Java获取本周、本月、本年、及各种时间段的工具类

import java.sql.Timestamp;import java.util.ArrayList;import java.util.Calendar;import java.util.Date;import java.util.GregorianCalendar;import java.util.List;public class DateUtils {    // 获取当天的开始时间    public static java.util.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 java.util.Date getDayEnd() {    Calendar cal = new GregorianCalendar();    cal.set(Calendar.HOUR_OF_DAY, 23);    cal.set(Calendar.MINUTE, 59);    cal.set(Calendar.SECOND, 59);    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();    }    // 获取明天的开始时间    public static Date getBeginDayOfTomorrow() {    Calendar cal = new GregorianCalendar();    cal.setTime(getDayBegin());    cal.add(Calendar.DAY_OF_MONTH, 1);    return cal.getTime();    }    // 获取明天的结束时间    public static Date getEndDayOfTomorrow() {    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());    }    // 获取上个月的开始时间    public static Date getBeginDayOfLastMonth() {    Date date = new Date();    Calendar calendar = Calendar.getInstance();    calendar.setTime(date);    calendar.add(calendar.MONTH, -1);    calendar.set(calendar.DAY_OF_MONTH, 1);    return getDayStartTime(calendar.getTime());    }    // 获取上个月的结束时间    public static Date getEndDayOfLastMonth() {    Date date = new Date();    Calendar calendar = Calendar.getInstance();    calendar.setTime(date);    calendar.add(calendar.MONTH, -1);    int day = calendar.getActualMaximum(5);    calendar.set(calendar.DAY_OF_MONTH, day);    return getDayEndTime(calendar.getTime());    }    // 获取本年的开始时间    public static java.util.Date getBeginDayOfYear() {    Calendar cal = Calendar.getInstance();    cal.set(Calendar.YEAR, getNowYear());    // cal.set    cal.set(Calendar.MONTH, Calendar.JANUARY);    cal.set(Calendar.DATE, 1);    return getDayStartTime(cal.getTime());    }    // 获取本年的结束时间    public static java.util.Date getEndDayOfYear() {    Calendar cal = Calendar.getInstance();    cal.set(Calendar.YEAR, getNowYear());    cal.set(Calendar.MONTH, Calendar.DECEMBER);    cal.set(Calendar.DATE, 31);    return getDayEndTime(cal.getTime());    }    // 获取某个日期的开始时间    public static Timestamp getDayStartTime(Date d) {    Calendar calendar = Calendar.getInstance();    if (null != d)        calendar.setTime(d);    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 d) {    Calendar calendar = Calendar.getInstance();    if (null != d)        calendar.setTime(d);    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;    }    // 获取两个日期中的最大日期    public static Date max(Date beginDate, Date endDate) {    if (beginDate == null) {        return endDate;    }    if (endDate == null) {        return beginDate;    }    if (beginDate.after(endDate)) {        return beginDate;    }    return endDate;    }    // 获取两个日期中的最小日期    public static Date min(Date beginDate, Date endDate) {    if (beginDate == null) {        return endDate;    }    if (endDate == null) {        return beginDate;    }    if (beginDate.after(endDate)) {        return endDate;    }    return beginDate;    }    // 返回某月该季度的第一个月    public static Date getFirstSeasonDate(Date date) {    final int[] SEASON = { 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4 };    Calendar cal = Calendar.getInstance();    cal.setTime(date);    int sean = SEASON[cal.get(Calendar.MONTH)];    cal.set(Calendar.MONTH, sean * 3 - 3);    return cal.getTime();    }    // 返回某个日期下几天的日期    public static Date getNextDay(Date date, int i) {    Calendar cal = new GregorianCalendar();    cal.setTime(date);    cal.set(Calendar.DATE, cal.get(Calendar.DATE) + i);    return cal.getTime();    }    // 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();    }    // 获取某年某月到某年某月按天的切片日期集合（间隔天数的日期集合）    public static List getTimeList(int beginYear, int beginMonth, int endYear, int endMonth, int k) {    List list = new ArrayList();    if (beginYear == endYear) {        for (int j = beginMonth; j <= endMonth; j++) {        list.add(getTimeList(beginYear, j, k));        }    } else {        {        for (int j = beginMonth; j < 12; j++) {            list.add(getTimeList(beginYear, j, k));        }        for (int i = beginYear + 1; i < endYear; i++) {            for (int j = 0; j < 12; j++) {            list.add(getTimeList(i, j, k));            }        }        for (int j = 0; j <= endMonth; j++) {            list.add(getTimeList(endYear, j, k));        }        }    }    return list;    }    // 获取某年某月按天切片日期集合（某个月间隔多少天的日期集合）    public static List getTimeList(int beginYear, int beginMonth, int k) {    List list = new ArrayList();    Calendar begincal = new GregorianCalendar(beginYear, beginMonth, 1);    int max = begincal.getActualMaximum(Calendar.DATE);    for (int i = 1; i < max; i = i + k) {        list.add(begincal.getTime());        begincal.add(Calendar.DATE, k);    }    begincal = new GregorianCalendar(beginYear, beginMonth, max);    list.add(begincal.getTime());    return list;    }    // 获取某年某月的第一天日期    public static Date getStartMonthDate(int year, int month) {    Calendar calendar = Calendar.getInstance();    calendar.set(year, month - 1, 1);    return calendar.getTime();    }    // 获取某年某月的最后一天日期    public static Date getEndMonthDate(int year, int month) {    Calendar calendar = Calendar.getInstance();    calendar.set(year, month - 1, 1);    int day = calendar.getActualMaximum(5);    calendar.set(year, month - 1, day);    return calendar.getTime();    }}