【工具】时间工具类

/**
     * @Description 计算某月有多少天
     * @Param [year, month]
     * @return int
     **/
    public static int numOfMonth(int year,int month) {
        int[] intArray={31,28,31,30,31,30,31,31,30,31,30,31};
        if((year % 4 == 0 && year % 100 != 0)||(year % 400 == 0)){
            intArray[1] = 29;//闰年天数加1
        }
        return intArray[month-1];
        //1月的天数对应数组下标为0,所以这里为[month-1]
    }

    /**
     * @Description 计算任意两天相隔天数
     * @Param [date1, date2]
     * @return int
     **/
    public static int differentDays(Date date1, Date date2) {
        Calendar cal1 = Calendar.getInstance();
        cal1.setTime(date1);

        Calendar cal2 = Calendar.getInstance();
        cal2.setTime(date2);
        int day1 = cal1.get(Calendar.DAY_OF_YEAR);
        int day2 = cal2.get(Calendar.DAY_OF_YEAR);

        int year1 = cal1.get(Calendar.YEAR);
        int year2 = cal2.get(Calendar.YEAR);
        if (year1 != year2) // 同一年
        {
            int timeDistance = 0;
            for (int i = year1; i < year2; i++) {
                if (i % 4 == 0 && i % 100 != 0 || i % 400 == 0) {// 闰年
                    timeDistance += 366;
                } else {// 不是闰年
                    timeDistance += 365;
                }
            }
            return timeDistance + (day2 - day1);
        } else {// 不同年
            return day2 - day1;
        }
    }