Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

Java Java Data Structures Organizing Data Comparable

"make sure that your class implements the comparable method"

What is missing in my answer? I have a compareTo method, so what else is required to implement the comparable method. This is the first challenge after watching the interface video. Hopefully i have provided enough information to get the right help. Thanks!

com/example/BlogPost.java
package com.example;

import java.util.Date;

public class BlogPost {
  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 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;
  }

  public class ToCompare implements Comparable  {
  @Override
  public int compareTo(Object obj) {
    ToCompare other = (ToCompare)obj;
    if (equals(other)) {
        return 1;
      }
        return 1;
     }
   }
 }

2 Answers

Seth Kroger
Seth Kroger
56,407 Points

BlogPost is the class that should implement Comparable, not an inner class inside of it.

public class BlogPost implements Comparable {
  // ...
   @Override
   public int compareTo(Object obj) {
        return 1;
   }
}

Thank you for responding. Interesting enough, your response was how I first implemented my code. I got back the following:
error: class BlogPost is already defined in package com.example public class BlogPost implements Comparable {....

The results were the same from when I first tried it myself before applying what you provided as well...

Something is still missing. Thanks!

Kourosh Raeen
Kourosh Raeen
23,732 Points

The BlogPost class needs to implement the Comparable interface:

public class BlogPost implements Comparable {
...

Thank you for responding. Interesting enough, your response was how I first implemented my code. I got back the following:
error: class BlogPost is already defined in package com.example public class BlogPost implements Comparable {....

The results were the same from when I first tried it myself before applying what you provided as well...

That is the reason for coding in a made up class...

Something is still missing. Thanks!