Odczyt słów z pliku

  public SortedWordsFromFile(File file) throws IOException {
        sortedWords = new ArrayList<>();
        try {
            FileReader in = new FileReader(file);
            BufferedReader br = new BufferedReader(in);
            String line = br.readLine();
            while (line != null) {
                sortedWords.add(line);
                line = br.readLine();
            }
            Collections.sort(sortedWords);
            br.close();
           //tutaj próbowałem metody .split (" ") i wyskakiwał NullPointerException
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }

        List<String> data = Files.lines(Paths.get("input.txt"))
                .map(x -> x.split(" "))
                .flatMap(Arrays::stream)
                .collect(Collectors.toList());
        Collections.sort(data);