public static Map<TimeUnit, Long> computeDifference(Calendar date1, Calendar date2) {

    long diffInMillies = date2.getTimeInMillis() - date1.getTimeInMillis();

    //create the list
    List<TimeUnit> units = new ArrayList<TimeUnit>();
    units.add(TimeUnit.SECONDS);
    units.add(TimeUnit.MINUTES);
    units.add(TimeUnit.HOURS);
    units.add(TimeUnit.DAYS);
    Collections.reverse(units);

    //create the result map of TimeUnit and difference
    Map<TimeUnit,Long> result = new LinkedHashMap<TimeUnit,Long>();
    long milliesRest = diffInMillies;

    for ( TimeUnit unit : units ) {

        //calculate difference in millisecond
        long diff = unit.convert(milliesRest,TimeUnit.MILLISECONDS);
        long diffInMilliesForUnit = unit.toMillis(diff);
        milliesRest = milliesRest - diffInMilliesForUnit;

        //put the result in the map
        result.put(unit,diff);
    }

    return result;
}