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Start your free trialDeano k
Courses Plus Student 5,872 PointsWhat's wrong with my code?
getting an InvocationTargetException error message.. :/ What did I do wrong?
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.Set;
import java.util.TreeSet;
import java.util.Map;
import java.util.HashMap;
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> catCount = new HashMap<String, Integer>();
for (BlogPost post : mPosts) {
Integer count = catCount.get(post.getCategory());
if (count == 0) {
count = 0;
}
count++;
catCount.put(post.getCategory(),count);
}
return catCount;
}
}
1 Answer
Jeremy Hill
29,567 PointsHere is the code that worked for me:
public Map<String, Integer> getCategoryCounts(){
Map<String, Integer> categoryCounts = new TreeMap<>();
Integer count = 0;
for(BlogPost post: mPosts){
count = 0;
for(BlogPost bp: mPosts){ // I used a nested for loop here to count all of the like categories for each element.
if(post.getCategory() == bp.getCategory()){
count++;
}
}
categoryCounts.put(post.getCategory(), count); // after the inner loop ends I added the current element of the outer loop to the map.
}
return categoryCounts;
}