Java: making List from primitive array using Stream API

Question

I\'m trying to make a List from a primitive array

int[] values={4,5,2,3,42,60,20};
List greaterThan4 =
Arrays.stream(values)
        .filter(v         


        

Answer 1

Yes this is because Arrays.stream returns an IntStream. You can call boxed() to get a Stream<Integer> and then perform the collect operation.

List<Integer> greaterThan4 = Arrays.stream(values)
                                   .filter(value -> value > 4)
                                   .boxed()
                                   .collect(Collectors.toList());

Answer 2

You can change int[] values={4,5,2,3,42,60,20}; to Integer[] values={4,5,2,3,42,60,20}; because currently you are passing an array of primitive type(int) but should you pass array of object i.e. Integer

Answer 3

You're using an array of primitives for one thing, not Integer. I suggest you use Arrays.asList(T...) like

Integer[] values={4,5,2,3,42,60,20};
List<Integer> al = new ArrayList<>(Arrays.asList(values));