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Java Java Objects (Retired) Delivering the MVP Wrapping up

Nickolas Ramos
Nickolas Ramos
5,442 Points

Help! I need assistance with "Bummer! java.lang.NullPointerException (Look around Forum.java line 14)"

I've looked around the forum to see if anyone else is having this problem, but I can't find anything! Does anyone have any suggestions about what's going on?

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

  public ForumPost(User Author, String Title, String 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 String getTopic() {
      return mTopic;

   Forum (String topic) {
     mTopic = topic;

  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(args[0], args[1]);
    ForumPost post = new ForumPost(author,"This Challenge" ,"Was awesome");

2 Answers

Nickolas Ramos
Nickolas Ramos
5,442 Points

I solved it! I didn't realize that the constructor in forumPost.java didn't have member variables declared in the constructor.

you should copy the question if you need help in most cases not the error