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Stuck on Sets Challenge Java Data Structures

I cannot figure out what is wrong with my code. Has been frustrating me for the past couple of days. The challenge is as follows:

I've added a new class called Blog. It is initialized with a list of blog posts. Create a method in the Blog class called getAllAuthors that loops all the posts and returns a java.util.Set of all the authors. They should be sorted alphabetically. My code is as follows:

package com.example;

import java.util.List;
import java.util.Set;

public class Blog {
  List<BlogPost> mPosts;

  public Blog(List<BlogPost> posts) {
    mPosts = posts;

  public List<BlogPost> getPosts() {
    return mPosts;

public Set<String> getAllAuthors(){
    Set<String> authors = new TreeSet();
    for (BlogPost posts:mPosts){
    return authors;

2 Answers

Allan Clark
Allan Clark
10,810 Points

Don't forget to import your TreeSet.

I wish I could give you an excuse for this silly mistake by saying that it is a Monday, but sadly, it's Tuesday... :/ aha

Allan Clark
Allan Clark
10,810 Points

haha it happens to the best of us :D

May the Java force be with you