현재 시각 가져오기

    NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
    
    NSDate *date = [NSDate date];
    NSDateComponents *hourDate = [gregorian components:kCFCalendarUnitHour fromDate:date];
    NSDateComponents *minuteDate = [gregorian components:kCFCalendarUnitMinute fromDate:date];
    NSDateComponents *secondDate = [gregorian components:kCFCalendarUnitSecond fromDate:date];

    int hour = [hourDate hour];
    int minute = [minuteDate minute];
    int second = [secondDate second];