public static void main(String[] args) {
        String[] a = {"1", "2", "3", "4"};
        String[] b = {"2", "3"};
        System.out.println(Arrays.toString(a));
        List<String> aList = Arrays.asList(a);
        List<String> bList = Arrays.asList(b);

        List<String> c = aList.stream().filter(s -> !bList.contains(s)).collect(Collectors.toList());

        System.out.println(c);

    }
}