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Java Java Objects Delivering the MVP Forum

Tojo Alex
PLUS
Tojo Alex
Courses Plus Student 13,331 Points

Challenge Task 4 of 4

This is the 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. All help appreciated.?

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;
    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

    User author = new User("jyfjfh", "utyfygh"); //<----- all cruicial points marked with comments
    // 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 awesome", "Cuz it makes us create new stuff");
    forum.addPost(post);
  }

}

6 Answers

Brendon Butler
Brendon Butler
4,254 Points

When creating a new user, you have to take the arguments from the main method and input them here

User author = new User(args[0], args[1]);
Tojo Alex
PLUS
Tojo Alex
Courses Plus Student 13,331 Points

./Main.java:16: error: variable author is already defined in method main(String[]) User author = new User(args[0], args[1]); ^ Note: JavaTester.java uses unchecked or unsafe operations. Note: Recompile with -Xlint:unchecked for details. 1 error

After I add that.

Brendon Butler
Brendon Butler
4,254 Points

Did you remove this line?

User author = new User("jyfjfh", "utyfygh");
Tojo Alex
PLUS
Tojo Alex
Courses Plus Student 13,331 Points

Though it takes me to the begging 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

Brendon Butler
Brendon Butler
4,254 Points

Did you keep the line I provided?