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Java Java Data Structures - Retired Exploring the Java Collection Framework Sets

Nicklas Millard
Nicklas Millard
9,542 Points
Posted by Nicklas Millard
Nicklas Millard
9,542 Points

What am I doing wrong?

I've attached my code...

  public Set<String> getAllAuthors() {
    Set<String> allAuthors = new TreeSet<String>();
    for (String author : getPosts()) {
      allAuthors.add(author);
    }
    return allAuthors;
  }

[Mod - formatting fix]

1 Answer

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

In your for loop, you're looping over a list of BlogPosts, not Strings. To get the authors, you need to get the author from each post inside the loop.

public Set<String> getAllAuthors() {
   Set<String> allAuthors = new TreeSet<String>();
   for (BlogPost post: getPosts()) {
      allAuthors.add(post.getAuthor());
   }
   return allAuthors;
}