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Java Java Data Structures - Retired Organizing Data Comparable

How do you solve the second step? Compare with "equals"?

Any hints would be appreciated.

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 int compareTo(Object hello) {
     if (BlogPost.equals(hello))
     {
      return 0;
     }
     return 1;
  }
  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;
  }
}

1 Answer

Florian Tönjes
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Florian Tönjes
Full Stack JavaScript Techdegree Graduate 50,856 Points

Hey magnusmartin,

in the compareTo method you first have to type cast the incoming Object to a BlogPost. Then you have to check if the object that is coming in, named 'hello' in your case, is the same object as the BlogPost that will use this method. Right now you are trying to execute the non-static method 'equals' from the Class BlogPost and not from the instance. Try this instead:

if (this.equals(hello)) // this refers to the instance itself

Kind Regards, Florian