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Start your free trialTimothy Williams
1,536 Pointsmy getAllAuthors is failing to compile
I'm not fully grasping Sets, Lists, etc pffft! Help
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> getAllAuthors() {
Set<String> allAuthors = new TreeSet<String>();
for (BlogPost blogpost:mPosts){
allAuthors.addAll(blogpost.getAuthor());
}
return allAuthors;
}
public List<BlogPost> getPosts() {
return mPosts;
}
}
1 Answer
Dan Johnson
40,533 PointsThe addAll method is for adding an entire collection (anything implementing this interface) to the Set. You can use add for single items.
Other than that you just need to change your return value to the appropriate type.
Rulon Taylor
2,762 PointsRulon Taylor
2,762 PointsThanks for this response. It was what I needed to get going!