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Java Java Objects Delivering the MVP Forum

what is wrong with passing the first name and last name that way ? User author = new User(args[0],args[1]);

It says there is something wrong in passing the first name and last name from the args main method

Forum.java
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 ;
  }
  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
    firstName = "";
    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;
    title = "";
    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("Java");
    // 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,"treehouse","online course");
    forum.addPost(post);
  }

}

1 Answer

Your Constructor in the User class does not initialize the fields. Instead it just sets the parameters to an empty string. You do the same thing with title and description in the ForumPost Constructor. Initialize your variables correctly and it should work just fine!