Turn a stream of objects into a linked list of attributes

java, java-8, java-stream, lambda

Solution

You can use a `Collector` like this to put the result into a `LinkedList`:

LinkedList<String> usernames2 = users.stream()
                                .map(User::getUsername)
                                .collect(Collectors.toCollection(LinkedList::new));

Problem

My goal: Take a `LinkedList` of `User`s and extract a `LinkedList` of their usernames in an elegant, Java-8 way. ``` public static void main(String[] args) { LinkedList<User> users = new LinkedList<>(); users.add(new User(1, "User1")); users.add(new User(2, "User2")); users.add(new User(3, "User3")); // Vanilla Java approach LinkedList<String> usernames = new LinkedList<>(); for(User user : users) { System.out.println(user.getUsername()); usernames.add(user.getUsername()); } System.out.println("Usernames = " + usernames.toString()); // Java 8 approach users.forEach((user) -> System.out.println(user.getUsername())); LinkedList<String> usernames2 = users.stream().map(User::getUsername). // Is there a way to turn this map into a LinkedList? System.out.println("Usernames = " + usernames2.toString()); } static class User { int id; String username; public User() { } public User(int id, String username) { this.id = id; this.username = username; } public void setUsername(String username) { this.username = username; } public void setId(int id) { this.id = id; } public String getUsername() { return username; } public int getId() { return id; } } ``` I am stuck trying to convert the `Stream` object into a `LinkedList`. I could turn it into an array (`Stream::toArray()`) and turn that into a `List` (`Arrays.asList(Stream::toArray())`) but that just seems so... no thank you. Am I missing something?

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