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import org.apache.commons.lang3.StringUtils;import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;/*** 日期工具類** @author silence* @version 2017/12/24*/
public class DateUtil {private static final String YYYY_MM_DD = "yyyy-MM-dd";public static final SimpleDateFormat DATE_FORMAT = new SimpleDateFormat("yyyy-MM-dd");public static final SimpleDateFormat TIME_FORMAT = new SimpleDateFormat("HH:mm:ss");public static final int DAYS_OF_ONE_WEEK = 7;/*** 查當前日期是一周中的第幾天、星期幾* @return*/public static long getWhicthDay(Date today){Calendar cal = Calendar.getInstance();cal.setTime(today);// 1=Sunday,2=Monday,,,7=Saturday。return cal.get(Calendar.DAY_OF_WEEK);}/*** 判斷日期是否相等 年／月／日相等 就是相等了** @param day1* @param day2* @return*/public static boolean isDateEqualToday(Date day1, Date day2) {return day1.getYear() == day2.getYear()&& day1.getMonth() == day2.getMonth()&& day1.getDay() == day2.getDay();}/*** 計算距離baseDate 若干天的 日期* days=2 表示2天后* days=-1 一天前** @param baseDate 日期 null 表示當前日期* @param days     日期* @return*/public static Date daysBetweenWeeks(Date baseDate, int days) {Calendar c = Calendar.getInstance();if (baseDate != null)c.setTime(baseDate);c.add(Calendar.DAY_OF_MONTH, days);return c.getTime();}public static java.sql.Date fromUtilDate(Date utilDate) {java.sql.Date sqlDate = new java.sql.Date(utilDate.getTime());return sqlDate;}//    public static Date lastMonday() {
//        Date _7daysBefore = daysBetweenWeeks(null, -DAYS_OF_ONE_WEEK);
//        return mondayOfThisWeek(_7daysBefore);
//    }
//
//    public static Date lastSunday() {
//        Date _7daysBefore = daysBetweenWeeks(null, -DAYS_OF_ONE_WEEK);
//        return sundayOfThisWeek(_7daysBefore);
//    }/*** 獲取某個日期對應的 日期 的周一** @param theDate 某個日期 null的話，表示當前日期* @return Date*/public static Date mondayOfThisWeek(Date theDate) {Calendar c = Calendar.getInstance();if (theDate != null) c.setTime(theDate);c.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY); // 獲取 周一return c.getTime();}/*** 獲取某個日期對應的 日期 的周日** @param theDate 某個日期 null的話，表示當前日期*                獲取當前日期的周7,注意 日歷獲取的周期是*                周日,1,2,3,4,5,6  不是中國傳統的*                1,2,3,4,5,6,周日*                所以要加7* @return Date*/public static Date sundayOfThisWeek(Date theDate) {Calendar c = Calendar.getInstance();if (theDate != null) c.setTime(theDate);c.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);               // 獲取 周日c.add(Calendar.DAY_OF_MONTH, 7);     // 獲取 中國意義上的 周日return c.getTime();}/*** 獲取某個日期對應的 日期 的周日** @param theDate 某個日期 null的話，表示當前日期*                獲取當前日期的周7,注意 日歷獲取的周期是*                周日,1,2,3,4,5,6  不是中國傳統的*                1,2,3,4,5,6,周日*                所以要加7* @return Date*/public static Date getSundayOfThisWeek(Date theDate) {Calendar c = Calendar.getInstance();if (theDate != null) c.setTime(theDate);c.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);               // 獲取 周日c.add(Calendar.DAY_OF_MONTH, 7);     // 獲取 中國意義上的 周日if(getWhicthDay(theDate)==1){c.add(Calendar.DATE, c.getFirstDayOfWeek() - 8);}return c.getTime();}/*** 字符串轉換為日期類型** @param dateString* @return*/public static Date stringToDate(String dateString) {try {SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");return sdf.parse(dateString);} catch (ParseException e) {System.out.println(e.getMessage());}return null;}public static String dateToString(Date date) {try {SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");return sdf.format(date);} catch (Exception e) {System.out.println(e.getMessage());}return date.toString();}/*** YYYY:MM:DD hh:mm:ss --->YYYY:MM:DD** @param date* @return*/public static Date timeToDate(Date date) {SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");String s = sdf.format(date);try {return sdf.parse(s);} catch (ParseException e) {e.printStackTrace();}return null;}/*** 獲取某天當前周的周一* @param date* @return*/public static Date getThisWeekMonday(Date date) {Calendar cal = Calendar.getInstance();cal.setTime(date);// 獲得當前日期是一個星期的第幾天int dayWeek = cal.get(Calendar.DAY_OF_WEEK);if (1 == dayWeek) {cal.add(Calendar.DAY_OF_MONTH, -1);}// 設置一個星期的第一天，按中國的習慣一個星期的第一天是星期一cal.setFirstDayOfWeek(Calendar.MONDAY);// 獲得當前日期是一個星期的第幾天int day = cal.get(Calendar.DAY_OF_WEEK);// 根據日歷的規則，當前日期減去 星期幾與一個星期第一天的差值  即可計算當前周期第一天cal.add(Calendar.DATE, cal.getFirstDayOfWeek() - day);return cal.getTime();}/*** 獲取某天上周一的日期** @param date* @return*/public static Date geLastWeekMonday(Date date) {Calendar cal = Calendar.getInstance();cal.setTime(getThisWeekMonday(date));cal.add(Calendar.DATE, -7);return cal.getTime();}/*** 獲取某天下周一的日期** @param date* @return*/public static Date getNextWeekMonday(Date date) {Calendar cal = Calendar.getInstance();cal.setTime(getThisWeekMonday(date));cal.add(Calendar.DATE, 7);return cal.getTime();}/*** 獲取某天的前后幾天的日期** @param date* @param day  :正數表示后幾天,負數表示前幾天* @return*/public static Date addDay(Date date, int day) {Calendar cal = Calendar.getInstance();cal.setTime(date);cal.add(Calendar.DATE, day);return cal.getTime();}/*** 添加時間** @param date* @param time hh:mm:ss* @return*/public static Date addTime(Date date, String time) {if (StringUtils.isEmpty(time)) return date;Calendar cd = Calendar.getInstance();cd.setTime(date);String[] times = time.split(":");//eg:["01","00","00"]int[] timeUnit = {Calendar.HOUR, Calendar.MINUTE, Calendar.SECOND};if (date != null) {for (int i = 0; i < times.length; i++) {cd.add(timeUnit[i], Integer.valueOf(times[i]));}}return cd.getTime();}}

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