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Jason Anello
Courses Plus Student 94,610 PointsYour method looks good but you forgot to import Map
and HashMap
import java.util.Map;
import java.util.HashMap;
jinhwa yoo
10,042 PointsIn Blog.java add a new method called getCategoryCounts. It should return a Map of category to count calculated by looping over all the posts.
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> authors = new TreeSet<>();
for (BlogPost post: mPosts) {
authors.add(post.getAuthor());
}
return authors;
}
public Map<String, Integer> getCategoryCounts() {
Map<String, Integer> categoryCounts = new HashMap<String, Integer>();
for (BlogPost post : mPosts) {
String category = post.getCategory();
Integer count = categoryCounts.get(category);
if (count == null) {
count = 0;
}
count++;
categoryCounts.put(category, count);
}
return categoryCounts;
}
}
Jason Anello
Courses Plus Student 94,610 PointsJason Anello
Courses Plus Student 94,610 PointsHi jinhwa,
What code are you trying?