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Java Java Data Structures Exploring the Java Collection Framework Sets

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
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()) {
    return authorSet;

1 Answer

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.