private List<String> filterSingleLine(String station1, String station2,
            List<String> line) {
        int station1Index = line.indexOf(station1);
        int station2Index = line.indexOf(station2);
        if (station2Index > -1 && station1Index > -1) {
            if (station1Index > station2Index) {
                List<String> reversedList = line.subList(station2Index,
                        station1Index + 1);
                Collections.reverse(reversedList);
                return new ArrayList<String>(reversedList);
            }
            return new ArrayList<String>(line.subList(station1Index,
                    station2Index + 1));
        }
        return null;
    }