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Java Java Data Structures Exploring the Java Collection Framework Sets

Posted by Stephen Kilgore
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Stephen Kilgore
Java Web Development Techdegree Student 2,610 Points

A little help needed

I'm working on this and I feel like I've implemented the solution correctly. No compile errors, but the automated check doesn't seem to be seeing my method. The error I'm getting is "Did you add a method getAllAuthors() to the blog class?

com/example/Blog.java 
package com.example;

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

public class Blog {
  List<BlogPost> mPosts;

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

  public List<BlogPost> getPosts() {
    return mPosts;
  }
  public Set<String> getAllAuthors(List<BlogPost> blogPosts)
  {
    Set<String> authorList = new TreeSet();
    for (BlogPost blogPost : blogPosts)
    {
      authorList.add(blogPost.getAuthor());
    }
    return authorList;
  }
}

1 Answer

Jason Wiram
Jason Wiram
42,762 Points
Jason Wiram
Jason Wiram
42,762 Points

You are very close. You don't need to pass any parameters to the getAllAuthors() method. The Blog class constructor takes 'List<BlogPost> blogPosts' as a parameter and initializes it to the field mPosts. That is the list you will iterate over in your function. Make sense?