How to convert List to Map with indexes using stream - Java 8?

Question

I\'ve created method whih numerating each character of alphabet. I\'m learning streams(functional programming) and try to use them as often as possible, but I don\'t know ho

Answer 1

Using streams with AtomicInteger in Java 8:

private Map numerateAlphabet(List alphabet) {
    AtomicInteger index = new AtomicInteger();
    return alphabet.stream().collect(
            Collectors.toMap(s -> s, s -> index.getAndIncrement(), (oldV, newV)->newV));
}