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Danijel Buhin
7,460 PointsI've added a new class called Blog. It is initialized with a list of blog posts. Create a method in the Blog class calle
Where is problem ?
When I "Recheck work" they say problem is with "return author";
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<BlogPost> getAllAuthors(){
Set<String> authors = new TreeSet();
for (BlogPost posts:mPosts){
authors.add(posts.getAuthor());
}
return author;
}
}
9 Answers
Shezan Kazi
10,807 PointsOh sorry, I missed the obvious.. It is not Set<BlogPost> but Set<String>.. Try this please:
public Set<String> getAllAuthors() {
Set<String> allAuthors = new TreeSet<String>();
for (BlogPost post : mPosts) {
allAuthors.add(post.getAuthor());
}
return allAuthors;
}
}
Shezan Kazi
10,807 PointsWhere did you define author? Was it in one of the other files? If not, then perhaps should be
return authors;```
With the plural als you created a Set called authors (plural).
Danijel Buhin
7,460 PointsI define author here. And I tried solve this problem with couple ways. I'am really stuck here.
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;
}
}
Shezan Kazi
10,807 Pointsare you sure it is not return authors?
Shezan Kazi
10,807 Pointsor
return mAuthors;
Danijel Buhin
7,460 PointsIts not authors, and mAuthors. example link
Shezan Kazi
10,807 Pointswhich challenge is it? i'll have a look
Danijel Buhin
7,460 PointsJava data structures - sets
Danijel Buhin
7,460 PointsThanks you!
Shezan Kazi
10,807 Pointsglad to help!
Shezan Kazi
10,807 PointsShezan Kazi
10,807 Pointsmy fitst sentence missed a whole lot. You need to specify the return type for the Set, which is not BlogPost but String - since BlogPost is a String.