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Java Java Data Structures Getting There Type Casting

Carlo Antonio Bilbao
Carlo Antonio Bilbao
24,113 Points

Java Type Casting: Task 2

I've completed the first task, but cant seem to get the second one to pass. I think i have my if statement correct. But the code inside is lacking. How do i access the getTitle string and set it equal to the result? I'm trying to pass the obj into the BlogPost Class and retrieve the getTitle result. Help.

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 = "random";
    if (obj instanceof String) {
      result = (String) obj;
    }
    if (obj instanceof BlogPost) {
      result = BlogPost(obj).getTitle();
    }
    return result;
  }
}

2 Answers

Craig Dennis
STAFF
Craig Dennis
Treehouse Teacher

The parenthesis go around the type:

(BlogPost) obj ...

// vs.

BlogPost (obj) ...

Common misunderstanding, hope it helps!

Irving Amador
Irving Amador
7,488 Points

I think first you have to create a BlogPost variable and store in it the obj value which has a BlogPost content. Then store the result from colling the getTtitle method in the result variable which is expecting a string value.