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Java Java Data Structures Organizing Data Comparable

Priya Patil
Priya Patil
2,471 Points

I am not sure what exactly i have to do here can you please help?

Can you please help me to let know what exactly do i have to code here and how?

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 obj)

    BlogPost another = (BlogPost) obj;
         return 0;
  //  int date = mCreationDate.compareTo(another.mCreationDate);
    //if(date == 1)
   // {
    //return 1;
    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

Allan Clark
Allan Clark
10,810 Points

First, for the another variable, mCreationDate is not accessible directly, you have to use the accessor method getCreationDate().

Next, we are comparing the BlogPosts on basis of their mCreationDate. mCreationDate is of the Date class, which already implements the comparable interface. So instead of creating if statements for each case, we can delegate the comparison to the Date class. We do this by just returning the comparison of the two Dates.

return mCreationDate.compareTo(another.getCreationDate());