Java: Interleave two integer based arraylists -> good approach?

Question

Homework: Looking for better strategy, or approach rather than complete code.

I\'v got two arrayLists of integers under two conditions:

1. th

Answer 1

I propose the following code:

private static List joinTwoLists(List a, List b) {
    final boolean aIsBigger = a.size() > b.size();
    final List joined = new ArrayList<>(aIsBigger ? a : b);
    final AtomicInteger index = new AtomicInteger(1);
    for (Integer value : aIsBigger ? b : a) {
        joined.add(index.getAndAdd(2), value);
    }
    return joined;
}