Как удалить дубликаты строк из другого файла?

Implemetation using Java Stream API

        String fileFirst = "/home/user/1.txt";//here is your files
        String fileSecond = "/home/user/2.txt";
        String fileResult = "/home/user/1-exclude-2.txt";
        try (Stream<String> streamFirst = Files.lines(Paths.get(fileFirst)); 
                Stream<String> streamSecond = Files.lines(Paths.get(fileSecond))) {
            List<String> list = streamSecond.collect(Collectors.toList());
            List<String> resultList = streamFirst.filter(line -> !list.contains(line)).collect(Collectors.toList());            
            Files.write(Paths.get(fileResult), resultList);
        } catch (IOException e) {
            e.printStackTrace();
        }