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Java Java Objects (Retired) Delivering the MVP Wrapping up

How do I pass a "User" into the constructor?

I keep getting the error:


./Example.java:10: error: constructor ForumPost in class ForumPost cannot be applied to given types; ForumPost post = new ForumPost("Benyam", "Coding is hard but fun", "Coding takes practice."); ^ required: User,String,String found: String,String,String reason: actual argument String cannot be converted to User by method invocation conversion 1 error


What does it mean to pass a User in? Doesn't the user constructor accept strings? What data type does it want?

ForumPost.java
public class ForumPost {
  private User mAuthor;
  private String mTitle;
  private String mDescription;

  public ForumPost(User authorName, String title, String description)
  {
   mAuthor = authorName;
   mTitle = title;
   mDescription = description;
  }

  public User getAuthor() {
    return mAuthor;
  }

  public String getTitle() {
    return mTitle;
  }

  public String getDescription()
  {
    return mDescription;
  }

  // TODO: We need to expose the description
}
User.java
public class User {
  private String mFirstName;
    private String mLastName;

   public User(String firstName, String lastName) {
    // TODO:  Set the private fields here
     mFirstName = firstName;
     mLastName = lastName;
      }
 public String getFirstName()
 {
   return mFirstName;
 }

  public String getLastName()
  {
    return mLastName;
  }
}
Forum.java
public class Forum {
  private String mTopic;

  public Forum(String topicName)
  {
   mTopic = topicName; 
  }

  public String getTopic() {
      return mTopic;
  }

  public void addPost(ForumPost post) {

      System.out.printf("New post from %s %s about %s.\n",
                         post.getAuthor().getFirstName(),
                         post.getAuthor().getLastName(),
                         post.getTitle());

  }
}
Example.java
public class Example {

  public static void main(String[] args) {
    System.out.println("Starting forum example...");
    if (args.length < 2) {
       System.out.println("first and last name are required. eg:  java Example Craig Dennis");
    }
    Forum forum = new Forum("Java");
    User author = new User("Benaym", "Ephrem");
    ForumPost post = new ForumPost("Benyam", "Coding is hard but fun", "Coding takes practice.");
    forum.addPost(post);
  }
}

1 Answer

Craig Dennis
STAFF
Craig Dennis
Treehouse Teacher

You need to pass the User that gets created:

User author = new User("Benaym", "Ephrem");

into the forum post.

HINT: Also if you read the instructions carefully, the User should be setup using values from the args array.