Cant get this one right

Question

help me where I am wrong

com/example/BlogPost.java

package com.example;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;



public class BlogPost implements Comparable<BlogPost>, Serializable {
  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(BlogPost other) {
    if (equals(other)) {
      return 0;
    }
    return mCreationDate.compareTo(other.mCreationDate);
  }

  public String[] getWords() {
    return mBody.split("\\s+");
  }

  public List<String> getExternalLinks() {
    List<String> links = new ArrayList<String>();
    for (String word : getWords()) {
      if (word.startsWith("http")) {
        links.add(word);
      }
    }
    return links;
  }

  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;
  }
}

com/example/Blog.java

package com.example;

import java.util.List;
import java.util.Set;
import java.util.TreeSet;

public class Blog {
  List<BlogPost> mPosts;

  public Blog(List<BlogPost> posts) {
    mPosts = posts;
  }

  public List<BlogPost> getPosts() {
    return mPosts;
  }
  public Set<String> getAllAuthors(){
    Set<String> allAuthors = new TreeSet<String>();
    for( Blog bp : posts ){
       allAuthors.add(bp.getPosts());
    }
    return allAuthors;
  }
}

Answer 1 · 2017-09-07T09:56:53Z

September 7, 2017 9:56am

Hey Aditya, I see a couple of mistakes in your getAllAuthors() method.

To get the posts in your for loop, you need to call the getPosts() method defined above. +The variable 'bp' that you used has to be of the type BlogPost for the loop to work as it'll run through a list of Blog Posts. Makes sense? Hope that helps

Answer 2 · 2017-09-08T05:36:52Z

September 8, 2017 5:36am

That fine , but I never created an object in the blogPost class. If you see in the tutorial they have created objects and then called.

Answer 3 · 2017-09-08T05:39:39Z

September 8, 2017 5:39am

public Set<String> getAllAuthors(){ Set<String> allAuthors = new TreeSet<String>(); for( BlogPost bp : getPosts() ){ allAuthors.add(bp.getPosts()); } return allAuthors; }

can yo help me with this part of code

Answer 4 · 2017-09-08T13:10:08Z

September 8, 2017 1:10pm

You don't have to create a new instance of BlogPost object as the getPosts() method returns a list of BlogPost objects. As they are already of type BlogPost, you can use on them the methods offered by the BlogPost class.

Coming to your second question, as I see, getAllAuthors() method returns the Set of all authors.

The first line instantiates a new Set which is to be filled by the authors.
The statement of for loop goes like for each bp of type BlogPost in the List returned by getPosts(), get the author and add it to the allAuthors Set.
After the loop ends, return the Set of allAuthors.

In your code, I see that in the for loop, you are adding bp.getPosts() instead of bp.getAuthor() to the Set. Remember that you are supposed to add the authors in the Set.

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Aditya verma

Aditya verma

Cant get this one right

4 Answers

Hassaan Ahmad

Hassaan Ahmad

Aditya verma

Aditya verma

Aditya verma

Aditya verma

Hassaan Ahmad

Hassaan Ahmad