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Java Java Data Structures Organizing Data Comparable

Priyatham Kunarapu
Priyatham Kunarapu
1,350 Points

Confused about ordering.

I couldn't solve the Task 3 in this Interfaces code Challenge.

com/example/BlogPost.java
package com.example;
import java.util.Arrays;
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 int compareTo(Object obj){
    BlogPost post = (BlogPost) obj;
    if(equals(post)){
      return 0;
    }
    return 1;
  }

  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;
  }
}

1 Answer

cm21
cm21
150,854 Points

Hi Priyatham,

Task 3 asks us to, instead of returning 1, have the blog posts ordered chronologically by creation date. We can accomplish this through the use of the compareTo method, and specifying our post object's creation date as what needs to be compared.

Therefore, you'll want to get rid of the 'return 1;' and replace it with:

    return mCreationDate.compareTo(post.mCreationDate);

Hope this helps!

Priyatham Kunarapu
Priyatham Kunarapu
1,350 Points

I have already tried it. It doesn't work. I think we should sort.