date

public class DateUtil {  
    private static Calendar _calendar = Calendar.getInstance(); // 用于日期计算  
 
    private static long MSEC_EVERYDAY = 86400000L; // 一天的微秒数  
 
    private static int rawOffset = TimeZone.getDefault().getRawOffset();  
 
    /** 
     * 将日期转换为1970-01-01后的天数 
     *  
     * @param Date 
     *            theDate 要计算天数的日期 
     * @return int 所传入日期与1970-01-01相差的天数 
     */ 
    public static int dateToDay(Date theDate) {  
        return (int) ((theDate.getTime() + rawOffset) / MSEC_EVERYDAY);  
    }  
 
    /** 
     * 将1970-01-01后的天数转换为日期 
     *  
     * @param int 
     *            要取的日期与1970-01-01相差的天数 
     * @return Date theDate 与1970-01-01相差相应天数的日期 
     */ 
    public static Date dayToDate(int day) {  
        return new Date(day * MSEC_EVERYDAY);  
    }  
 
    /** 
     * 取今天与1970-01-01相差的天数 
     *  
     * @return int 取今天与1970-01-01相差的天数 
     */ 
    public static int toDay() {  
        return (int) ((System.currentTimeMillis() + rawOffset) / MSEC_EVERYDAY);  
    }  
 
    /** 
     * 将日期转换为年月日字符串 
     *  
     * @param int 
     *            theDay 与1970-01-01相差的天数 
     * @return String 对应日期年月日形式的字符串 
     */ 
    public static String getYMD(int theDay) {  
        _calendar.setTime(dayToDate(theDay));  
        return _calendar.get(Calendar.YEAR) % 100 + "/" 
                + (_calendar.get(Calendar.MONTH) + 1 > 9 ? "" : "0")  
                + (_calendar.get(Calendar.MONTH) + 1) + "/" 
                + (_calendar.get(Calendar.DATE) > 9 ? "" : "0")  
                + _calendar.get(Calendar.DATE);  
    }  
 
    /** 
     * 将日期转换为年月字符串 
     *  
     * @param int 
     *            theDay 与1970-01-01相差的天数 
     * @return String 对应日期年月形式的字符串 
     */ 
    public static String getYM(int theDay) {  
        _calendar.setTime(dayToDate(theDay));  
        return _calendar.get(Calendar.YEAR) + "/" 
                + (_calendar.get(Calendar.MONTH) + 1 > 9 ? "" : "0")  
                + (_calendar.get(Calendar.MONTH) + 1);  
    }  
 
    /** 
     * 将日期转换为月日字符串 
     *  
     * @param int 
     *            theDay 与1970-01-01相差的天数 
     * @return String 对应日期月日形式的字符串 
     */ 
    public static String getMD(int theDay) {  
        _calendar.setTime(dayToDate(theDay));  
        return (_calendar.get(Calendar.MONTH) + 1 > 9 ? "" : "0")  
                + (_calendar.get(Calendar.MONTH) + 1) + "/" 
                + (_calendar.get(Calendar.DATE) > 9 ? "" : "0")  
                + _calendar.get(Calendar.DATE);  
    }  
 
    /** 
     * 将日期转换为当月一号 
     *  
     * @param int 
     *            theDay 与1970-01-01相差的天数 
     * @return int 对应日期所在月份第一天与1970-01-01相差的天数 
     */ 
    public static int getMonthFirstDay(int theDay) {  
        _calendar.setTime(dayToDate(theDay));  
        _calendar.set(Calendar.DAY_OF_MONTH, 1);  
        return (int) (dateToDay(_calendar.getTime()));  
    }  
 
    /** 
     * 取日期所在年份 
     *  
     * @param int 
     *            theDay 与1970-01-01相差的天数 
     * @return int 对应日期所在年份 
     */ 
    public static int getYear(int theDay) {  
        _calendar.setTime(dayToDate(theDay));  
        return _calendar.get(Calendar.YEAR);  
    }  
 
    /** 
     * 取日期所在月份 
     *  
     * @param int 
     *            theDay 与1970-01-01相差的天数 
     * @return int 对应日期所在月份 
     */ 
    public static int getMonth(int theDay) {  
        _calendar.setTime(dayToDate(theDay));  
        return _calendar.get(Calendar.MONTH);  
    }  
 
    /** 
     * 取日期所在周次 
     *  
     * @param int 
     *            theDay 与1970-01-01相差的天数 
     * @return int 对应日期所在周次 
     */ 
    public static int getWeek(int theDay) {  
        // 1971-01-03是星期日,从该日开始计算周次  
        _calendar.setTime(dayToDate(theDay));  
        return (int) ((_calendar.getTime().getTime() - 172800000L) / 604800000L);  
    }  
 
} 



public class TimeTest {  
    //用来全局控制 上一周，本周，下一周的周数变化  
    private  int weeks = 0;  
    private int MaxDate;//一月最大天数  
    private int MaxYear;//一年最大天数  
      
      
    /** 
     * @param args 
     */ 
    public static void main(String[] args) {  
        TimeTest tt = new TimeTest();  
        System.out.println("获取当天日期:"+tt.getNowTime("yyyy-MM-dd"));  
        System.out.println("获取本周一日期:"+tt.getMondayOFWeek());  
        System.out.println("获取本周日的日期~:"+tt.getCurrentWeekday());  
        System.out.println("获取上周一日期:"+tt.getPreviousWeekday());  
        System.out.println("获取上周日日期:"+tt.getPreviousWeekSunday());  
        System.out.println("获取下周一日期:"+tt.getNextMonday());  
        System.out.println("获取下周日日期:"+tt.getNextSunday());  
        System.out.println("获得相应周的周六的日期:"+tt.getNowTime("yyyy-MM-dd"));  
        System.out.println("获取本月第一天日期:"+tt.getFirstDayOfMonth());  
        System.out.println("获取本月最后一天日期:"+tt.getDefaultDay());  
        System.out.println("获取上月第一天日期:"+tt.getPreviousMonthFirst());  
        System.out.println("获取上月最后一天的日期:"+tt.getPreviousMonthEnd());  
        System.out.println("获取下月第一天日期:"+tt.getNextMonthFirst());  
        System.out.println("获取下月最后一天日期:"+tt.getNextMonthEnd());  
        System.out.println("获取本年的第一天日期:"+tt.getCurrentYearFirst());  
        System.out.println("获取本年最后一天日期:"+tt.getCurrentYearEnd());  
        System.out.println("获取去年的第一天日期:"+tt.getPreviousYearFirst());  
        System.out.println("获取去年的最后一天日期:"+tt.getPreviousYearEnd());  
        System.out.println("获取明年第一天日期:"+tt.getNextYearFirst());  
        System.out.println("获取明年最后一天日期:"+tt.getNextYearEnd());  
        System.out.println("获取本季度第一天到最后一天:"+tt.getThisSeasonTime(11));  
        System.out.println("获取两个日期之间间隔天数2008-12-1~2008-9.29:"+TimeTest.getTwoDay("2008-12-1","2008-9-29"));  
    }  
      
      
    /** 
        * 得到二个日期间的间隔天数 
        */ 
    public static String getTwoDay(String sj1, String sj2) {  
        SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");  
        long day = 0;  
        try {  
         java.util.Date date = myFormatter.parse(sj1);  
         java.util.Date mydate = myFormatter.parse(sj2);  
         day = (date.getTime() - mydate.getTime()) / (24 * 60 * 60 * 1000);  
        } catch (Exception e) {  
         return "";  
        }  
        return day + "";  
    }  
 
 
    /** 
        * 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 = TimeTest.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());  
    }  
 
    /** 
        * 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;  
    }  
 
    /** 
        * 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;  
    }  
 
 
 
      
    // 计算当月最后一天,返回字符串  
    public String getDefaultDay(){    
       String str = "";  
       SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");      
 
       Calendar lastDate = Calendar.getInstance();  
       lastDate.set(Calendar.DATE,1);//设为当前月的1号  
       lastDate.add(Calendar.MONTH,1);//加一个月，变为下月的1号  
       lastDate.add(Calendar.DATE,-1);//减去一天，变为当月最后一天  
         
       str=sdf.format(lastDate.getTime());  
       return str;    
    }  
      
    // 上月第一天  
    public String getPreviousMonthFirst(){    
       String str = "";  
       SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");      
 
       Calendar lastDate = Calendar.getInstance();  
       lastDate.set(Calendar.DATE,1);//设为当前月的1号  
       lastDate.add(Calendar.MONTH,-1);//减一个月，变为下月的1号  
       //lastDate.add(Calendar.DATE,-1);//减去一天，变为当月最后一天  
         
       str=sdf.format(lastDate.getTime());  
       return str;    
    }  
      
    //获取当月第一天  
    public String getFirstDayOfMonth(){    
       String str = "";  
       SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");      
 
       Calendar lastDate = Calendar.getInstance();  
       lastDate.set(Calendar.DATE,1);//设为当前月的1号  
       str=sdf.format(lastDate.getTime());  
       return str;    
    }  
      
    // 获得本周星期日的日期    
    public String getCurrentWeekday() {  
        weeks = 0;  
        int mondayPlus = this.getMondayPlus();  
        GregorianCalendar currentDate = new GregorianCalendar();  
        currentDate.add(GregorianCalendar.DATE, mondayPlus+6);  
        Date monday = currentDate.getTime();  
          
        DateFormat df = DateFormat.getDateInstance();  
        String preMonday = df.format(monday);  
        return preMonday;  
    }  
      
      
    //获取当天时间   
    public String getNowTime(String dateformat){  
        Date   now   =   new   Date();     
        SimpleDateFormat   dateFormat   =   new   SimpleDateFormat(dateformat);//可以方便地修改日期格式     
        String  hehe  = dateFormat.format(now);     
        return hehe;  
    }  
      
    // 获得当前日期与本周日相差的天数  
    private int getMondayPlus() {  
        Calendar cd = Calendar.getInstance();  
        // 获得今天是一周的第几天，星期日是第一天，星期二是第二天......  
        int dayOfWeek = cd.get(Calendar.DAY_OF_WEEK)-1;         //因为按中国礼拜一作为第一天所以这里减1  
        if (dayOfWeek == 1) {  
            return 0;  
        } else {  
            return 1 - dayOfWeek;  
        }  
    }  
      
    //获得本周一的日期  
    public String getMondayOFWeek(){  
         weeks = 0;  
         int mondayPlus = this.getMondayPlus();  
         GregorianCalendar currentDate = new GregorianCalendar();  
         currentDate.add(GregorianCalendar.DATE, mondayPlus);  
         Date monday = currentDate.getTime();  
           
         DateFormat df = DateFormat.getDateInstance();  
         String preMonday = df.format(monday);  
         return preMonday;  
    }  
      
  //获得相应周的周六的日期  
    public String getSaturday() {  
        int mondayPlus = this.getMondayPlus();  
        GregorianCalendar currentDate = new GregorianCalendar();  
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 * weeks + 6);  
        Date monday = currentDate.getTime();  
        DateFormat df = DateFormat.getDateInstance();  
        String preMonday = df.format(monday);  
        return preMonday;  
    }  
      
// 获得上周星期日的日期  
    public String getPreviousWeekSunday() {  
        weeks=0;  
        weeks--;  
        int mondayPlus = this.getMondayPlus();  
        GregorianCalendar currentDate = new GregorianCalendar();  
        currentDate.add(GregorianCalendar.DATE, mondayPlus+weeks);  
        Date monday = currentDate.getTime();  
        DateFormat df = DateFormat.getDateInstance();  
        String preMonday = df.format(monday);  
        return preMonday;  
    }  
 
// 获得上周星期一的日期  
    public String getPreviousWeekday() {  
        weeks--;  
        int mondayPlus = this.getMondayPlus();  
        GregorianCalendar currentDate = new GregorianCalendar();  
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 * weeks);  
        Date monday = currentDate.getTime();  
        DateFormat df = DateFormat.getDateInstance();  
        String preMonday = df.format(monday);  
        return preMonday;  
    }  
      
    // 获得下周星期一的日期  
    public String getNextMonday() {  
        weeks++;  
        int mondayPlus = this.getMondayPlus();  
        GregorianCalendar currentDate = new GregorianCalendar();  
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7);  
        Date monday = currentDate.getTime();  
        DateFormat df = DateFormat.getDateInstance();  
        String preMonday = df.format(monday);  
        return preMonday;  
    }  
      
// 获得下周星期日的日期  
    public String getNextSunday() {  
          
        int mondayPlus = this.getMondayPlus();  
        GregorianCalendar currentDate = new GregorianCalendar();  
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7+6);  
        Date monday = currentDate.getTime();  
        DateFormat df = DateFormat.getDateInstance();  
        String preMonday = df.format(monday);  
        return preMonday;  
    }  
      
      
      
    private int getMonthPlus(){  
        Calendar cd = Calendar.getInstance();  
        int monthOfNumber = cd.get(Calendar.DAY_OF_MONTH);  
        cd.set(Calendar.DATE, 1);//把日期设置为当月第一天   
        cd.roll(Calendar.DATE, -1);//日期回滚一天，也就是最后一天   
        MaxDate=cd.get(Calendar.DATE);   
        if(monthOfNumber == 1){  
            return -MaxDate;  
        }else{  
            return 1-monthOfNumber;  
        }  
    }  
      
  //获得上月最后一天的日期  
    public String getPreviousMonthEnd(){  
        String str = "";  
       SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");      
 
       Calendar lastDate = Calendar.getInstance();  
      lastDate.add(Calendar.MONTH,-1);//减一个月  
      lastDate.set(Calendar.DATE, 1);//把日期设置为当月第一天   
      lastDate.roll(Calendar.DATE, -1);//日期回滚一天，也就是本月最后一天   
       str=sdf.format(lastDate.getTime());  
       return str;    
    }  
      
  //获得下个月第一天的日期  
    public String getNextMonthFirst(){  
        String str = "";  
       SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");      
 
       Calendar lastDate = Calendar.getInstance();  
      lastDate.add(Calendar.MONTH,1);//减一个月  
      lastDate.set(Calendar.DATE, 1);//把日期设置为当月第一天   
       str=sdf.format(lastDate.getTime());  
       return str;    
    }  
      
  //获得下个月最后一天的日期  
    public String getNextMonthEnd(){  
        String str = "";  
       SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");      
 
       Calendar lastDate = Calendar.getInstance();  
      lastDate.add(Calendar.MONTH,1);//加一个月  
      lastDate.set(Calendar.DATE, 1);//把日期设置为当月第一天   
      lastDate.roll(Calendar.DATE, -1);//日期回滚一天，也就是本月最后一天   
       str=sdf.format(lastDate.getTime());  
       return str;    
    }  
      
    //获得明年最后一天的日期  
    public String getNextYearEnd(){  
        String str = "";  
       SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");      
 
      Calendar lastDate = Calendar.getInstance();  
      lastDate.add(Calendar.YEAR,1);//加一个年  
      lastDate.set(Calendar.DAY_OF_YEAR, 1);  
     lastDate.roll(Calendar.DAY_OF_YEAR, -1);  
       str=sdf.format(lastDate.getTime());  
       return str;    
    }  
      
  //获得明年第一天的日期  
    public String getNextYearFirst(){  
        String str = "";  
       SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");      
 
      Calendar lastDate = Calendar.getInstance();  
      lastDate.add(Calendar.YEAR,1);//加一个年  
      lastDate.set(Calendar.DAY_OF_YEAR, 1);  
           str=sdf.format(lastDate.getTime());  
      return str;    
          
    }  
      
  //获得本年有多少天  
    private int getMaxYear(){  
        Calendar cd = Calendar.getInstance();  
        cd.set(Calendar.DAY_OF_YEAR,1);//把日期设为当年第一天  
        cd.roll(Calendar.DAY_OF_YEAR,-1);//把日期回滚一天。  
        int MaxYear = cd.get(Calendar.DAY_OF_YEAR);   
        return MaxYear;  
    }  
      
    private int getYearPlus(){  
        Calendar cd = Calendar.getInstance();  
        int yearOfNumber = cd.get(Calendar.DAY_OF_YEAR);//获得当天是一年中的第几天  
        cd.set(Calendar.DAY_OF_YEAR,1);//把日期设为当年第一天  
        cd.roll(Calendar.DAY_OF_YEAR,-1);//把日期回滚一天。  
        int MaxYear = cd.get(Calendar.DAY_OF_YEAR);  
        if(yearOfNumber == 1){  
            return -MaxYear;  
        }else{  
            return 1-yearOfNumber;  
        }  
    }  
  //获得本年第一天的日期  
    public String getCurrentYearFirst(){  
        int yearPlus = this.getYearPlus();  
        GregorianCalendar currentDate = new GregorianCalendar();  
        currentDate.add(GregorianCalendar.DATE,yearPlus);  
        Date yearDay = currentDate.getTime();  
        DateFormat df = DateFormat.getDateInstance();  
        String preYearDay = df.format(yearDay);  
        return preYearDay;  
    }  
      
      
  //获得本年最后一天的日期 *  
    public String getCurrentYearEnd(){  
        Date date = new Date();  
        SimpleDateFormat   dateFormat   =   new   SimpleDateFormat("yyyy");//可以方便地修改日期格式     
        String  years  = dateFormat.format(date);     
        return years+"-12-31";  
    }  
      
      
  //获得上年第一天的日期 *  
    public String getPreviousYearFirst(){  
        Date date = new Date();  
        SimpleDateFormat   dateFormat   =   new   SimpleDateFormat("yyyy");//可以方便地修改日期格式     
        String  years  = dateFormat.format(date); int years_value = Integer.parseInt(years);    
        years_value--;  
        return years_value+"-1-1";  
    }  
      
  //获得上年最后一天的日期  
    public String getPreviousYearEnd(){  
        weeks--;  
        int yearPlus = this.getYearPlus();  
        GregorianCalendar currentDate = new GregorianCalendar();  
        currentDate.add(GregorianCalendar.DATE,yearPlus+MaxYear*weeks+(MaxYear-1));  
        Date yearDay = currentDate.getTime();  
        DateFormat df = DateFormat.getDateInstance();  
        String preYearDay = df.format(yearDay);  
        getThisSeasonTime(11);  
        return preYearDay;  
    }  
      
  //获得本季度  
    public String getThisSeasonTime(int month){  
        int array[][] = {{1,2,3},{4,5,6},{7,8,9},{10,11,12}};  
        int season = 1;  
        if(month>=1&&month<=3){  
            season = 1;  
        }  
        if(month>=4&&month<=6){  
            season = 2;  
        }  
        if(month>=7&&month<=9){  
            season = 3;  
        }  
        if(month>=10&&month<=12){  
            season = 4;  
        }  
        int start_month = array[season-1][0];  
        int end_month = array[season-1][2];  
          
        Date date = new Date();  
        SimpleDateFormat   dateFormat   =   new   SimpleDateFormat("yyyy");//可以方便地修改日期格式     
        String  years  = dateFormat.format(date);     
        int years_value = Integer.parseInt(years);  
          
        int start_days =1;//years+"-"+String.valueOf(start_month)+"-1";//getLastDayOfMonth(years_value,start_month);  
        int end_days = getLastDayOfMonth(years_value,end_month);  
        String seasonDate = years_value+"-"+start_month+"-"+start_days+";"+years_value+"-"+end_month+"-"+end_days;  
        return seasonDate;  
          
    }  
      
    /** 
     * 获取某年某月的最后一天 
     * @param year 年 
     * @param month 月 
     * @return 最后一天 
     */ 
   private int getLastDayOfMonth(int year, int month) {  
         if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 
                   || month == 10 || month == 12) {  
               return 31;  
         }  
         if (month == 4 || month == 6 || month == 9 || month == 11) {  
               return 30;  
         }  
         if (month == 2) {  
               if (isLeapYear(year)) {  
                   return 29;  
               } else {  
                   return 28;  
               }  
         }  
         return 0;  
   }  
   /** 
    * 是否闰年 
    * @param year 年 
    * @return  
    */ 
  public boolean isLeapYear(int year) {  
        return (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);  
  }  
}