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Start your free trialGonzalo Nunez
Courses Plus Student 5,064 PointsMSG: Did you not uncomment the Forum.addPost method? It appears to not being called properly in Forum.java.
Iยดm getting this message but this method is uncommented, as you can see in the code
public class ForumPost {
private User mAuthor;
private String mTitle;
private String mDescription;
public User getAuthor() {
return mAuthor;
}
public String getTitle() {
return mTitle;
}
public String getDescription() {
return mDescription;
}
public ForumPost(User author, String title, String description){
}
}
public class User {
private String mFirstName;
private String mLastName;
public User(String firstName, String lastName) {
mFirstName = firstName;
mLastName = lastName;
}
public void setFirstName(String firstName) {
mFirstName = firstName;
}
public void setLastName(String lastName) {
mLastName = lastName;
}
public String getFirstName() {
return mFirstName;
}
public String getLastName() {
return mLastName;
}
}
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.\n",
post.getAuthor().getFirstName(),
post.getAuthor().getLastName(),
post.getTitle());
*/
}
public Forum(String topic){
mTopic = topic;
}
}
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(args[0], args[1]);
// Add the author, title and description
ForumPost post = new ForumPost(author, "Rafael", "Awesome" );
forum.addPost(post);
}
}
4 Answers
anil rahman
7,786 PointsTry uncommenting that code within the method.
Gonzalo Nunez
Courses Plus Student 5,064 PointsWhen I uncomment this part, give this error:
Starting forum example... java.lang.NullPointerException at Forum.addPost(Forum.java:12) at Example.main(Example.java:13) at JavaTester.run(JavaTester.java:183) at JavaTester.main(JavaTester.java:43)
anil rahman
7,786 PointsTry this:
public ForumPost(User author, String title, String description){
//add these in the constructor to actually make sure your variables are being stored
author = mAuthor;
title = mTitle;
description = mDescription;
}
Gonzalo Nunez
Courses Plus Student 5,064 PointsStill getting the same error: NullPointerException
Gonzalo Nunez
Courses Plus Student 5,064 PointsSolved with : public ForumPost(User author, String title, String description){ mAuthor = author; mTitle = title; mDescription = description;
anil rahman
7,786 Pointsanil rahman
7,786 PointsGonzalo Nunez
Courses Plus Student 5,064 PointsGonzalo Nunez
Courses Plus Student 5,064 PointsGive this error: Starting forum example... java.lang.NullPointerException at Forum.addPost(Forum.java:12) at Example.main(Example.java:13) at JavaTester.run(JavaTester.java:183) at JavaTester.main(JavaTester.java:43)
I have tried to reset the code, paste the correct answer that someone posted before... no one works