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Start your free trialDax Stucki
1,034 Pointsthe User author element reeeally giving me trouble at the end of this challenge
I'm so close to wrapping up this challenge but I get a "nullPointerException" error. I don't know how to remedy this. It's the last part, I think I have it right, I'm not sure how I've messed up.
Any help would be appreciated.
thank you
public class ForumPost {
private User mAuthor;
private String mTitle;
private String mDescription;
public ForumPost(User author, String title, String description)
{
User mAuthor = author;
mTitle = title;
mDescription = description;
}
public String getDescription()
{
return mDescription;
}
public User getAuthor() {
return mAuthor;
}
public String getTitle() {
return mTitle;
}
// TODO: We need to expose the description
}
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;
}
}
public class Forum {
private String mTopic;
public Forum(String topic)
{
mTopic = topic;
}
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());
}
}
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("Dax", "Stucki");
// Add the author, title and description
ForumPost post = new ForumPost(author, "Done", "Woo Hoo");
forum.addPost(post);
}
}
1 Answer
Grigorij Schleifer
10,365 PointsHi Dax,
you should use the command line arguments for the creation of the User object like this:
User author = new User(args[0], args[1]);
So the compiler takes this arguments for the creation of the User object.
Grigorij