Java 8/9: Can a character in a String be mapped to its indices (using streams)?

Question

Given a String s and a char c, I\'m curious if there exists some method of producing a List list from s (where

Answer 1

Using Java 9, you can iteratively search using the last index as the starting point, and stop when no match is found:

public static List getIndexList(String s, char c) {
    return IntStream.iterate(s.indexOf(c), i -> s.indexOf(c, i + 1))
            .takeWhile(i -> i > -1)
            .boxed()
            .collect(Collectors.toList());
}

Disclaimer: I didn't test this.