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dlpuxdzztg
8,243 PointsI'm forgetting the proper import statements?
So i'm currently taking the challenge for 'sets'...I imported all that was necessary but it still tells me that I forgot to add the proper import statements.
package com.example;
import java.util.List;
import java.util.Set;
import java.util.HashSet;
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> allPosts = new TreeSet<String>();
for (String word : getPosts()) {
if (word.equals(getAuthor())) {
allPosts.getAuthor(word);
}
}
return allPosts;
}
}
Simon Coates
28,694 PointsJeremy Hill notes a type mismatch. getPost returns a lits of BlogPost, which can't be assigned to the String word. Beyond this, you seem confused.
if (word.equals(getAuthor())) {
with the above, get author is being called, but not on anything. getAuthor is a BlogPost method, hence has to be called on an instance of a blogpost.
allPosts.getAuthor(word);
with the above, allPosts is a set of strings, hence probably doesn't have a getAuthor method.
(The message about import statements seems to be happening because the code finds something it can't understand, and assumes that you forget to import something. I think.)
4 Answers
Jeremy Hill
29,567 PointsI just jumped into the challenge and passed with this code, but don't forget to add imports for Set and TreeSet:
//import these at the top under your package declaration:
//import java.util.Set;
//import java.util.TreeSet;
public Set<String> getAllAuthors(){
Set<String> authors = new TreeSet<String>();
for(BlogPost post : mPosts){
authors.add(post.getAuthor());
}
return authors;
}
dlpuxdzztg
8,243 PointsAh, it was so obvious! :(
We weren't suppose to make a list of the posts, but a list of the authors! That explains...everything! Thank you so much!
Jeremy Hill
29,567 PointsYea your for loop needs to look like this:
for(BlogPost post : mPosts)
or at least something along those lines. and when you are using the methods from class BlogPost it should look like this:
post.getAuthor()
That is if it is inside your for loop.
dlpuxdzztg
8,243 PointsSo, I read your comment and edited my code...but now i'm super confused where to go from here and if I still need the 'allPosts' list.
public Set<String> getAllAuthors() {
Set<String> allPosts = new TreeSet<String>();
for (BlogPost post : mPosts) {
if (post.equals(post.getAuthor())) {
}
}
return allPosts;
}
This also works:
for (String word : allPosts) {
}
Simon Coates
28,694 PointsIf you read through the other answers and haven't had any luch, try
public Set<String> getAllAuthors() {
Set<String> allPosts = new TreeSet<String>();
for (BlogPost bp : this.getPosts()) {
allPosts.add( bp.getAuthor());
}
return allPosts;
}
Jeremy Hill
29,567 PointsYea lol sometimes I miss those little details as well. Happy coding :)
Philip Gales
15,193 PointsPhilip Gales
15,193 PointsHave you looked at the compiler messages? It looks like it does not like your for each loop.