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Sara Pasinato
1,023 PointsHow return a Set<String>list ??
The error displayed "Expected 5 authors, but received 0"
package com.example;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
public class BlogPost implements Comparable<BlogPost>, Serializable {
private String mAuthor;
private String mTitle;
private String mBody;
private String mCategory;
private Date mCreationDate;
public BlogPost(String author, String title, String body, String category, Date creationDate) {
mAuthor = author;
mTitle = title;
mBody = body;
mCategory = category;
mCreationDate = creationDate;
}
public int compareTo(BlogPost other) {
if (equals(other)) {
return 0;
}
return mCreationDate.compareTo(other.mCreationDate);
}
public String[] getWords() {
return mBody.split("\\s+");
}
public List<String> getExternalLinks() {
List<String> links = new ArrayList<String>();
for (String word : getWords()) {
if (word.startsWith("http")) {
links.add(word);
}
}
return links;
}
public String getAuthor() {
return mAuthor;
}
public String getTitle() {
return mTitle;
}
public String getBody() {
return mBody;
}
public String getCategory() {
return mCategory;
}
public Date getCreationDate() {
return mCreationDate;
}
}
package com.example;
import java.util.List;
import java.util.Arrays;
import java.util.Set;
import java.util.*;
public class Blog {
List<BlogPost> mPosts;
Set<String> allAuthor = new TreeSet<String>();
public Set<String> getAllAuthors(){
for (BlogPost post : mPosts) {
allAuthor.addAll(post.getExternalLinks());
}
return allAuthor;
}
public Blog(List<BlogPost> posts) {
mPosts = posts;
}
public List<BlogPost> getPosts() {
return mPosts;
}
}
2 Answers

Jacob Ludwig
2,065 PointsGreat Job!

Sara Pasinato
1,023 PointsYes, I have change it with getAthor() :) Like this:
public Set<String> getAllAuthors() {
Set<String> authors = new TreeSet<>();
for (BlogPost post: mPosts) {
authors.add(post.getAuthor());
}
return authors;}
and I've done:)
Jacob Ludwig
2,065 PointsJacob Ludwig
2,065 PointsWhy did you choose "getExternalLinks()"? Is there another getter that might be more appropriate? :)