Java 学习笔记 (三) Java 日期类型
2018-01-09 09:48 钱先生 阅读(2337) 评论(0) 编辑 收藏 举报以下内容摘自: https://www.cnblogs.com/crazylqy/p/4172324.html
import java.sql.Timestamp; import java.text.ParsePosition; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import java.util.GregorianCalendar; import java.util.regex.Pattern; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; public class DateUtils { protected static Log logger = LogFactory.getLog(DateUtils.class); // 格式:年-月-日 小时:分钟:秒 public static final String FORMAT_ONE = "yyyy-MM-dd HH:mm:ss"; // 格式:年-月-日 小时:分钟 public static final String FORMAT_TWO = "yyyy-MM-dd HH:mm"; // 格式:年月日 小时分钟秒 public static final String FORMAT_THREE = "yyyyMMdd-HHmmss"; // 格式:年-月-日 public static final String LONG_DATE_FORMAT = "yyyy-MM-dd"; // 格式:月-日 public static final String SHORT_DATE_FORMAT = "MM-dd"; // 格式:小时:分钟:秒 public static final String LONG_TIME_FORMAT = "HH:mm:ss"; //格式:年-月 public static final String MONTG_DATE_FORMAT = "yyyy-MM"; // 年的加减 public static final int SUB_YEAR = Calendar.YEAR; // 月加减 public static final int SUB_MONTH = Calendar.MONTH; // 天的加减 public static final int SUB_DAY = Calendar.DATE; // 小时的加减 public static final int SUB_HOUR = Calendar.HOUR; // 分钟的加减 public static final int SUB_MINUTE = Calendar.MINUTE; // 秒的加减 public static final int SUB_SECOND = Calendar.SECOND; static final String dayNames[] = { "星期日", "星期一", "星期二", "星期三", "星期四","星期五", "星期六" }; @SuppressWarnings("unused") private static final SimpleDateFormat timeFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); public DateUtils() {} /** * 把符合日期格式的字符串转换为日期类型 * * @param dateStr * @return */ public static java.util.Date stringtoDate(String dateStr, String format) { Date d = null; SimpleDateFormat formater = new SimpleDateFormat(format); try { formater.setLenient(false); d = formater.parse(dateStr); } catch (Exception e) { // log.error(e); d = null; } return d; } /** * 把符合日期格式的字符串转换为日期类型 */ public static java.util.Date stringtoDate(String dateStr, String format, ParsePosition pos) { Date d = null; SimpleDateFormat formater = new SimpleDateFormat(format); try { formater.setLenient(false); d = formater.parse(dateStr, pos); } catch (Exception e) { d = null; } return d; } /** * 把日期转换为字符串 * * @param date * @return */ public static String dateToString(java.util.Date date, String format) { String result = ""; SimpleDateFormat formater = new SimpleDateFormat(format); try { result = formater.format(date); } catch (Exception e) { // log.error(e); } return result; } /** * 获取当前时间的指定格式 * * @param format * @return */ public static String getCurrDate(String format) { return dateToString(new Date(), format); } /** * * @param dateStr * @param amount * @return */ public static String dateSub(int dateKind, String dateStr, int amount) { Date date = stringtoDate(dateStr, FORMAT_ONE); Calendar calendar = Calendar.getInstance(); calendar.setTime(date); calendar.add(dateKind, amount); return dateToString(calendar.getTime(), FORMAT_ONE); } /** * 两个日期相减 * * @param firstTime * @param secTime * @return 相减得到的秒数 */ public static long timeSub(String firstTime, String secTime) { long first = stringtoDate(firstTime, FORMAT_ONE).getTime(); long second = stringtoDate(secTime, FORMAT_ONE).getTime(); return (second - first) / 1000; } /** * 获得某月的天数 * * @param year * int * @param month * int * @return int */ public static int getDaysOfMonth(String year, String month) { int days = 0; if (month.equals("1") || month.equals("3") || month.equals("5") || month.equals("7") || month.equals("8") || month.equals("10") || month.equals("12")) { days = 31; } else if (month.equals("4") || month.equals("6") || month.equals("9") || month.equals("11")) { days = 30; } else { if ((Integer.parseInt(year) % 4 == 0 && Integer.parseInt(year) % 100 != 0) || Integer.parseInt(year) % 400 == 0) { days = 29; } else { days = 28; } } return days; } /** * 获取某年某月的天数 * * @param year * int * @param month * int 月份[1-12] * @return int */ public static int getDaysOfMonth(int year, int month) { Calendar calendar = Calendar.getInstance(); calendar.set(year, month - 1, 1); return calendar.getActualMaximum(Calendar.DAY_OF_MONTH); } /** * 获得当前日期 * * @return int */ public static int getToday() { Calendar calendar = Calendar.getInstance(); return calendar.get(Calendar.DATE); } /** * 获得当前月份 * * @return int */ public static int getToMonth() { Calendar calendar = Calendar.getInstance(); return calendar.get(Calendar.MONTH) + 1; } /** * 获得当前年份 * * @return int */ public static int getToYear() { Calendar calendar = Calendar.getInstance(); return calendar.get(Calendar.YEAR); } /** * 返回日期的天 * * @param date * Date * @return int */ public static int getDay(Date date) { Calendar calendar = Calendar.getInstance(); calendar.setTime(date); return calendar.get(Calendar.DATE); } /** * 返回日期的年 * * @param date * Date * @return int */ public static int getYear(Date date) { Calendar calendar = Calendar.getInstance(); calendar.setTime(date); return calendar.get(Calendar.YEAR); } /** * 返回日期的月份,1-12 * * @param date * Date * @return int */ public static int getMonth(Date date) { Calendar calendar = Calendar.getInstance(); calendar.setTime(date); return calendar.get(Calendar.MONTH) + 1; } /** * 计算两个日期相差的天数,如果date2 > date1 返回正数,否则返回负数 * * @param date1 * Date * @param date2 * Date * @return long */ public static long dayDiff(Date date1, Date date2) { return (date2.getTime() - date1.getTime()) / 86400000; } /** * 比较两个日期的年差 * * @param befor * @param after * @return */ public static int yearDiff(String before, String after) { Date beforeDay = stringtoDate(before, LONG_DATE_FORMAT); Date afterDay = stringtoDate(after, LONG_DATE_FORMAT); return getYear(afterDay) - getYear(beforeDay); } /** * 比较指定日期与当前日期的差 * * @param befor * @param after * @return */ public static int yearDiffCurr(String after) { Date beforeDay = new Date(); Date afterDay = stringtoDate(after, LONG_DATE_FORMAT); return getYear(beforeDay) - getYear(afterDay); } /** * 比较指定日期与当前日期的差 * @param before * @return */ public static long dayDiffCurr(String before) { Date currDate = DateUtils.stringtoDate(currDay(), LONG_DATE_FORMAT); Date beforeDate = stringtoDate(before, LONG_DATE_FORMAT); return (currDate.getTime() - beforeDate.getTime()) / 86400000; } /** * 获取每月的第一周 * @param year * @param month * @return */ public static int getFirstWeekdayOfMonth(int year, int month) { Calendar c = Calendar.getInstance(); c.setFirstDayOfWeek(Calendar.SATURDAY); // 星期天为第一天 c.set(year, month - 1, 1); return c.get(Calendar.DAY_OF_WEEK); } /** * 获取每月的最后一周 * @param year * @param month * @return */ public static int getLastWeekdayOfMonth(int year, int month) { Calendar c = Calendar.getInstance(); c.setFirstDayOfWeek(Calendar.SATURDAY); // 星期天为第一天 c.set(year, month - 1, getDaysOfMonth(year, month)); return c.get(Calendar.DAY_OF_WEEK); } /** * 获得当前日期字符串,格式"yyyy-MM-dd HH:mm:ss" * * @return */ public static String getNow() { Calendar today = Calendar.getInstance(); return dateToString(today.getTime(), FORMAT_ONE); } /** * 根据生日获取星座 * * @param birth * YYYY-mm-dd * @return */ public static String getAstro(String birth) { if (!isDate(birth)) { birth = "2000" + birth; } if (!isDate(birth)) { return ""; } int month = Integer.parseInt(birth.substring(birth.indexOf("-") + 1, birth.lastIndexOf("-"))); int day = Integer.parseInt(birth.substring(birth.lastIndexOf("-") + 1)); String s = "魔羯水瓶双鱼牡羊金牛双子巨蟹狮子处女天秤天蝎射手魔羯"; int[] arr = { 20, 19, 21, 21, 21, 22, 23, 23, 23, 23, 22, 22 }; int start = month * 2 - (day < arr[month - 1] ? 2 : 0); return s.substring(start, start + 2) + "座"; } /** * 判断日期是否有效,包括闰年的情况 * * @param date * YYYY-mm-dd * @return */ public static boolean isDate(String date) { StringBuffer reg = new StringBuffer("^((\\d{2}(([02468][048])|([13579][26]))-?((((0?"); reg.append("[13578])|(1[02]))-?((0?[1-9])|([1-2][0-9])|(3[01])))"); reg.append("|(((0?[469])|(11))-?((0?[1-9])|([1-2][0-9])|(30)))|"); reg.append("(0?2-?((0?[1-9])|([1-2][0-9])))))|(\\d{2}(([02468][12"); reg.append("35679])|([13579][01345789]))-?((((0?[13578])|(1[02]))"); reg.append("-?((0?[1-9])|([1-2][0-9])|(3[01])))|(((0?[469])|(11))"); reg.append("-?((0?[1-9])|([1-2][0-9])|(30)))|(0?2-?((0?["); reg.append("1-9])|(1[0-9])|(2[0-8]))))))"); Pattern p = Pattern.compile(reg.toString()); return p.matcher(date).matches(); } /** * 取得指定日期过 months 月后的日期 (当 months 为负数表示指定月之前); * * @param date * 日期 为null时表示当天 * @param month * 相加(相减)的月数 */ public static Date nextMonth(Date date, int months) { Calendar cal = Calendar.getInstance(); if (date != null) { cal.setTime(date); } cal.add(Calendar.MONTH, months); return cal.getTime(); } /** * 取得指定日期过 day 天后的日期 (当 day 为负数表示指日期之前); * * @param date * 日期 为null时表示当天 * @param month * 相加(相减)的月数 */ public static Date nextDay(Date date, int day) { Calendar cal = Calendar.getInstance(); if (date != null) { cal.setTime(date); } cal.add(Calendar.DAY_OF_YEAR, day); return cal.getTime(); } /** * 取得距离今天 day 日的日期 * @param day * @param format * @return * @author chenyz */ public static String nextDay(int day, String format) { Calendar cal = Calendar.getInstance(); cal.setTime(new Date()); cal.add(Calendar.DAY_OF_YEAR, day); return dateToString(cal.getTime(), format); } /** * 取得指定日期过 day 周后的日期 (当 day 为负数表示指定月之前) * * @param date * 日期 为null时表示当天 */ public static Date nextWeek(Date date, int week) { Calendar cal = Calendar.getInstance(); if (date != null) { cal.setTime(date); } cal.add(Calendar.WEEK_OF_MONTH, week); return cal.getTime(); } /** * 获取当前的日期(yyyy-MM-dd) */ public static String currDay() { return DateUtils.dateToString(new Date(), DateUtils.LONG_DATE_FORMAT); } /** * 获取昨天的日期 * * @return */ public static String befoDay() { return befoDay(DateUtils.LONG_DATE_FORMAT); } /** * 根据时间类型获取昨天的日期 * @param format * @return * @author chenyz */ public static String befoDay(String format) { return DateUtils.dateToString(DateUtils.nextDay(new Date(), -1), format); } /** * 获取明天的日期 */ public static String afterDay() { return DateUtils.dateToString(DateUtils.nextDay(new Date(), 1), DateUtils.LONG_DATE_FORMAT); } /** * 取得当前时间距离1900/1/1的天数 * * @return */ public static int getDayNum() { int daynum = 0; GregorianCalendar gd = new GregorianCalendar(); Date dt = gd.getTime(); GregorianCalendar gd1 = new GregorianCalendar(1900, 1, 1); Date dt1 = gd1.getTime(); daynum = (int) ((dt.getTime() - dt1.getTime()) / (24 * 60 * 60 * 1000)); return daynum; } /** * getDayNum的逆方法(用于处理Excel取出的日期格式数据等) * * @param day * @return */ public static Date getDateByNum(int day) { GregorianCalendar gd = new GregorianCalendar(1900, 1, 1); Date date = gd.getTime(); date = nextDay(date, day); return date; } /** 针对yyyy-MM-dd HH:mm:ss格式,显示yyyymmdd */ public static String getYmdDateCN(String datestr) { if (datestr == null) return ""; if (datestr.length() < 10) return ""; StringBuffer buf = new StringBuffer(); buf.append(datestr.substring(0, 4)).append(datestr.substring(5, 7)) .append(datestr.substring(8, 10)); return buf.toString(); } /** * 获取本月第一天 * * @param format * @return */ public static String getFirstDayOfMonth(String format) { Calendar cal = Calendar.getInstance(); cal.set(Calendar.DATE, 1); return dateToString(cal.getTime(), format); } /** * 获取本月最后一天 * * @param format * @return */ public static String getLastDayOfMonth(String format) { Calendar cal = Calendar.getInstance(); cal.set(Calendar.DATE, 1); cal.add(Calendar.MONTH, 1); cal.add(Calendar.DATE, -1); return dateToString(cal.getTime(), format); } /** * @desc: 获取系统 Timestamp,如(2014-12-18 17:35:46.651) * @return Timestamp */ public static Timestamp getCurrentSysTimestamp(){ Timestamp d = new Timestamp(System.currentTimeMillis()); return d; } //----------------------------------------以下是(Long和Date)(Long和yyyy-MM-dd)转换--------------------------------------------------- /** * 获取当前时间的秒数 1970/01/01至今的秒数,,等于new Date().getTime()/1000 * @param date * @return * @throws Exception */ public static long getNowTimeStamp() { long stamp = 0L; Date date1 = new Date(); Date date2 = null; try { date2 = (new SimpleDateFormat("yyyy/MM/dd HH:mm:ss")).parse("1970/01/01 08:00:00"); } catch (Exception e) { e.printStackTrace(); } stamp = (date1.getTime() - date2.getTime()) / 1000L; return stamp; } /** * 获取当前时间的毫秒数 1970/01/01至今的毫秒数,等于new Date().getTime() * @param date * @return * @throws Exception */ public static long getNowTimeStampMs(){ long stamp = 0L; Date date1 = new Date(); Date date2 = null; try { date2 = (new SimpleDateFormat("yyyy/MM/dd HH:mm:ss")).parse("1970/01/01 08:00:00"); } catch (Exception e) { e.printStackTrace(); } stamp = (date1.getTime() - date2.getTime()); return stamp; } /** * 时间转换成秒 1970/01/01至今的秒数(Date转long),等于new Date().getTime()/1000 * @param date * @return * @throws Exception */ public static long getTimeStampByDate(Date date) { long stamp = 0L; Date date1 = date; Date date2 = null; try { date2 = (new SimpleDateFormat("yyyy/MM/dd HH:mm:ss")).parse("1970/01/01 08:00:00"); stamp = (date1.getTime() - date2.getTime()) / 1000L; } catch (Exception e) { stamp = 0L; } return stamp; } /** * 时间转换成秒 1970/01/01至今的豪秒数(Date转long) * @param date * @return * @throws Exception */ public static long getTimeStampMsByDate(Date date) { long stamp = 0L; Date date1 = date; Date date2 = null; try { date2 = (new SimpleDateFormat("yyyy/MM/dd HH:mm:ss")).parse("1970/01/01 08:00:00"); stamp = (date1.getTime() - date2.getTime()); } catch (Exception e) { stamp = 0L; } return stamp; } /** * 将时间由秒转换成指定格式,如(long转:yyyy-MM-dd HH:mm:ss) * @param second * @param format * @return * @throws Exception */ public static String getYYYYByTimeStamp(Long second, String format) { if(second==null||second==0){ return ""; } Date da = null; try { da = (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")).parse("1970-01-01 08:00:00"); } catch (Exception e) { e.printStackTrace(); } Date date = new Date(da.getTime() + second * 1000L); return (new SimpleDateFormat(format)).format(date); } /** * 将时间由毫秒转换成指定格式,如(long转:yyyy-MM-dd HH:mm:ss) * @param second * @param format * @return * @throws Exception */ public static String getYYYYbyTimeStampMs(Long second, String format) { if(second==null||second==0){ return ""; } Date da = null; try { da = (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")).parse("1970-01-01 08:00:00"); } catch (Exception e) { e.printStackTrace(); } Date date = new Date(da.getTime() + second ); return (new SimpleDateFormat(format)).format(date); } /** * 1970/01/01至今的秒数转换成Date * @param TimeStamp * @return */ public static Date getDateByTimeStamp(Long TimeStamp){ return new Date(TimeStamp*1000); } /** * 1970/01/01至今的豪秒数转换成Date * @param TimeStampMs * @return */ public static Date getDateByTimeStampMs(Long TimeStampMs){ return new Date(TimeStampMs); } }