How to generate random array of ints using Stream API Java 8?

If you want primitive int values, do not call IntStream::boxed as that produces Integer objects by boxing.

Simply use Random::ints which returns an IntStream:

int[] array = new Random().ints(size, lowBound, highBound).toArray();

To generate random numbers from range 0 to 350, limiting the result to 10, and collect as a List. Later it could be typecasted.

However, There are no guarantees on the type, mutability, serializability, or thread-safety of the List returned.

List<Object> numbers =  new Random().ints(0,350).limit(10).boxed().collect(Collectors.toList());

and to get thearray of int use

int[] numbers =  new Random().ints(0,350).limit(10).toArray();