Java中SimpleDateFormat用法详解——获得常用时间表示法(二)

Java代码

import   java.text.SimpleDateFormat;

SimpleDateFormat   formatter   =   new   SimpleDateFormat   ("yyyy年MM月dd日   HH:mm:ss     ");
 Date   curDate   =   new   Date(System.currentTimeMillis());//获取当前时间
String   str   =   formatter.format(curDate);

可以获取当前的年月时分,也可以分开写:

SimpleDateFormat   sDateFormat   =   new   SimpleDateFormat("yyyy-MM-dd   hh:mm:ss");
String   date   =   sDateFormat.format(new   java.util.Date());

 如果想获取当前的年月,则可以这样写(只获取时间或秒种一样):

Java代码

SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM");
String date=sdf.format(new java.util.Date());

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Java代码

package com.hefeng.test;


import java.text.DateFormat;
import java.text.ParsePosition;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

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);
  }
}

评论

1 楼 zhaokui 2012-06-06  

很好，很好