What am I doing wrong?

Question

So I can't seem to get this to work for the challenge 2. Any help why?

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 BlogPost(String author, String title, String body, String category, Date creationDate) {
      mAuthor = author;
      mTitle = title;
      mBody = body;
      mCategory = category;
      mCreationDate = creationDate;
    }

    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;
    }
}

TypeCastChecker.java

import com.example.BlogPost;

public class TypeCastChecker {
  /***************
  I have provided 2 hints for this challenge.
  Change `false` to `true` in one line below, then click the "Check work" button to see the hint.
  NOTE: You must set all the hints to false to complete the exercise.
  ****************/
  public static boolean HINT_1_ENABLED = false;
  public static boolean HINT_2_ENABLED = false;

  public static String getTitleFromObject(Object obj) {
    // Fix this result variable to be the correct string.
    String result = "";

    if(result instanceof Object)
    {
      return (String)obj;
    }
    return (String)obj;

    BlogPost post = (BlogPost)obj;
    if(post instanceof Object)
    {
      return post.getTitle();
    }
    return post.getTitle();
  }
}

Answer 1 · 2017-11-09T11:52:49Z

November 9, 2017 11:52am

Your check is wrong - if(result instanceof Object).

This will always return true, because all objects inherit from Object. Since you have a return statement with the check which always results true, the second part of your code never executes -

if(result instanceof Object)
    {
      return (String)obj;
    }

Also, you shouldn't be checking result in the instanceof comparison. Use the passed in argument obj instead. In the first part, check if it's an instance of String, and for the second part -BlogPost.

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Akhil Matabudul

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What am I doing wrong?

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Manish Giri

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Akhil Matabudul

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