java獲取某個月的第一天時間類的相關處理

前言

最近在項目中對時間處理比較細緻,下面就跟大家介紹一下

具體實現方法

 	public static final long ONE_DAY = 24 * 60 * 60 * 1000L;
 
 /**
     * 判斷該日期是否是該月的第一天
     *
     * @param date 需要判斷的日期
     * @return
     */
    public static boolean isFirstDayOfMonth(Date date) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        return calendar.get(Calendar.DAY_OF_MONTH) == 1;
    }

    /**
     * 獲取當月第一天
     *
     * @return
     */
    public static Date getMonthFirstDay(Date date, int day) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        calendar.set(Calendar.DAY_OF_MONTH, 1);//獲取當月第一天
        calendar.add(Calendar.MONTH, day);//day: 0是指本月,-1是向前推一個月,1是向後推一個月
        return calendar.getTime();
    }

    /**
     * 獲取某年第一天日期
     *
     * @param year 年份
     * @return Date
     */
    public static Date getYearFirst(int year) {
        Calendar calendar = Calendar.getInstance();
        calendar.clear();
        calendar.set(Calendar.YEAR, year);
        Date currYearFirst = calendar.getTime();
        return currYearFirst;
    }

    /**
     * 獲取當前年份
     *
     * @param date
     * @return
     */
    public static Integer getYear(Date date) {
        return (date == null) ? 0 : Integer.parseInt(dateToString(date, "yyyy"));
    }
    
 	public static Integer getMonth(Date date) {
        return (date == null) ? 0 : Integer.parseInt(dateToString(date, "MM"));
    }

 /**
     * 將時間轉換爲時間戳
     *
     * @param s
     * @return
     */
    public static String dateToStamp(String s) {
        String res;
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = null;
        try {
            date = simpleDateFormat.parse(s);
        } catch (ParseException e) {
            e.printStackTrace();
        }
        long ts = (date != null ? date.getTime() : 0) / 1000;
        res = String.valueOf(ts);
        return res;
    }

 /**
     * 時間戳轉換成日期格式字符串
     *
     * @param seconds 精確到秒的字符串
     * @param
     * @return
     */
    public static String timeStamp2Date(String seconds, String format) {
        if (seconds == null || seconds.isEmpty() || seconds.equals("null")) {
            return "";
        }
        if (format == null || format.isEmpty()) {
            format = "yyyy-MM-dd HH:mm:ss";
        }
        SimpleDateFormat sdf = new SimpleDateFormat(format);
        return sdf.format(new Date(Long.valueOf(seconds + "000")));
    }

  /**
     * 獲取提前或延後的日期，格式爲yyyy-MM-dd HH:mm
     *
     * @param dateStr
     * @param hour
     * @return
     */
    public static String getDate(String dateStr, int hour) {
        try {
            SimpleDateFormat format = new SimpleDateFormat(DateExtendUtil.FULL);
            java.util.Date date = format.parse(dateStr);
            Calendar cal = Calendar.getInstance();
            cal.setTime(date);
            cal.add(Calendar.HOUR_OF_DAY, hour);
            return format.format(cal.getTime());
        } catch (Exception e) {
            return "";
        }
    }


/****** 用戶會員過期  **********************************/
	 //是否已過期
    public boolean isExpired(Date vipUntil) {
        return vipUntil == null || System.currentTimeMillis() >= vipUntil.getTime();
    }

    //是否已過期
    public boolean isExpired() {
        Date vipUntil = getVipUntil();
        return vipUntil == null || System.currentTimeMillis() >= vipUntil.getTime();
    }

    public Date getVipUntil() {
        Integer companyId = PrincipalAware.getCompanyId();
        if (companyId == null) {
            throw new ResException("用戶未登錄");
        }
        Company company = companyRepository.findOne(companyId);
        if (company == null) {
            throw new ResException("登錄數據已過期,請重新登錄");
        }
        return company.getVipUntil();
    }

	  //是否即將到期了
    public Map<String, Object> isToExpire() {
        Date vipUntil = getVipUntil();
        Map<String, Object> map = new HashMap<>();
        Boolean flag = false;
        Integer days = 0;
        if (vipUntil != null) {
            long begin = DateExtendUtil.dateBackOrInto(vipUntil, -AuthProperties.WARNING_DAYS).getTime();
            long end = vipUntil.getTime();
            long now = System.currentTimeMillis();
            flag = begin <= now && now < end;//處於2周內

            Date expireDay = DateExtendUtil.dateToDate(vipUntil, DateExtendUtil.YEAR);
            Date nowDay = DateExtendUtil.dateToDate(new Date(), DateExtendUtil.YEAR);
            days = Math.toIntExact((expireDay.getTime() - nowDay.getTime()) / DateExtendUtil.ONE_DAY);
        }
        map.put("flag", flag);
        map.put("days", days);
        return map;
    }

    //是否已過期
    public boolean isExpired() {
        return isExpired();
    }