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Start your free trialJay Bhatt
6,502 PointsHow do I retrieve the authors (using getAuthors()) from the original BlogPost class into the Blog class?
I am having trouble using the getAuthors() to get the authors. Please help
package com.example;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;
import java.util.HashSet;
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.Set;
import java.util.TreeSet;
import java.util.HashSet;
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> authors = new TreeSet<String> ();
BlogPost
for (BlogPost post: mPosts[0]) {
authors.addAll(post.getAuthor());
}
return authors;
}
}
1 Answer
Alexander Nikiforov
Java Web Development Techdegree Graduate 22,175 PointsYou are almost there. Here is hint sudo code:
public Set<String> getAllAuthors() {
// this is correct : initialized new TreeSet
Set<String> authors = new TreeSet<String> ();
// BlogPost wrong
// Cycle through ALL mPosts,
// not through mPosts[0], which is only one Post at index 0
// for (BlogPost post: mPosts[0]) { // FIX HERE and uncomment
// Hint: use `add` method not `addAll`, because you are inside loop
// you are looping for each post
// and for each post you add one author
// authors.addAll(post.getAuthor()); // FIX HERE and uncomment
//}
// that is correct line
return authors;
}
Jay Bhatt
6,502 PointsJay Bhatt
6,502 PointsIt worked. Thank you. I don't why I did addAll or mPost[0].