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Java Java Data Structures - Retired Getting There Type Casting

Gaspar Santiago
Gaspar Santiago
3,377 Points
Posted by Gaspar Santiago
Gaspar Santiago
3,377 Points

Getting Syntax error, not sure what I'm doing wrong.

Here is the source code:

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;

else if(obj instanceof com.example.BlogPost)//Now make sure that if a com.example.BlogPost is passed in for obj

  result = new (BlogPost) obj.getTitle();//that you then cast it to a BlogPost.
//Return the results of the getTitle method on the newly type-casted BlogPost instance. 

return result;

} }

Can anyone tell me what I'm doing wrong? I don't feel like using "instanceof com.example.BlogPost" is correct but I'm just following the specs verbatim. BTW, Treehouse won't allow me to attach my code so I have to copy and paste it. The "Get Help" button doesn't work while I'm in the exercise.

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 = "";
    return result;
  }
}

1 Answer

Ilya Dolgirev
Ilya Dolgirev
35,375 Points
Ilya Dolgirev
Ilya Dolgirev
35,375 Points

The idea is the same :)

    if (obj instanceof BlogPost) {
      BlogPost post = (BlogPost) obj; // Typecasting obj to BlogPost
      result = post.getTitle(); // Return a string as declared in method signature
    }
Gaspar Santiago
Gaspar Santiago
3,377 Points
Gaspar Santiago
Gaspar Santiago
3,377 Points

I could've sworn I tried that... but perhaps after a few hours, it's easy to miss the smallest detail. I'll give it a go, thanks.