We are currently in the process of building a Forum. There is some skeleton code here, but I need your help to finish it

Question

ammm can anyone help me with this
We are currently in the process of building a Forum. There is some skeleton code here, but I need your help to finish it up. Let's do this! 
In the Forum class, add a constructor that takes a String for the topic and sets the private field mTopic.
```ForumPost.java
public class ForumPost {
  private User mAuthor;
  private String mTitle;
  private String mDescription;
  public User getAuthor() {
    return mAuthor;
  }
  public String getTitle() {
    return mTitle;
  }
  // TODO: We need to expose the description
}
```
```User.java
public class User {
  public User(String firstName, String lastName) {
    // TODO:  Set the private fields here
  }
}
```
```Forum.java
public class Forum {
  private String mTopic;
  public void  setTopic(String topic) {
  mTopic = topic;
  }
  public String getTopic() {
      return mTopic;
  }
  public void addPost(ForumPost post) {
  System.out.printf("New post from %s %s about %s.
",
                     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");
    // Take the first two elements passed args
    // User author = new User();
    // Add the author, title and description
    // ForumPost post = new ForumPost();
    // forum.addPost(post);
  }
}
```

Ken Alger · Accepted Answer

Ahmed;
If you have forgotten about constructors in Java, I would suggest watching the Constructors (https://teamtreehouse.com/library/java-objects/meet-objects/constructors) video again. Mr. Dennis does a nice job of explaining their reasoning for existence and their use. In summary constructors are methods you can use to set initial values for field variables. When the object is created, Java calls the constructor first. Any code you have in your constructor will then get executed. You don't need to make any special calls to a constructor method - they happen automatically when you create a new object.
Constructor methods take the same name as the class, so for this challenge we need to create a method with the same name as our Forum class that takes a String for the topic and sets the private field mTopic. Let's work on syntax first, then add functionality.
We need to create a method with the same name as the class, in this case, Forum, that looks like:
java
Forum() {}

It needs to take a String for the topic...
java
Forum(String topic) {}

Now, we should probably add an access modifier to our constructor. If we do not add an access modifier they default to package private, so outside our package the constructor would not be accessible. That will work for this challenge to leave off the access modifier, but for our purposes at this point in the challenge setting it to public is a good practice. We would then have:
java
public Forum(String topic) {}

Great, now we have our constructor defined, but it isn't doing anything. We were asked to set the private mTopic to the value passed into the method, topic. Inside our function we need to do an assignment of mTopic = topic;
That should do it. I hope that helps explain things a bit, but post back if you are still stuck or if I just confused you even more.
Happy coding,
Ken

Ken Alger · Answer

Ahmed;
A couple of things here. 
I don't see a constructor in your Forum class like is required for the challenge.
It looks like you uncommented the code prior to the end of the challenge, that will cause issues until the remainder of the challenge is completed.
Post back if you are still stuck.
Ken

MUZ140876 Andrew Ndhlangisa · Answer

public class Forum {
  private String mTopic;
  public String getTopic() {
      return mTopic;
  }
  public void addPost(ForumPost post) {
      /* When all is ready uncomment this...
      System.out.printf("New post from %s %s about %s.
",
                         post.getAuthor().getFirstName(),
                         post.getAuthor().getLastName(),
                         post.getTitle());
      */
  }
public Forum(String getTopic) {
    mTopic = getTopic;
  }
}

hubertl · Answer

Hi Ahmed, not sure if this is sorted or yet or not. If not please ensure that you will use class Forum (select the correct file Forum.java).
Constructor needs to look as follow:
(as explained by Ken - where Forum is class name - topic is a string variable and mTopic is already declared private string variable.
 public Forum(String topic)
   {
    mTopic = topic;
  }  
Thanks, Hubert

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ahmed alghafli

ahmed alghafli

We are currently in the process of building a Forum. There is some skeleton code here, but I need your help to finish it

4 Answers

Ken Alger

Ken Alger

ahmed alghafli

ahmed alghafli

MUZ140584 Heredity Mbundire

MUZ140584 Heredity Mbundire

Ken Alger

Ken Alger

ahmed alghafli

ahmed alghafli

hubertl

hubertl

MUZ140876 Andrew Ndhlangisa

MUZ140876 Andrew Ndhlangisa