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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

task 4 main

keep throwing this error Are you sure you used the arguments passed in from the main method in Main.java? args[0] is the firstName and args[1] should be the last name

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) {
    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) {
    // TODO: set and add the private fields
    firstName= firstName;
    lastName= lastName;

  }
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;
    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);
    }

    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, "Java" , "Programming from scrathc");
    forum.addPost(post);

  }

}

1 Answer

andren
andren
28,558 Points

The issue is the constructor you have written for the Forum and User class. You have forgotten to include the this keyword that is needed since the field variables and parameters passed in shares the same name. You have done it correctly for the ForumPost constructor so you can look at that for an example of how the constructor should look.