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Java Java Objects Delivering the MVP Forum

Jose Villegas
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.a{fill-rule:evenodd;}techdegree
Jose Villegas
Full Stack JavaScript Techdegree Student 8,278 Points

I'm really stuck

I'm stuck on the Main.java this is the error ./Main.java:17: error: constructor ForumPost in class ForumPost cannot be applied to given types; ForumPost post = new ForumPost(author, "Programming is aweson"); ^

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 = topic; 
  }

 public Forum(String topic){
 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 {
  private String firstName;
    private String lastName;
  // TODO: add private fields for firstName and lastName

  public User(String firstName, String lastName) {
    firstName= firstName;
    lastName= lastName;// TODO: set and add the private fields

  }
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; //<--- your code will be different here
    this.title = title; // <---- and here
    this.description = description; //<---- aaand here 

  }

  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
    String firstName = args[0];
    String lastName = args[1];
    User author = new User(firstName, lastName);
    // TODO: initialize the forum post with the user created above and a title and description of your choice
    ForumPost post = new  ForumPost(author, "Programming is aweson");
    forum.addPost(post);

  }

}

1 Answer

james south
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james south
Front End Web Development Techdegree Graduate 33,271 Points

i fixed a few things to get your code to pass. in main you are calling forumPost with an author and a string, but the constructor for forumPost takes an author, a string, and another string, so you need to add an argument there. then, you may need to eliminate the extra space between new and forumPost where you call the constructor. i didn't specifically test that but challenges are picky and it might throw an error on that. anyway, then in user.java, in the User constructor, you need to use the this keyword when setting values, so this.firstName = firstName etc.