超详细的Java时间工具类

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package com.td.util;
 
import java.sql.Timestamp;
import java.text.ParseException;
import java.text.ParsePosition;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.List;
import java.util.Locale;
import java.util.Random;
 
import org.apache.log4j.chainsaw.Main;
 
/**
 * 超详细的时间工具类
 * @author Administrator
 *
 */
public class TimeUtil {
     
    //============================借助Calendar类获取今天、昨天、本周、上周、本年及特定时间的开始时间和结束时间（返回类型为date类型）========================
     
    /**
     * 获取当天开始时间
     * @return
     */
    public static Date getDayBegin(){
        Calendar cal=Calendar.getInstance();
        cal.set(Calendar.HOUR_OF_DAY, 0);//0点
        cal.set(Calendar.MINUTE, 0);//0分
        cal.set(Calendar.SECOND, 0);//0秒
        cal.set(Calendar.MILLISECOND, 0);//0毫秒
        return cal.getTime();
    }
     
     
    /**
     * 获取当天结束时间
     * @return
     */
    public static Date getDayEnd(){
        Calendar cal=Calendar.getInstance();
        cal.set(Calendar.HOUR_OF_DAY, 23);//23点
        cal.set(Calendar.MINUTE, 59);//59分
        cal.set(Calendar.SECOND, 59);//59秒
        return cal.getTime();
    }
     
     
    /**
     * 获取昨天开始时间
     * @return
     */
    public static Date getBeginDayOfYesterday(){
        Calendar cal=Calendar.getInstance();
        cal.setTime(getDayBegin());//当天开始时间
        cal.add(Calendar.DAY_OF_MONTH, -1);//当天月份天数减1
        return cal.getTime();
    }
     
     
    /**
     * 获取昨天结束时间
     * @return
     */
    public static Date getEndDayOfYesterday(){
        Calendar cal=Calendar.getInstance();
        cal.setTime(getDayEnd());//当天结束时间
        cal.add(Calendar.DAY_OF_MONTH, -1);//当天月份天数减1
        return cal.getTime();
    }
     
     
    /**
     * 获取明天开始时间
     * @return
     */
    public static Date getBeginDayOfTomorrow(){
        Calendar cal=Calendar.getInstance();
        cal.setTime(getDayBegin());//当天开始时间
        cal.add(Calendar.DAY_OF_MONTH, 1);//当天月份天数加1
        return cal.getTime();
    }
     
     
    /**
     * 获取明天结束时间
     * @return
     */
    public static Date getEndDayOfTomorrow(){
        Calendar cal=Calendar.getInstance();
        cal.setTime(getDayEnd());//当天结束时间
        cal.add(Calendar.DAY_OF_MONTH, 1);//当天月份天数加1
        return cal.getTime();
    }
     
     
    /**
     * 获取某个日期的开始时间
     * @param d
     * @return
     */
    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
     * @param d
     * @return
     */
    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());
    }
     
     
    /**
     * 获取本周的开始时间
     * @return
     */
    @SuppressWarnings("unused")
    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
     * @return
     */
    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);
    }
     
     
    /**
     * 获取上周开始时间
     */
    @SuppressWarnings("unused")
    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
     * @return
     */
    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);
    }
     
     
    /**
     * 获取今年是哪一年
     * @return
     */
    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
     * @return
     */
    public static int getNowMonth() {
        Date date = new Date();
        GregorianCalendar gc=(GregorianCalendar)Calendar.getInstance();
        gc.setTime(date);
        return gc.get(2) + 1;
    }
     
     
    /**
     * 获取本月的开始时间
     * @return
     */
    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
     * @return
     */
    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
     * @return
     */
    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
     * @return
     */
    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());
    }
     
     
    /**
     * 获取本年的开始时间
     * @return
     */
    public static java.util.Date getBeginDayOfYear() {
        Calendar cal=Calendar.getInstance();
        cal.set(Calendar.YEAR, getNowYear());
        cal.set(Calendar.MONTH, Calendar.JANUARY);
        cal.set(Calendar.DATE, 1);
        return getDayStartTime(cal.getTime());
    }
     
     
    /**
     * 获取本年的结束时间
     * @return
     */
    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());
    }
     
     
    /**
     * 两个日期相减得到的天数
     * @param beginDate
     * @param endDate
     * @return
     */
    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
     * @param beginDate
     * @param endDate
     * @return
     */
    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起
     * @param beginDate
     * @param endDate
     * @return
     */
    public static Date max(Date beginDate, Date endDate) {
        if(beginDate==null) {
            return endDate;
        }
        if(endDate==null) {
            return beginDate;
        }
        if(beginDate.after(endDate)) {//beginDate日期大于endDate
           return beginDate;
        }
        return endDate;
    }
     
     
    /**
     * 获取两个日期中的最小日期
     * @param beginDate
     * @param endDate
     * @return
     */
    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;
    }
     
     
    /**
     * 获取某月该季度的第一个月
     * @param date
     * @return
     */
    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
     * @param date
     * @param i
     * @return
     */
    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
     * @param date
     * @param i
     * @return
     */
    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();
    }
     
     
     
    /**
   * 获取某年某月按天切片日期集合（某个月间隔多少天的日期集合）
   * @param beginYear
   * @param beginMonth
   * @param k
   * @return
   */
    @SuppressWarnings({ "unchecked", "rawtypes" })
    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;
    }
     
     
    /**
     * 获取某年某月到某年某月按天的切片日期集合（间隔天数的集合）
     * @param beginYear
     * @param beginMonth
     * @param endYear
     * @param endMonth
     * @param k
     * @return
     */
    @SuppressWarnings({ "rawtypes", "unchecked" })
    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;
    }
     
     
     
     
    //=================================时间格式转换==========================
     
    /**
     * date类型进行格式化输出（返回类型：String）
     * @param date
     * @return
     */
    public static String dateFormat(Date date) {
          SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
          String dateString = formatter.format(date);
          return dateString;
     }
 
     
    /**
     * 将"2015-08-31 21:08:06"型字符串转化为Date
     * @param str
     * @return
     * @throws ParseException
     */
    public static Date StringToDate(String str) throws ParseException{
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = (Date) formatter.parse(str);
        return date;
    }
     
     
    /**
     * 将CST时间类型字符串进行格式化输出
     * @param str
     * @return
     * @throws ParseException
     */
    public static String CSTFormat(String str) throws ParseException{
        SimpleDateFormat formatter = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy", Locale.US);
        Date date = (Date) formatter.parse(str);
        return dateFormat(date);
    }
     
     
     
    /**
     * 将long类型转化为Date
     * @param str
     * @return
     * @throws ParseException
     */
    public static Date LongToDare(long str) throws ParseException{      
        return new Date(str * 1000);  
    }
     
     
     
     
    //====================================其他常见日期操作方法======================
     
    /**
     * 判断当前日期是否在[startDate, endDate]区间
     * 
     * @param startDate 开始日期
     * @param endDate 结束日期
     * @author jqlin
     * @return
     */
    public static boolean isEffectiveDate(Date startDate, Date endDate){
        if(startDate == null || endDate == null){
            return false;
        }
        long currentTime = new Date().getTime();
        if(currentTime >= startDate.getTime() 
                && currentTime <= endDate.getTime()){
            return true;
        }
        return false;
    }
     
     
    /**
     * 得到二个日期间的间隔天数
     * @param secondString：后一个日期
     * @param firstString：前一个日期
     * @return
     */
    public static String getTwoDay(String secondString, String firstString) {
        SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
        long day = 0;
        try {
            java.util.Date secondTime = myFormatter.parse(secondString);
            java.util.Date firstTime = myFormatter.parse(firstString);
            day = (secondTime.getTime() - firstTime.getTime()) / (24 * 60 * 60 * 1000);
        } catch (Exception e) {
            return "";
        }
        return day + "";
    }
     
     
    /**
     * 时间前推或后推分钟,其中JJ表示分钟.
     * @param StringTime：时间
     * @param minute：分钟（有正负之分）
     * @return
     */
    public static String getPreTime(String StringTime, String minute) {
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String mydate1 = "";
        try {
            Date date1 = format.parse(StringTime);
            long Time = (date1.getTime() / 1000) + Integer.parseInt(minute) * 60;
            date1.setTime(Time * 1000);
            mydate1 = format.format(date1);
        } catch (Exception e) {
            return "";
        }
        return mydate1;
    }
     
     
    /**
     * 将短时间格式字符串转换为时间 yyyy-MM-dd 
     * 
     * @param strDate
     * @return
     */
    public static Date strToDate(String strDate) {
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
        ParsePosition pos = new ParsePosition(0);
        Date strtodate = formatter.parse(strDate, pos);
        return strtodate;
    }
     
     
     
    /**
     * 得到一个时间延后或前移几天的时间
     * @param nowdate：时间
     * @param delay：前移或后延的天数
     * @return
     */
    public static String getNextDay(String nowdate, String delay) {
        try{
            SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
            String mdate = "";
            Date d = strToDate(nowdate);
            long myTime = (d.getTime() / 1000) + Integer.parseInt(delay) * 24 * 60 * 60;
            d.setTime(myTime * 1000);
            mdate = format.format(d);
            return mdate;
        }catch(Exception e){
            return "";
        }
    }
     
     
    /**
     * 判断是否闰年
     * @param ddate
     * @return
     */
    public static boolean isLeapYear(String ddate) {
        /**
          * 详细设计： 1.被400整除是闰年，否则： 2.不能被4整除则不是闰年 3.能被4整除同时不能被100整除则是闰年
          * 3.能被4整除同时能被100整除则不是闰年
         */
        Date d = strToDate(ddate);
        GregorianCalendar gc = (GregorianCalendar) Calendar.getInstance();
        gc.setTime(d);
        int year = gc.get(Calendar.YEAR);
        if ((year % 400) == 0){
            return true;
        }else if ((year % 4) == 0){
           if ((year % 100) == 0){
               return false;
           }else{
               return true;
           }
        }else{
            return false;
        }
    }
     
     
    /**
     * 返回美国时间格式
     * @param str
     * @return
     */
    public static String getEDate(String str) {
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
        ParsePosition pos = new ParsePosition(0);
        Date strtodate = formatter.parse(str, pos);
        String j = strtodate.toString();
        String[] k = j.split(" ");
        return k[2] + k[1].toUpperCase() + k[5].substring(2, 4);
    }
 
     
    /**
     * 判断二个时间是否在同一个周
     * @param date1
     * @param date2
     * @return
     */
    public static boolean isSameWeekDates(Date date1, Date date2) {
        Calendar cal1 = Calendar.getInstance();
        Calendar cal2 = Calendar.getInstance();
        cal1.setTime(date1);
        cal2.setTime(date2);
        int subYear = cal1.get(Calendar.YEAR) - cal2.get(Calendar.YEAR);
        if(0 == subYear) {
            if (cal1.get(Calendar.WEEK_OF_YEAR) == cal2.get(Calendar.WEEK_OF_YEAR)){
                return true;
            }
        }else if(1 == subYear && 11 == cal2.get(Calendar.MONTH)) {
            // 如果12月的最后一周横跨来年第一周的话则最后一周即算做来年的第一周
            if (cal1.get(Calendar.WEEK_OF_YEAR) == cal2.get(Calendar.WEEK_OF_YEAR)){
                return true;
            }
        }else if (-1 == subYear && 11 == cal1.get(Calendar.MONTH)) {
            if (cal1.get(Calendar.WEEK_OF_YEAR) == cal2.get(Calendar.WEEK_OF_YEAR)){
                return true;
            }
        }
        return false;
    }
     
     
     
    /**
     * 产生周序列,即得到当前时间所在的年度是第几周
     * @return
     */
    public static String getSeqWeek() {
        Calendar c = Calendar.getInstance(Locale.CHINA);
        String week = Integer.toString(c.get(Calendar.WEEK_OF_YEAR));
        if (week.length() == 1)
        week = "0" + week;
        String year = Integer.toString(c.get(Calendar.YEAR));
        return year +"年第"+ week+"周";
    }
     
     
    /**
     * 获得一个日期所在的周的星期几的日期，如要找出2002年2月3日所在周的星期一是几号
     * @param sdate：日期
     * @param num：星期几（星期天是一周的第一天）
     * @return
     */
    public static String getWeek(String sdate, String num) {
        // 再转换为时间
        Date dd = strToDate(sdate);
        Calendar c = Calendar.getInstance();
        c.setTime(dd);
        if (num.equals("1")) // 返回星期一所在的日期
        c.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY);
        else if (num.equals("2")) // 返回星期二所在的日期
        c.set(Calendar.DAY_OF_WEEK, Calendar.TUESDAY);
        else if (num.equals("3")) // 返回星期三所在的日期
        c.set(Calendar.DAY_OF_WEEK, Calendar.WEDNESDAY);
        else if (num.equals("4")) // 返回星期四所在的日期
        c.set(Calendar.DAY_OF_WEEK, Calendar.THURSDAY);
        else if (num.equals("5")) // 返回星期五所在的日期
        c.set(Calendar.DAY_OF_WEEK, Calendar.FRIDAY);
        else if (num.equals("6")) // 返回星期六所在的日期
        c.set(Calendar.DAY_OF_WEEK, Calendar.SATURDAY);
        else if (num.equals("0")) // 返回星期日所在的日期
        c.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
        return new SimpleDateFormat("yyyy-MM-dd").format(c.getTime());
    }
     
     
    /**
     * 根据一个日期，返回是星期几的字符串
     * @param sdate
     * @return
     */
    public static String getWeek(String sdate) {
        // 再转换为时间
        Date date = strToDate(sdate);
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        // int hour=c.get(Calendar.DAY_OF_WEEK);
        // hour中存的就是星期几了，其范围 1~7
        // 1=星期日 7=星期六，其他类推
        return new SimpleDateFormat("EEEE").format(c.getTime());
    }
     
     
    /**
     * 根据一个日期，返回是星期几的字符串
     * @param sdate
     * @return
     */
    public static String getWeekStr(String sdate){
        String str = "";
        str = getWeek(sdate);
        if("1".equals(str)){
            str = "星期日";
        }else if("2".equals(str)){
            str = "星期一";
        }else if("3".equals(str)){
            str = "星期二";
        }else if("4".equals(str)){
            str = "星期三";
        }else if("5".equals(str)){
            str = "星期四";
        }else if("6".equals(str)){
            str = "星期五";
        }else if("7".equals(str)){
            str = "星期六";
        }
        return str;
    }
     
     
    /**
     * 两个时间之间的天数
     * @param date1
     * @param date2
     * @return
     */
    public static long getDays(String date1, String date2) {
        if (date1 == null || date1.equals(""))
            return 0;
        if (date2 == null || date2.equals(""))
            return 0;
        // 转换为标准时间
        SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
        java.util.Date date = null;
        java.util.Date mydate = null;
        try {
            date = myFormatter.parse(date1);
            mydate = myFormatter.parse(date2);
        } catch (Exception e) {
        }
        long day = (date.getTime() - mydate.getTime()) / (24 * 60 * 60 * 1000);
        return day;
    }
     
     
    /**
     * 形成如下的日历 ， 根据传入的一个时间返回一个结构 星期日 星期一 星期二 星期三 星期四 星期五 星期六 下面是当月的各个时间
     * 此函数返回该日历第一行星期日所在的日期
     * @param sdate
     * @return
     */
    public static String getNowMonth(String sdate) {
        // 取该时间所在月的一号
        sdate = sdate.substring(0, 8) + "01";
 
        // 得到这个月的1号是星期几
        Date date = strToDate(sdate);
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        int u = c.get(Calendar.DAY_OF_WEEK);
        String newday = getNextDay(sdate, (1 - u) + "");
        return newday;
    }
     
     
    /**
     * 根据用户传入的时间表示格式，返回当前时间的格式 如果是yyyyMMdd，注意字母y不能大写
     * @param sformat
     * @return
     */
    public static String getUserDate(String sformat) {
        Date currentTime = new Date();
        SimpleDateFormat formatter = new SimpleDateFormat(sformat);
        String dateString = formatter.format(currentTime);
        return dateString;
    }
     
     
    /**
     * 返回一个i位数的随机数
     * @param i
     * @return
     */
    public static String getRandom(int i) {
        Random jjj = new Random();
        // int suiJiShu = jjj.nextInt(9);
        if (i == 0)
            return "";
        String jj = "";
        for (int k = 0; k < i; k++) {
            jj = jj + jjj.nextInt(9);
        }
        return jj;
    }
     
     
    /**
     * 取得数据库主键 生成格式为yyyymmddhhmmss+k位随机数
     * @param k：表示是取几位随机数，可以自己定
     * @return
     */
    public static String getNo(int k) {
        return getUserDate("yyyyMMddhhmmss") + getRandom(k);
    }
     
     
    public static void main(String[] args) {
        System.out.println(getNo(8));
    }
}