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Java Java Data Structures Organizing Data Comparable

Ronald Greer
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Ronald Greer
Front End Web Development Techdegree Graduate 56,430 Points
Posted by Ronald Greer
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Ronald Greer
Front End Web Development Techdegree Graduate 56,430 Points

can someone please help

it says i have a syntax error

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 int compareTo(Object obj){
    if(obj instanceof BlogPost){
      BlogPost bp = (BlogPost) obj;
      return 0;
    }
    int dateComp = mCreationDate.compareTo(other.mCreatonDate);
    return 1;
  }


  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;
  }
}

3 Answers

Yanuar Prakoso
Yanuar Prakoso
15,196 Points
Yanuar Prakoso
Yanuar Prakoso
15,196 Points

Hi Ronald

As the challenge task says: You need to implements Comparable interface to the class and then add Object type into method called compareTo then you need to modify the class name first:

import java.util.Objects;

public class BlogPost implements Comparable{

do not forget to add import java.util.Objects since you want to add an Object later in the compareTo method.

Then you were asked to produce a compareTo method that accepts an object as a parameter. Have it always return 1 for this first step so please just do that first:

@Override
public int compareTo(Object object) {
    return 1;
  }

Later on this challenge you will get the opportunity to use more complicated code in the compareTo method. For this first task just keep it simple okay.

I hope that can help

Yanuar Prakoso
Yanuar Prakoso
15,196 Points
Yanuar Prakoso
Yanuar Prakoso
15,196 Points

This is my code for passing the first challenge:

package com.example;

import java.util.Date;

import java.util.Objects;//<--- import this

public class BlogPost implements Comparable{//<-- do not forget to implements Comparable
  private String mAuthor;
  private String mTitle;
  private String mBody;
  private String mCategory;
  private Date mCreationDate;

//erase all your added code from before 
  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 object){//<-- add this code
    return  1;
  }
}

please check again

Yanuar Prakoso
Yanuar Prakoso
15,196 Points
Yanuar Prakoso
Yanuar Prakoso
15,196 Points

just modify your compareTo method to be:

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