How do I downcast from a BlogPost to String?

Question

I'm on the Java data structures course challenge. It wants me to return a String value after checking the instanceof the object to determine if I can downcast it to a string. I don't know how to solve this.

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 (obj instanceof String){
      result = (String) obj;
      return result;
    }
    else if (obj instanceof BlogPost){
      BlogPost returnBlogPost = obj.getTitle();
      return returnBlogPost;
    }

  }
}

Answer 1 · 2016-12-30T20:53:47Z

December 30, 2016 8:53pm

  public static String getTitleFromObject(Object obj) {
    // Fix this result variable to be the correct string.
    String result = "";
    if (obj instanceof String){
        result = (String) obj;
        //removed return statement
    } 
    else { //<----if obj is not a string then it is a blogpost
        //casted obj to a blogpost
        BlogPost returnBlogPost = (BlogPost) obj;
        //set result to the new variable.getTitle
        result = returnBlogPost.getTitle();
    }

    //return the result variable
    return result;
  }

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How do I downcast from a BlogPost to String?

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