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Java Java Data Structures Exploring the Java Collection Framework Sets

I've added a new class called Blog. It is initialized with a list of BlogPost objects. Create a method in the Blog class

I don't know what am I doing wrong, can someone help?

Kevin Faust
Kevin Faust
15,353 Points

paste your code here

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> set = new TreeSet();
    for (BlogPost authorName : mPosts) {
    return set;

1 Answer

Kevin Faust
Kevin Faust
15,353 Points

import java.util.TreeSet;

You forgot to import TreeSet

Thank you, Kevin. It Worked :)