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Java Java Objects Delivering the MVP Forum

Greg Cruz
Greg Cruz
1,240 Points

Don't understand error in Forum (Java)

So, I went through this and fixed every bug that I possibly could. The final one has me perplexed though.

With the code as it is now, there are zero errors, however the "check work" button now says "Make sure you add a new constructor to the Forum class that accepts a String named topic". I have that. What I had before was "public String topic (String topic) {" for line 6 and the error screen didn't like that. I tried removing the first "String" altogether and it said I needed a return type. So I put void since the constructor shouldn't be returning anything anyway... and now the exercise is telling me to redo what I just was told was an error.

Help please?

Forum.java
public class Forum {
  private String topic;

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

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

  }

  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",
            topic,
            post.getAuthor().getFirstName(),
            post.getAuthor().getLastName(),
            post.getTitle()
    );
  }


}
User.java
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
    this.firstName = firstName;
    this.lastName = lastName;

  }
    public String getFirstName() {
    return firstName;
  }

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

}
ForumPost.java
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) {
    this.author = author;
    this.title = title;
    this.description = description;
  }

  public User getAuthor() {
    return author;
  }

  public String getTitle() {
    return title;
  }

  public String getDescription() {
    return description;
  }
}
Main.java
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");
      System.exit(1);
    }

    Forum forum = new Forum();
    // TODO: pass in the first name and last name that are in the args parameter
    User author = new User(args[0], args[1]);    

    // TODO: initialize the forum post with the user created above and a title and description of your choice
        ForumPost post = new ForumPost(author, "Title here", "Description Here");
    forum.addPost(post);

  }

}

1 Answer

Greg Cruz
Greg Cruz
1,240 Points

Learn from my fail:

" public void topic (String topic) {" but should have been " public Forum (String topic) {"