Java 学习笔记 (三) Java 日期类型

以下内容摘自:  https://www.cnblogs.com/crazylqy/p/4172324.html

import java.sql.Timestamp;
import java.text.ParsePosition; 
import java.text.SimpleDateFormat; 
import java.util.Calendar; 
import java.util.Date; 
import java.util.GregorianCalendar; 
import java.util.regex.Pattern; 
import org.apache.commons.logging.Log; 
import org.apache.commons.logging.LogFactory; 
  
  
public class DateUtils { 
    protected static Log logger = LogFactory.getLog(DateUtils.class); 
  
    // 格式：年－月－日 小时：分钟：秒 
    public static final String FORMAT_ONE = "yyyy-MM-dd HH:mm:ss"; 
  
    // 格式：年－月－日 小时：分钟 
    public static final String FORMAT_TWO = "yyyy-MM-dd HH:mm"; 
  
    // 格式：年月日 小时分钟秒 
    public static final String FORMAT_THREE = "yyyyMMdd-HHmmss"; 
  
    // 格式：年－月－日 
    public static final String LONG_DATE_FORMAT = "yyyy-MM-dd"; 
  
    // 格式：月－日 
    public static final String SHORT_DATE_FORMAT = "MM-dd"; 
  
    // 格式：小时：分钟：秒 
    public static final String LONG_TIME_FORMAT = "HH:mm:ss"; 
  
    //格式：年-月 
    public static final String MONTG_DATE_FORMAT = "yyyy-MM"; 
  
    // 年的加减 
    public static final int SUB_YEAR = Calendar.YEAR; 
  
    // 月加减 
    public static final int SUB_MONTH = Calendar.MONTH; 
  
    // 天的加减 
    public static final int SUB_DAY = Calendar.DATE; 
  
    // 小时的加减 
    public static final int SUB_HOUR = Calendar.HOUR; 
  
    // 分钟的加减 
    public static final int SUB_MINUTE = Calendar.MINUTE; 
  
    // 秒的加减 
    public static final int SUB_SECOND = Calendar.SECOND; 
  
    static final String dayNames[] = { "星期日", "星期一", "星期二", "星期三", "星期四","星期五", "星期六" }; 
  
    @SuppressWarnings("unused") 
    private static final SimpleDateFormat timeFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); 
  
    public DateUtils() {} 
  
    /** 
     * 把符合日期格式的字符串转换为日期类型 
     *  
     * @param dateStr 
     * @return 
     */ 
    public static java.util.Date stringtoDate(String dateStr, String format) { 
        Date d = null; 
        SimpleDateFormat formater = new SimpleDateFormat(format); 
        try { 
            formater.setLenient(false); 
            d = formater.parse(dateStr); 
        } catch (Exception e) { 
            // log.error(e); 
            d = null; 
        } 
        return d; 
    } 
  
    /** 
     * 把符合日期格式的字符串转换为日期类型 
     */ 
    public static java.util.Date stringtoDate(String dateStr, String format, 
            ParsePosition pos) { 
        Date d = null; 
        SimpleDateFormat formater = new SimpleDateFormat(format); 
        try { 
            formater.setLenient(false); 
            d = formater.parse(dateStr, pos); 
        } catch (Exception e) { 
            d = null; 
        } 
        return d; 
    } 
  
    /** 
     * 把日期转换为字符串 
     *  
     * @param date 
     * @return 
     */ 
    public static String dateToString(java.util.Date date, String format) { 
        String result = ""; 
        SimpleDateFormat formater = new SimpleDateFormat(format); 
        try { 
            result = formater.format(date); 
        } catch (Exception e) { 
            // log.error(e); 
        } 
        return result; 
    } 
  
    /** 
     * 获取当前时间的指定格式 
     *  
     * @param format 
     * @return 
     */ 
    public static String getCurrDate(String format) { 
        return dateToString(new Date(), format); 
    } 
  
    /** 
     *  
     * @param dateStr 
     * @param amount 
     * @return 
     */ 
    public static String dateSub(int dateKind, String dateStr, int amount) { 
        Date date = stringtoDate(dateStr, FORMAT_ONE); 
        Calendar calendar = Calendar.getInstance(); 
        calendar.setTime(date); 
        calendar.add(dateKind, amount); 
        return dateToString(calendar.getTime(), FORMAT_ONE); 
    } 
  
    /** 
     * 两个日期相减 
     *  
     * @param firstTime 
     * @param secTime 
     * @return 相减得到的秒数 
     */ 
    public static long timeSub(String firstTime, String secTime) { 
        long first = stringtoDate(firstTime, FORMAT_ONE).getTime(); 
        long second = stringtoDate(secTime, FORMAT_ONE).getTime(); 
        return (second - first) / 1000; 
    } 
  
    /** 
     * 获得某月的天数 
     *  
     * @param year 
     *          int 
     * @param month 
     *          int 
     * @return int 
     */ 
    public static int getDaysOfMonth(String year, String month) { 
        int days = 0; 
        if (month.equals("1") || month.equals("3") || month.equals("5") 
                || month.equals("7") || month.equals("8") || month.equals("10") 
                || month.equals("12")) { 
            days = 31; 
        } else if (month.equals("4") || month.equals("6") || month.equals("9") 
                || month.equals("11")) { 
            days = 30; 
        } else { 
            if ((Integer.parseInt(year) % 4 == 0 && Integer.parseInt(year) % 100 != 0) 
                    || Integer.parseInt(year) % 400 == 0) { 
                days = 29; 
            } else { 
                days = 28; 
            } 
        } 
  
        return days; 
    } 
  
    /** 
     * 获取某年某月的天数 
     *  
     * @param year 
     *          int 
     * @param month 
     *          int 月份[1-12] 
     * @return int 
     */ 
    public static int getDaysOfMonth(int year, int month) { 
        Calendar calendar = Calendar.getInstance(); 
        calendar.set(year, month - 1, 1); 
        return calendar.getActualMaximum(Calendar.DAY_OF_MONTH); 
    } 
  
    /** 
     * 获得当前日期 
     *  
     * @return int 
     */ 
    public static int getToday() { 
        Calendar calendar = Calendar.getInstance(); 
        return calendar.get(Calendar.DATE); 
    } 
  
    /** 
     * 获得当前月份 
     *  
     * @return int 
     */ 
    public static int getToMonth() { 
        Calendar calendar = Calendar.getInstance(); 
        return calendar.get(Calendar.MONTH) + 1; 
    } 
  
    /** 
     * 获得当前年份 
     *  
     * @return int 
     */ 
    public static int getToYear() { 
        Calendar calendar = Calendar.getInstance(); 
        return calendar.get(Calendar.YEAR); 
    } 
  
    /** 
     * 返回日期的天 
     *  
     * @param date 
     *          Date 
     * @return int 
     */ 
    public static int getDay(Date date) { 
        Calendar calendar = Calendar.getInstance(); 
        calendar.setTime(date); 
        return calendar.get(Calendar.DATE); 
    } 
  
    /** 
     * 返回日期的年 
     *  
     * @param date 
     *          Date 
     * @return int 
     */ 
    public static int getYear(Date date) { 
        Calendar calendar = Calendar.getInstance(); 
        calendar.setTime(date); 
        return calendar.get(Calendar.YEAR); 
    } 
  
    /** 
     * 返回日期的月份，1-12 
     *  
     * @param date 
     *          Date 
     * @return int 
     */ 
    public static int getMonth(Date date) { 
        Calendar calendar = Calendar.getInstance(); 
        calendar.setTime(date); 
        return calendar.get(Calendar.MONTH) + 1; 
    } 
  
    /** 
     * 计算两个日期相差的天数，如果date2 > date1 返回正数，否则返回负数 
     *  
     * @param date1 
     *          Date 
     * @param date2 
     *          Date 
     * @return long 
     */ 
    public static long dayDiff(Date date1, Date date2) { 
        return (date2.getTime() - date1.getTime()) / 86400000; 
    } 
  
    /** 
     * 比较两个日期的年差 
     *  
     * @param befor 
     * @param after 
     * @return 
     */ 
    public static int yearDiff(String before, String after) { 
        Date beforeDay = stringtoDate(before, LONG_DATE_FORMAT); 
        Date afterDay = stringtoDate(after, LONG_DATE_FORMAT); 
        return getYear(afterDay) - getYear(beforeDay); 
    } 
  
    /** 
     * 比较指定日期与当前日期的差 
     *  
     * @param befor 
     * @param after 
     * @return 
     */ 
    public static int yearDiffCurr(String after) { 
        Date beforeDay = new Date(); 
        Date afterDay = stringtoDate(after, LONG_DATE_FORMAT); 
        return getYear(beforeDay) - getYear(afterDay); 
    } 
      
    /** 
     * 比较指定日期与当前日期的差 
     * @param before 
     * @return 
     */ 
    public static long dayDiffCurr(String before) { 
        Date currDate = DateUtils.stringtoDate(currDay(), LONG_DATE_FORMAT); 
        Date beforeDate = stringtoDate(before, LONG_DATE_FORMAT); 
        return (currDate.getTime() - beforeDate.getTime()) / 86400000; 
  
    } 
  
    /** 
     * 获取每月的第一周 
     * @param year 
     * @param month 
     * @return 
     */ 
    public static int getFirstWeekdayOfMonth(int year, int month) { 
        Calendar c = Calendar.getInstance(); 
        c.setFirstDayOfWeek(Calendar.SATURDAY); // 星期天为第一天 
        c.set(year, month - 1, 1); 
        return c.get(Calendar.DAY_OF_WEEK); 
    } 
  
    /** 
     * 获取每月的最后一周 
     * @param year 
     * @param month 
     * @return 
     */ 
    public static int getLastWeekdayOfMonth(int year, int month) { 
        Calendar c = Calendar.getInstance(); 
        c.setFirstDayOfWeek(Calendar.SATURDAY); // 星期天为第一天 
        c.set(year, month - 1, getDaysOfMonth(year, month)); 
        return c.get(Calendar.DAY_OF_WEEK); 
    } 
      
    /** 
     * 获得当前日期字符串，格式"yyyy-MM-dd HH:mm:ss" 
     *  
     * @return 
     */ 
    public static String getNow() { 
        Calendar today = Calendar.getInstance(); 
        return dateToString(today.getTime(), FORMAT_ONE); 
    } 
  
    /** 
     * 根据生日获取星座 
     *  
     * @param birth 
     *          YYYY-mm-dd 
     * @return 
     */ 
    public static String getAstro(String birth) { 
        if (!isDate(birth)) { 
            birth = "2000" + birth; 
        } 
        if (!isDate(birth)) { 
            return ""; 
        } 
        int month = Integer.parseInt(birth.substring(birth.indexOf("-") + 1, 
                birth.lastIndexOf("-"))); 
        int day = Integer.parseInt(birth.substring(birth.lastIndexOf("-") + 1)); 
        String s = "魔羯水瓶双鱼牡羊金牛双子巨蟹狮子处女天秤天蝎射手魔羯"; 
        int[] arr = { 20, 19, 21, 21, 21, 22, 23, 23, 23, 23, 22, 22 }; 
        int start = month * 2 - (day < arr[month - 1] ? 2 : 0); 
        return s.substring(start, start + 2) + "座"; 
    } 
  
    /** 
     * 判断日期是否有效,包括闰年的情况 
     *  
     * @param date 
     *          YYYY-mm-dd 
     * @return 
     */ 
    public static boolean isDate(String date) { 
        StringBuffer reg = new StringBuffer("^((\\d{2}(([02468][048])|([13579][26]))-?((((0?"); 
        reg.append("[13578])|(1[02]))-?((0?[1-9])|([1-2][0-9])|(3[01])))"); 
        reg.append("|(((0?[469])|(11))-?((0?[1-9])|([1-2][0-9])|(30)))|"); 
        reg.append("(0?2-?((0?[1-9])|([1-2][0-9])))))|(\\d{2}(([02468][12"); 
        reg.append("35679])|([13579][01345789]))-?((((0?[13578])|(1[02]))"); 
        reg.append("-?((0?[1-9])|([1-2][0-9])|(3[01])))|(((0?[469])|(11))"); 
        reg.append("-?((0?[1-9])|([1-2][0-9])|(30)))|(0?2-?((0?["); 
        reg.append("1-9])|(1[0-9])|(2[0-8]))))))"); 
        Pattern p = Pattern.compile(reg.toString()); 
        return p.matcher(date).matches(); 
    } 
  
    /** 
     * 取得指定日期过 months 月后的日期 (当 months 为负数表示指定月之前); 
     *  
     * @param date 
     *          日期 为null时表示当天 
     * @param month 
     *          相加(相减)的月数 
     */ 
    public static Date nextMonth(Date date, int months) { 
        Calendar cal = Calendar.getInstance(); 
        if (date != null) { 
            cal.setTime(date); 
        } 
        cal.add(Calendar.MONTH, months); 
        return cal.getTime(); 
    } 
  
    /** 
     * 取得指定日期过 day 天后的日期 (当 day 为负数表示指日期之前); 
     *  
     * @param date 
     *          日期 为null时表示当天 
     * @param month 
     *          相加(相减)的月数 
     */ 
    public static Date nextDay(Date date, int day) { 
        Calendar cal = Calendar.getInstance(); 
        if (date != null) { 
            cal.setTime(date); 
        } 
        cal.add(Calendar.DAY_OF_YEAR, day); 
        return cal.getTime(); 
    } 
  
    /** 
     * 取得距离今天 day 日的日期 
     * @param day 
     * @param format 
     * @return 
     * @author chenyz 
     */ 
    public static String nextDay(int day, String format) { 
        Calendar cal = Calendar.getInstance(); 
        cal.setTime(new Date()); 
        cal.add(Calendar.DAY_OF_YEAR, day); 
        return dateToString(cal.getTime(), format); 
    } 
  
    /** 
     * 取得指定日期过 day 周后的日期 (当 day 为负数表示指定月之前) 
     *  
     * @param date 
     *          日期 为null时表示当天 
     */ 
    public static Date nextWeek(Date date, int week) { 
        Calendar cal = Calendar.getInstance(); 
        if (date != null) { 
            cal.setTime(date); 
        } 
        cal.add(Calendar.WEEK_OF_MONTH, week); 
        return cal.getTime(); 
    } 
  
    /** 
     * 获取当前的日期(yyyy-MM-dd) 
     */ 
    public static String currDay() { 
        return DateUtils.dateToString(new Date(), DateUtils.LONG_DATE_FORMAT); 
    } 
  
    /** 
     * 获取昨天的日期 
     *  
     * @return 
     */ 
    public static String befoDay() { 
        return befoDay(DateUtils.LONG_DATE_FORMAT); 
    } 
  
    /** 
     * 根据时间类型获取昨天的日期 
     * @param format 
     * @return 
     * @author chenyz 
     */ 
    public static String befoDay(String format) { 
        return DateUtils.dateToString(DateUtils.nextDay(new Date(), -1), format); 
    } 
  
    /** 
     * 获取明天的日期 
     */ 
    public static String afterDay() { 
        return DateUtils.dateToString(DateUtils.nextDay(new Date(), 1), 
                DateUtils.LONG_DATE_FORMAT); 
    } 
  
    /** 
     * 取得当前时间距离1900/1/1的天数 
     *  
     * @return 
     */ 
    public static int getDayNum() { 
        int daynum = 0; 
        GregorianCalendar gd = new GregorianCalendar(); 
        Date dt = gd.getTime(); 
        GregorianCalendar gd1 = new GregorianCalendar(1900, 1, 1); 
        Date dt1 = gd1.getTime(); 
        daynum = (int) ((dt.getTime() - dt1.getTime()) / (24 * 60 * 60 * 1000)); 
        return daynum; 
    } 
  
    /** 
     * getDayNum的逆方法(用于处理Excel取出的日期格式数据等) 
     *  
     * @param day 
     * @return 
     */ 
    public static Date getDateByNum(int day) { 
        GregorianCalendar gd = new GregorianCalendar(1900, 1, 1); 
        Date date = gd.getTime(); 
        date = nextDay(date, day); 
        return date; 
    } 
  
    /** 针对yyyy-MM-dd HH:mm:ss格式,显示yyyymmdd */ 
    public static String getYmdDateCN(String datestr) { 
        if (datestr == null) 
            return ""; 
        if (datestr.length() < 10) 
            return ""; 
        StringBuffer buf = new StringBuffer(); 
        buf.append(datestr.substring(0, 4)).append(datestr.substring(5, 7)) 
                .append(datestr.substring(8, 10)); 
        return buf.toString(); 
    } 
  
    /** 
     * 获取本月第一天 
     *  
     * @param format 
     * @return 
     */ 
    public static String getFirstDayOfMonth(String format) { 
        Calendar cal = Calendar.getInstance(); 
        cal.set(Calendar.DATE, 1); 
        return dateToString(cal.getTime(), format); 
    } 
  
    /** 
     * 获取本月最后一天 
     *  
     * @param format 
     * @return 
     */
    public static String getLastDayOfMonth(String format) { 
        Calendar cal = Calendar.getInstance(); 
        cal.set(Calendar.DATE, 1); 
        cal.add(Calendar.MONTH, 1); 
        cal.add(Calendar.DATE, -1); 
        return dateToString(cal.getTime(), format); 
    }    
    
    
    
    
    
    
    
    /**
    * @desc: 获取系统 Timestamp，如（2014-12-18 17:35:46.651）
    * @return Timestamp
     */
    public static Timestamp getCurrentSysTimestamp(){
        Timestamp d = new Timestamp(System.currentTimeMillis());
        return d;
    }
    
    
    
    //----------------------------------------以下是(Long和Date)(Long和yyyy-MM-dd)转换---------------------------------------------------
    
    
    
  
    
    
    /**
     * 获取当前时间的秒数 1970/01/01至今的秒数，,等于new Date().getTime()/1000
     * @param date
     * @return
     * @throws Exception
     */
    public static long getNowTimeStamp()
    {
        long stamp = 0L;
        Date date1 = new Date();
        Date date2 = null;
        try {
            date2 = (new SimpleDateFormat("yyyy/MM/dd HH:mm:ss")).parse("1970/01/01 08:00:00");
        } catch (Exception e) {
            e.printStackTrace();
        }
        stamp = (date1.getTime() - date2.getTime()) / 1000L;
        return stamp;
    }
    
    /**
     * 获取当前时间的毫秒数 1970/01/01至今的毫秒数,等于new Date().getTime()
     * @param date
     * @return
     * @throws Exception
     */
    public static long getNowTimeStampMs(){
         long stamp = 0L;
         Date date1 = new Date();
         Date date2 = null;
         try {
             date2 = (new SimpleDateFormat("yyyy/MM/dd HH:mm:ss")).parse("1970/01/01 08:00:00");
         } catch (Exception e) {
             e.printStackTrace();
         }
         stamp = (date1.getTime() - date2.getTime());
         return stamp;
    }

    
    
    /**
     * 时间转换成秒 1970/01/01至今的秒数（Date转long），等于new Date().getTime()/1000
     * @param date
     * @return
     * @throws Exception
     */
    public static long getTimeStampByDate(Date date) 
    {
        long stamp = 0L;
        Date date1 = date;
        Date date2 = null;
        try {
            date2 = (new SimpleDateFormat("yyyy/MM/dd HH:mm:ss")).parse("1970/01/01 08:00:00");
            stamp = (date1.getTime() - date2.getTime()) / 1000L;
        } catch (Exception e) {
            stamp = 0L;
        }
        
        return stamp;
    }
    
    /**
     * 时间转换成秒 1970/01/01至今的豪秒数（Date转long）
     * @param date
     * @return
     * @throws Exception
     */
    public static long getTimeStampMsByDate(Date date) 
    {
        long stamp = 0L;
        Date date1 = date;
        Date date2 = null;
        try {
            date2 = (new SimpleDateFormat("yyyy/MM/dd HH:mm:ss")).parse("1970/01/01 08:00:00");
            stamp = (date1.getTime() - date2.getTime());
        } catch (Exception e) {
            stamp = 0L;
        }
        
        return stamp;
    }
    
    
    
    
    
    /**
     * 将时间由秒转换成指定格式，如(long转：yyyy-MM-dd HH:mm:ss)
     * @param second
     * @param format
     * @return
     * @throws Exception
     */
    public static String getYYYYByTimeStamp(Long second, String format)
    {
        if(second==null||second==0){
            return "";
        }
        Date da = null;
        try {
            da = (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")).parse("1970-01-01 08:00:00");
        } catch (Exception e) {
            e.printStackTrace();
        }
        Date date = new Date(da.getTime() + second * 1000L);
        return (new SimpleDateFormat(format)).format(date);
    }
    /**
     * 将时间由毫秒转换成指定格式，如(long转：yyyy-MM-dd HH:mm:ss)
     * @param second
     * @param format
     * @return
     * @throws Exception
     */
    public static String getYYYYbyTimeStampMs(Long second, String format)
    {
        if(second==null||second==0){
            return "";
        }
        Date da = null;
        try {
            da = (new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")).parse("1970-01-01 08:00:00");
        } catch (Exception e) {
            e.printStackTrace();
        }
        Date date = new Date(da.getTime() + second );
        return (new SimpleDateFormat(format)).format(date);
    }
    
    
    
    
    /**
     * 1970/01/01至今的秒数转换成Date
     * @param TimeStamp
     * @return
     */
    public static Date getDateByTimeStamp(Long TimeStamp){
        return new Date(TimeStamp*1000);
    }
    
    /**
     * 1970/01/01至今的豪秒数转换成Date
     * @param TimeStampMs
     * @return
     */
    public static Date getDateByTimeStampMs(Long TimeStampMs){
        return new Date(TimeStampMs);
    }    
}