07-02"); * rs: [2018-06-30, 2018-07-01, 2018-07-02] * </pre> * * @param startDate 起始日期 * @param endDate 结束日期 * @return 切片日期 */ public static List<String> sliceUpDateRange(String startDate, String endDate) { List<String> rs = new ArrayList<>(); try { int dt = Calendar.DATE; String pattern = "yyyy-MM-dd"; if (startDate.matches(YEAR_REGEX)) { pattern = "yyyy"; dt = Calendar.YEAR; } else if (startDate.matches(MONTH_REGEX)) { pattern = "yyyy-MM"; dt = Calendar.MONTH; } else if (startDate.matches(DATE_REGEX)) { pattern = "yyyy-MM-dd"; dt = Calendar.DATE; } Calendar sc = Calendar.getInstance(), ec = Calendar.getInstance(); sc.setTime(getDateTime(startDate, pattern)); ec.setTime(getDateTime(endDate, pattern)); while (sc.compareTo(ec) < 1) { rs.add(getDateTimeStr(sc.getTime(), pattern)); sc.add(dt, 1); } } catch (Exception e) { e.printStackTrace(); } return rs; } /** * 获得本周的最后一天,周日 * * @return */ public static Date getCurrentWeekDayEndTime() { Calendar c = Calendar.getInstance(); try { int weekday = c.get(Calendar.DAY_OF_WEEK) - 1; if (weekday == 0) { weekday = 7; } c.add(Calendar.DATE, -weekday + 7); c.setTime(new SimpleDateFormat().parse(new SimpleDateFormat().format(c.getTime()) + " 23:59:59")); } catch (Exception e) { e.printStackTrace(); } return c.getTime(); } /** * 获得本周的第一天(即周一) * * @return */ public static Date getCurrentWeekDayStartTime() { Calendar c = Calendar.getInstance(); try { int weekday = c.get(Calendar.DAY_OF_WEEK) - 1; if (weekday == 0) { weekday = 7; } c.add(Calendar.DATE, -weekday + 1); c.setTime(new SimpleDateFormat().parse(new SimpleDateFormat().format(c.getTime()) + " 00:00:00")); } catch (Exception e) { e.printStackTrace(); } return c.getTime(); } /** * 获得指定日期所在日的开始时间 * * @return */ public static String getCurrentDayStartTime(Date date) { String result = (date == null) ? new SimpleDateFormat(yyyyMMdd).format(System.currentTimeMillis()) : getDateTimeStr(date, yyyyMMdd); return result.concat(" 00:00:00"); } /** * 获得指定日期所在日的结束时间 * * @return */ public static String getCurrentDayEndTime(Date date) { String result = (date == null) ? new SimpleDateFormat(yyyyMMdd).format(System.currentTimeMillis()) : getDateTimeStr(date, yyyyMMdd); return result.concat(" 23:59:59"); } /** * 根据日期范围,得到按周期划分的日期区间值 * * @param dateRange 格式最低要求有年月日,例如:"2020-01-01,2020-03-31" * @param period 周期(日"day",月"month",年"year") * @return 小区间集合 */ public static List<String> getPeriodDateList(String dateRange, String period) { String startDate = dateRange.trim().split(",")[0], endDate = dateRange.trim().split(",")[1]; Date start = getDateTime(startDate, yyyyMMdd), end = getDateTime(endDate, yyyyMMdd); List<String> result = new ArrayList<>(); if (DAY.equals(period)) { Calendar calendar = Calendar.getInstance(); calendar.setTime(start); while (start.before(end) || start.equals(end)) { result.add(new SimpleDateFormat(yyyyMMdd).format(calendar.getTimeInMillis())); // calendar.getTimeInMillis(); // String startTmp = getCurrentDayStartTime(start), endTmp = getCurrentDayEndTime(start); // result.add(startTmp.concat(",").concat(endTmp)); calendar.add(Calendar.DATE, 1); start = calendar.getTime(); } } else if (MONTH.equals(period)) { Calendar calendar = Calendar.getInstance(); calendar.setTime(start); while (start.before(end) || start.equals(end)) { result.add(new SimpleDateFormat("yyyy-MM").format(calendar.getTimeInMillis())); calendar.add(Calendar.MONTH, 1); start = calendar.getTime(); } } else if (YEAR.equals(period)) { Calendar calendar = Calendar.getInstance(); calendar.setTime(start); while (start.before(end) || start.equals(end)) { result.add(new SimpleDateFormat("yyyy").format(calendar.getTimeInMillis())); calendar.add(Calendar.YEAR, 1); start = calendar.getTime(); } } return result; } /** * 获取指定日期前后count天的集合 * * @param date 指定日期 * @param count 多少天(正数:之后;负数:之前) * @return 前/后日期的集合(包含指定日期) */ public static List<String> getDayList(Date date, int count) { List<String> result = new ArrayList<>(); Calendar c = Calendar.getInstance(); c.setTime(date); boolean flag = false; if (count < 0) { count = Math.abs(count); flag = true; } for (int i = 0; i < count; i++) { result.add(new SimpleDateFormat(yyyyMMdd).format(c.getTimeInMillis())); c.add(Calendar.DATE, flag ? -1 : 1); } if (flag){ Collections.reverse(result); } return result; } public static void main(String[] args) { // Date date = new Date(), dateDemo = getDateTime("2020-01-30 23:33:21", yyyyMMddHHmmss); // String dateStr = "2020-02-01", timeStr = "23:33:21", dateTimeStr = "2020-01-30 23:33:21"; // String dateStr2 = "2020-01-31", timeStr2 = "23:33:21", dateTimeStr2 = "2020-01-30 23:33:21"; // String dateRange = "2020-01-01,2020-02-05"; System.out.println(getDayList(new Date(), -7)); // System.out.println(getPeriodDateList(dateRange, DAY)); // System.out.println(getCurrentDayStartTime(dateDemo)); // System.out.println(getCurrentDayEndTime(dateDemo)); // System.out.println(getDateTimeStr(getCurrentWeekDayStartTime(), yyyyMMdd)); // System.out.println(getDateTimeStr(getCurrentWeekDayEndTime(), yyyyMMdd)); // System.out.println(sliceUpDateRange(dateRange.trim().split(",")[0], dateRange.trim().split(",")[1])); // System.out.println(getPeriodDateList(dateRange, DAY)); // System.out.println(getDateTimeStr(null, "hh mm ss")); // System.out.println(getDateTime(dateTimeStr, yyyyMMddHHmmss)); // System.out.println(getTimestamp()); // System.out.println(getDateTime(yyyyMMdd, System.currentTimeMillis())); // System.out.println(timestamp2DateTime(yyyyMMddHHmmss, System.currentTimeMillis())); // System.out.println(isLastDayofMonth(getDateTime(dateStr, yyyyMMdd))); // System.out.println(calDateApart(dateStr, dateStr)); // System.out.println(compareDay(getDateTime(dateStr, yyyyMMdd), getDateTime(dateStr2, yyyyMMdd))); // System.out.println(getDateTimeStr(addDays(date, 3), yyyyMMdd)); // System.out.println(dateSubtraction(dateTimeStr, dateTimeStr2)); // System.out.println(getDayOfWeek(date)); // System.out.println(isEffectiveDate(getDateTime(dateTimeStr, yyyyMMdd), dateStr.concat(",").concat(dateStr2))); // System.out.println(getDatePeriod(date, WEEK, -4)); // System.out.println(getServen()); // System.out.println(getPreOneMonth()); // System.out.println(getMonthMaxDay(dateStr)); }