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Java

Posted by Joseph Wasden
Joseph Wasden
20,407 Points

Using ArrayLists - "Expected 3 links to be found, but received 13" error?

(Side note: I can't seem to get the Get Help button to work when asking questions. when I click it, it changes to dark green, then nothing happens.)

I am working on the Java ArrayLists challenge, and I've whittled out all of my error messages. However, when I check my work I get an error of ""Bummer! Expected 3 links to be found, but received 13."

I'm not really sure how that is a problem. My first thought is, "well, if I found 13, there are 13 to be found!" but Since this is a pretty controlled challenge, I doubt that's the right approach. :)

Perhaps I need to refine my startsWith() paramenter of "http" ? but, that is the param suggested in the notes.

Any idea as to why I would get this error? I've included the code, and commented at areas I've added.

package com.example;

import java.io.Serializable;
import java.util.Date;
import java.util.ArrayList; //added for the challenge
import java.util.List; // added for the challenge

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);
  }

   /*
    Let's add a method that returns a list of all links in the body of the document. 
    All words that start with http should be considered links. Name it getExternalLinks. 
    NOTE: Remember to import the needed classes from java.util. 
    HINT: We already made the getWords method, we should use it!
  */

  //startcode
  public List<String> getExternalLinks() {
    List<String> linkResults = new ArrayList<String>();
    for (String word : getWords()) {
      if (word.startsWith("http")) {
      }
    linkResults.add(word);
    }
    return linkResults;
  }
//endcode

  public String[] getWords() {
    return mBody.split("\\s+");
  }

  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;
  }
}

3 Answers

Alexander Nikiforov
.a{fill-rule:evenodd;}techdegree seal-36
Alexander Nikiforov
Java Web Development Techdegree Graduate 22,175 Points

Let me give you a hint: You have error in this method. Do you see how your if() has empty body: no code inside braces. That's why instead of using if you are adding ALL words but not the ones that start with "http". Do you see where I lead to and how to fix this?

  //startcode
  public List<String> getExternalLinks() {
    List<String> linkResults = new ArrayList<String>();
    for (String word : getWords()) {
      if (word.startsWith("http")) {
      }
    linkResults.add(word);
    }
    return linkResults;
  }
Joseph Wasden
Joseph Wasden
20,407 Points

Oh man. I don't know how I missed that. Thanks. :)

Joshua marais
Joshua marais
2,955 Points
Joshua marais
Joshua marais
2,955 Points

try this it passes task 1 & 2. paste the code at the bottom

public int compareTo(Object obj){ BlogPost other = (BlogPost) obj; if (!equals(other)){ return 1; }else{ if(equals(other)) return 0; } return mCreationDate.compareTo(other.mCreationDate); } }

Anand Altekar
Anand Altekar
1,790 Points
Anand Altekar
Anand Altekar
1,790 Points

What am I doing wrong here? I get the same exact error mentioned above.

package com.example;

import java.io.Serializable; import java.util.Date; import java.util.List; import java.util.Arrays; import java.util.ArrayList;

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 List<String> getExternalLinks() { List <String> results = new ArrayList <String>(); for (String word : getWords()) { if (word.startsWith("http")); { results.add(word); } } return results; }

public String[] getWords() { return mBody.split("\s+"); }

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; } }