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Java Java Objects Delivering the MVP Forum

Jordan Bartholomew
Jordan Bartholomew
5,926 Points
Posted by Jordan Bartholomew
Jordan Bartholomew
5,926 Points

Java Objects Constructor

I can't figure out any of these challenges. Can someone help me finish this? Thanks

Challenge Task 1 of 4

Can I please borrow your object powers to help me finish out this Forum prototype I've been working on? We'll go through a couple of steps here, like always, just follow the prompts for each step. Let's do this!

Add a constructor that accepts a String named topic to Forum.java. Initialize the private field topic in the constructor to the value passed in.

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);

// */
  }

}
Marcus Yow
Marcus Yow
12,929 Points
Marcus Yow
Marcus Yow
12,929 Points

Below I've posted answers to the challenge.

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;
  }


  // 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
  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);
    }
    //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[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,"title","description");
    forum.addPost(post);

  }

}
Chris Tvedt
Chris Tvedt
3,795 Points
Chris Tvedt
Chris Tvedt
3,795 Points

Marcus that is not helpful. You should explain his mistakes or at least thoroughly comment your code so he can read it and learn from it. He learns little by just copying and pasting your code.