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Java Java Data Structures - Retired Organizing Data Comparable

My code is not passing: Ooops! it looks like task 1 is no longer passing

I'm not sure what wrong now

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

import java.util.Date;

public class BlogPost implements Comparable {
  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 int compareTo(Object obj) {
    BlogPost other = (BlogPost) obj;
    if (equals(other)) {
      return 0;
    }
    return -1;
  }
}

1 Answer

Michael Hess
Michael Hess
24,512 Points

Hi Natenda,

Everything looks good.

But, instead of -1 return the following:

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

If you have any questions feel free to ask!

Thank You sooo much Micheal! it worked. can you please explain why we used that return instead of -1?

// return mCreationDate.compareTo(other.mCreationDate);

Michael Hess
Michael Hess
24,512 Points

We want to use compareTo because it returns -1 if the creation date is less than the other.creationDate. It returns 1 if the creation date is greater than other.creationDate. The last task asked us to order the dates in chronological order -- by using compareTo() we can order the dates in chronological order.

How compareTo() works

How Does compareTo() compare Strings?