hi guys, I have went through this test however I have questions on a few things that dont really make sense to me.

Question

1) why is "author" being accepted in the Main class when i dont even have an instance of it. I just called the forum post constructor in the Main and passed it ("author", topic, description) how does Main.java know what author is, theres nothing that instantiates forumPost post class eg forumPost forum = new ForumPost()

2) how exactly is the args array getting filled, does it ONLY take info you pass into you default constructor, or will it carry on and save almost your entire program in the args array eg variables, printouts, ints that have been turned to strings etc

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
    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 = descriptioin;
  }

  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(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, "args array", "dont grasp this a 100%");
    forum.addPost(post);

   }

}

Answer 1 · 2017-02-12T06:17:45Z

February 12, 2017 6:17am

Hi Thandolwethu,

It might be easier to answer question 2 first since question 1 depends on it.

Question 2 - The args array is a way for you to pass arguments into your program from the command line.

An example usage:

java Main Thandolwethu Bhebhe

This will run the Main class and it will pass those 2 arguments into the Main method as the args array. This means that args[0] is storing your first name and args[1] is storing your last name.

Question 1 -

A User object is created with the following code:

User author = new User(args[0],args[1]);

This creates a User object with whatever first and last name was passed into the program at the command line and stores it in the variable author. This user object can then be passed into the ForumPost constructor to create a ForumPost with that user as the author.

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Thandolwethu Bhebhe

Thandolwethu Bhebhe

hi guys, I have went through this test however I have questions on a few things that dont really make sense to me.

Louis Sankey

Louis Sankey

1 Answer

Jason Anello

Jason Anello