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Java Java Objects (Retired) Delivering the MVP Wrapping up

How do I pass a "User" into the constructor?

I keep getting the error:

./Example.java:10: error: constructor ForumPost in class ForumPost cannot be applied to given types; ForumPost post = new ForumPost("Benyam", "Coding is hard but fun", "Coding takes practice."); ^ required: User,String,String found: String,String,String reason: actual argument String cannot be converted to User by method invocation conversion 1 error

What does it mean to pass a User in? Doesn't the user constructor accept strings? What data type does it want?

public class ForumPost {
  private User mAuthor;
  private String mTitle;
  private String mDescription;

  public ForumPost(User authorName, String title, String description)
   mAuthor = authorName;
   mTitle = title;
   mDescription = description;

  public User getAuthor() {
    return mAuthor;

  public String getTitle() {
    return mTitle;

  public String getDescription()
    return mDescription;

  // TODO: We need to expose the description
public class User {
  private String mFirstName;
    private String mLastName;

   public User(String firstName, String lastName) {
    // TODO:  Set the private fields here
     mFirstName = firstName;
     mLastName = lastName;
 public String getFirstName()
   return mFirstName;

  public String getLastName()
    return mLastName;
public class Forum {
  private String mTopic;

  public Forum(String topicName)
   mTopic = topicName; 

  public String getTopic() {
      return mTopic;

  public void addPost(ForumPost post) {

      System.out.printf("New post from %s %s about %s.\n",

public class Example {

  public static void main(String[] args) {
    System.out.println("Starting forum example...");
    if (args.length < 2) {
       System.out.println("first and last name are required. eg:  java Example Craig Dennis");
    Forum forum = new Forum("Java");
    User author = new User("Benaym", "Ephrem");
    ForumPost post = new ForumPost("Benyam", "Coding is hard but fun", "Coding takes practice.");

1 Answer

Craig Dennis
Craig Dennis
Treehouse Teacher

You need to pass the User that gets created:

User author = new User("Benaym", "Ephrem");

into the forum post.

HINT: Also if you read the instructions carefully, the User should be setup using values from the args array.