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Java Java Objects Delivering the MVP Forum

Tojo Alex
Tojo Alex
Courses Plus Student 13,331 Points

Task 4 of 4 should be right

I don't know how but there is an error on line 7 - 8.

public class Forum {
  private String topic;

  // TODO: add a constructor that accepts a topic and sets the private field topic

  public Forum(String topic){
    this.topic = topic.Forum.java();

  public String getTopic() {
    return topic;

  public void addPost(ForumPost post) {
    System.out.printf("A new post in %s topic from %s %s about %s is available",
public class User {
  // TODO: add private fields for firstName and lastName
  private String firstName;
  private String lastName;

  public User(String firstName, String lastName) {
    // TODO: set and add the private fields
    firstName = "";
    lastName = "";

  // TODO: add getters for firstName and lastName
    public String getFirstName(){
    return firstName;

  public String getLastName(){
    return lastName;
public class ForumPost {
  private User author;
  private String title;
  private String description;

  // TODO: add a constructor that accepts the author, title and description
  public ForumPost(User author, String title, String description){
    author = "";
    title = "";
    description = "";

  public User getAuthor() {
    return author;

  public String getTitle() {
    return title;

  public String getDescription() {
    return description;
public class Main {

  public static void main(String[] args) {
   System.out.println("Beginning forum example");
    if (args.length < 2) {
      System.out.println("Usage: java Main <first name> <last name>");
      System.err.println("<first name> and <last name> are required");

    Forum forum = new Forum("Java");
    // TODO: pass in the first name and last name that are in the args parameter

    User author = new User("jyfjfh", "utyfygh"); //<----- all cruicial points marked with comments
    // TODO: initialize the forum post with the user created above and a title and description of your choice

    ForumPost post = new ForumPost(author, "Programming is awesome", "Cuz it makes us create new stuff");



1 Answer

Wikus van der Westhuizen
Wikus van der Westhuizen
Courses Plus Student 4,335 Points

I take it you are referring to this?

public Forum(String topic){
    this.topic = topic.Forum.java();

You are using a a constructor to set a class variable topic. The class variable and the constructor variable is both String objects so you are on the right track. The problem is the "topic.Forum.java()" part.

What you are saying here is that the String object "topic" has a public variable called "Forum" and that this object has a public method called "java".

This is not the case with normal String objects. I think what you meant to write was:

public Forum(String topic){
    this.topic = topic;