问如何找出两个Joda-Time DateTimes在分钟内的差异

EN

public List<Map<String, Object>> loadNotYetInEmployee(int shift, Date date,
        int transitionVal, String type, User user) {

    DateTime datetime = new DateTime(date);
    datetime = datetime
            .plus(Period.minutes(shiftTiming.getSession1InTime()));

    List<Map<String, Object>> result = new ArrayList<Map<String, Object>>();

    sql = SqlMapUtils.getSql("attendance.attendancestatus.latein",
            parameters);
    result = getJdbcTemplate().queryForList(sql);
    for (int i = 0; i < result.size(); i++) {
        Date punchInTime = (Date) result.get(i).get("punchtime");
        DateTime punchTime = new DateTime(punchInTime);
    }
    return result;
}