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Java Java Data Structures Exploring the Java Collection Framework Sets

Derek Derek
Derek Derek
8,744 Points
Posted by Derek Derek
Derek Derek
8,744 Points

Compile time error

Can someone please help me pass this task? Also, should I declare the return type of the method getAllAuthors as Set<String> or TreeSet<String> ? Thank you in advance!

1 Answer

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

Hi there,

Make sure you include the correct import statements first.

Then, create the method that returns a Set and takes no parameters. Inside, create the set to be returned; use a TreeSet for ordering. Then iterate over all posts in mPosts using a for loop adding the individual post's author to the set using add and the post's getAuthor method. Then return your Set.

It'll look like this:

  public Set<String> getAllAuthors(){
    Set<String> allAuthors = new TreeSet<String>(); // create the set
    for (BlogPost post : mPosts){    // iterate over all posts one at a time
      allAuthors.add(post.getAuthor());    // get each post's author and add to set
    }
    return allAuthors; // return the set
  }

I hope that helps,

Steve.