Retrieve all values from HashMap keys in an ArrayList Java

Question

Good day, this is kind of confusing me now(brain freeze!) and seem to be missing something. Have an ArrayList which i populate with a HashMap. now i put in my HashMap and arrayl

Answer 1

Java 8 solution for produce string like "key1: value1,key2: value2"

private static String hashMapToString(HashMap hashMap) {

    return hashMap.keySet().stream()
            .map((key) -> key + ": " + hashMap.get(key))
            .collect(Collectors.joining(","));

}

and produce a list simple collect as list

private static List hashMapToList(HashMap hashMap) {

    return hashMap.keySet().stream()
            .map((key) -> key + ": " + hashMap.get(key))
            .collect(Collectors.toList());

}