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Java Java Objects Delivering the MVP Forum

Shiva Lowy
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.a{fill-rule:evenodd;}techdegree
Shiva Lowy
Full Stack JavaScript Techdegree Student 3,240 Points

I am very confused on where to start with this code

I am very confused on this code. Maybe someone can help me understand 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;
  }


  /* 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 {
  // TODO: add private fields for firstName and lastName

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

  }

  // 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;
  }
}
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();
    // 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

The first step asks you to create a constructor. A constructor is used when creating, in this case, a new ForumPost. Your constructor should be

public ForumPost(String topic) {
    this.topic = topic;
}

this constructor will make it so whenever someone creates a new ForumPost they need to pass in a String topic like so

ForumPost post = new ForumPost("Java");

"Java" is then stored in the variable topic inside the () in the constructor and then you set the private field topic to the topic passed in.