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Java Java Data Structures - Retired Exploring the Java Collection Framework Sets

Pranjal Agnihotri
Pranjal Agnihotri
4,187 Points
Posted by Pranjal Agnihotri
Pranjal Agnihotri
4,187 Points

The Quiz of topic "Set" questions: (Java Track)

Help me to solve the objective of Set question. Where in BlogClass I have to do the Task.I tried many times it shows java.lang.InvocationTargetException.

Rami Shublaq
Rami Shublaq
3,387 Points
Rami Shublaq
Rami Shublaq
3,387 Points 
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() {
    Set<String> authorSet = new TreeSet<String>();
    for(BlogPost post : getPosts()) {
      authorSet.add(post.getAuthor());
    }
    return authorSet;
  }
}

1 Answer

John Paige
John Paige
7,436 Points
John Paige
John Paige
7,436 Points

Hey Pranjal. What you'll do is place the method in the Blog class, and also import the needed Sets for that class too.