private NSTimestamp calculateNearestHour() {
        NSTimestamp currentTime = new NSTimestamp();
        TimeZone currentTimeZone = currentTime.timeZone();
        int currentYear = currentTime.yearOfCommonEra();
        int currentMonth = currentTime.monthOfYear();
        int currentDayOfMonth = currentTime.dayOfMonth();  // [1,31]
        int currentHourOfDay = currentTime.hourOfDay();    // [0,23]
        return new NSTimestamp(currentYear, currentMonth, currentDayOfMonth, currentHourOfDay+1, 0, 0, currentTimeZone);