Java Java Objects Delivering the MVP Forum

I need help with this problem.

I am just not getting it.

Forum.java
public class Forum {
  private String topic;

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

  public String getTopic() {
    return topic;
  }

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

  }

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

  public String getLastName() {
    return 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();
    // TODO: initialize the forum post with the user created above and a title and description of your choice
    ForumPost post = new ForumPost();
    forum.addPost(post);


  }

}

1 Answer

Steven Parker
Steven Parker
177,847 Points

You're really close! In the earlier tasks you changed the signatures of the "User" and "ForumPost" classes, so now you need to fix the revealed code so it uses the new constructors correctly:

    // TODO: pass in the first name and last name that are in the args parameter
    User author = new User();

The new "User" constructor requires two strings to be passed in. The "TODO" tells you to use two of the items from the command "args" array.

    // TODO: initialize the forum post with the user created above and a title and description of your choice
    ForumPost post = new ForumPost();

The new constructor for "ForumPost" takes a User and two string arguments. The User is the one created just a couple of lines earlier, and you can make up any strings you like for the other two arguments.