Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Java Java Data Structures - Retired Getting There Type Casting

Vidhya Sagar
Vidhya Sagar
1,568 Points

(Struck) TypeCasting.

I get an error saying that objects cannot be converted to strings .

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 = "";
    BlogPost result1;
    if (obj instanceof String){
      result=(String)obj;
      return result;
    }
    else if (obj instanceof BlogPost){
      result1=(BlogPost)obj;
  return result1;    
    }
   }
}

1 Answer

andren
andren
28,558 Points

The error comes from the fact that the method has a return type of String, which means that you cannot return anything besides a String.

You seem to have missed this part of the task instructions:

Return the results of the getTitle method on the newly type-casted BlogPost instance.

You are not meant to return the BlogPost object itself, but the title of the blog post which you get by running the getTitle method on the BlogPost object after you cast it.

Vidhya Sagar
Vidhya Sagar
1,568 Points

Thanks man.Worked like a charm.