两个时间相差距离多少天多少小时多少分多少秒

/**
 * 两个时间相差距离多少天多少小时多少分多少秒
 *
 * @param str1
 *            时间参数 1 格式：1990-01-01 12:00:00
 * @param str2
 *            时间参数 2 格式：2009-01-01 12:00:00
 * @return
 * @throw
    long sec = 0;
    try {
        long time1 = str1.getTime();
        long time2 = str2.getTime();
        long diff;
        if (time1 < time2) {
            diff = time2 - time1;
            day = diff / (24 * 60 * 60 * 1000);
            sbu.append(day+"天");
            hour = (diff / (60 * 60 * 1000) - day * 24);
            sbu.append(hour+"时");
            min = ((diff / (60 * 1000)) - day * 24 * 60 - hour * 60);
            sbu.append(min+"分");
            sec = (diff / 1000 - day * 24 * 60 * 60 - hour * 60 * 60 - min * 60);
            sbu.append(sec+"秒");
        }

    } catch (ParseException e) {
        e.printStackTrace();
    }
    return sbu;
}