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Java Java Objects Delivering the MVP Forum

gajendran ratnam
gajendran ratnam
2,028 Points

initialize the forum post with the user created above and a title and description of your choice

.

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;
}

  // Uncomment this when you are prompted to do so
  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 {
  private String firstName;
  private String lastName;
  // TODO: add private fields for firstName and lastName

  public User(String firstName, String lastName) {
    // TODO: set and add the private fields
    this.firstName=firstName;
    this.firstName=lastName;
  }
public String getFirstName(){
  return this.firstName;
}
public String getLastName(){
  return this.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 User getAuthor() {
    return author;
  }

  public String getTitle() {
    return title;
  }

  public String getDescription() {
    return description;
  }
  public ForumPost(User author, String title, String description){
    this.author=author;
    this.title=title;
    this.description=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);
    }
    // Uncomment this when prompted
    Forum forum = new Forum("Java");
    // TODO: pass in the first name and last name that are in the args parameter
    User author = new User(args[1], args[2]);
    // TODO: initialize the forum post with the user created above and a title and description of your choice
    ForumPost post = new ForumPost(author.getFirstName,"Java", "Practice");
    forum.addPost(post);

  }

}

1 Answer

Brendan Whiting
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Brendan Whiting
Front End Web Development Techdegree Graduate 84,738 Points

Three things:

1) User.java line 9:

this.firstName=lastName;

It passed that step of the challenge at the time, but you’re assigning the last name to the first name which is causing problems later.

2) Main.java line 13:

User author = new User(args[1], args[2]);

Arrays in Java are 0-based, so it should be args[0], args[1].

3) Main.java line 15:

ForumPost post = new ForumPost(author.getFirstName,"Java", "Practice");

The first parameter of the ForumPost constructor is a User object, so author by itself, not its first name. (And as a side note, if you did want to pass it the first name, you should call the function, as in author.getFirstName(), instead of just putting the name of the function).