获取两个日期之间的天数

/**
     * 获取两个日期之间的天数
     * 
     * @param before
     * @param after
     * @return
     */
    public static double getDistanceOfTwoDate(Date before, Date after) {
        long beforeTime = before.getTime();
        long afterTime = after.getTime();
        return (afterTime - beforeTime) / (1000 * 60 * 60 * 24);
    }