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Start your free trialJean Malan
10,781 PointsSets Objective - Error: java.lang.reflect.InvocationTargetException
Hey everyone!
Not sure where I have gone wrong and I really don't get the error message that it's giving me - Error: java.lang.reflect.InvocationTargetException
Thanks in advance :)
package com.example;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Date;
import java.util.Set;
import java.util.TreeSet;
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.Arrays;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.Date;
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> sortedAuthors = new TreeSet<String>();
for (BlogPost blogPost : mPosts) {
sortedAuthors.add(blogPost.getAuthor());
System.out.printf("Authors: %S %S", sortedAuthors);
}
return null;
}
}
2 Answers
Richard Lambert
Courses Plus Student 7,180 PointsHello mate,
The utterly mind-boggling world of Java reflection is taught on the Java Turbo Wizard course. I'm going to hazard a guess and say that this particular exception is being thrown as a consequence of the way the underlying Treehouse test engine processes code entered when completing a task. Don't worry about the exception being thrown; instead, focus on these two issues (noted in code):
- Consider the format specifiers declared within the format string, and the type and number of objects being passed into them. For the task set, is this statement necessary?
-
getAllAuthors()
has correctly been declared as returning an object of typeSet<String>
. Is this reflected within the body of the method?
public Set<String> getAllAuthors() {
Set<String> sortedAuthors = new TreeSet<String>();
for (BlogPost blogPost : mPosts) {
sortedAuthors.add(blogPost.getAuthor());
System.out.printf("Authors: %S %S", sortedAuthors); // (1)
}
return null; // (2)
}
Hope this helps
Fahad Mutair
10,359 Pointshi Jean Malan , you got Invocation target exception from this printf , so better to remove it.
System.out.printf("Authors: %S %S", sortedAuthors);
also don't forget to return your set for that method
return null;
Richard Lambert
Courses Plus Student 7,180 PointsHi Fahad Mutair,
How do you get your code snippets to show the source file?
Fahad Mutair
10,359 PointsHello, i used 3 backticks then the name of that file followed by file type 3''Blog.java Then type the line you want
Jean Malan
10,781 PointsJean Malan
10,781 PointsThanks man! That was, although initially confusing to understand, pretty spot on!
Jean Malan
10,781 PointsJean Malan
10,781 PointsNot too sure what that Java Turbo Wizard link was though? haha