Хвосто-рекурсивная версия:
public static void datesBetweenRecursive(Date startDate, Date endDate, List<Date> dates) {
if (startDate.before(endDate)) {
dates.add(startDate);
Calendar calendar = Calendar.getInstance();
calendar.setTime(startDate);
calendar.add(Calendar.DATE, 1);
datesBetweenRecursive(calendar.getTime(), endDate, dates);
}
}