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Java Java Data Structures - Retired Getting There Type Casting

Amrit Pandey
Amrit Pandey
17,595 Points
Posted by Amrit Pandey
Amrit Pandey
17,595 Points

Please help me with this challenge! JAVA

I did casted obj if it was instanceof String but the challenge is not passing.

if(obj instanceof String){
    return (String) obj;
}
return "";
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

Ben Jakuben
STAFF
Ben Jakuben
Treehouse Teacher
Ben Jakuben
Ben Jakuben
Treehouse Teacher

Where did you insert that instanceof and casting code? I was able to pass this challenge by inserting that into the getTitleFromObject() method in the TypeCastChecker.java file.

Amrit Pandey
Amrit Pandey
17,595 Points
Amrit Pandey
Amrit Pandey
17,595 Points

Yeah sorry, I just saw and remembered. I had to hit refresh button before submitting the code due to internet problem. I may have missed the code to insert.

here it is:

public static String getTitleFromObject(Object obj) {
    String result = "";
    if(obj instanceof String){
       return (String) obj
    }
    return result;
  }

If the obj is instance of String it must return obj casted as String! I did the same, but code challenge do not pass.

Ben Jakuben
Ben Jakuben
Treehouse Teacher
Ben Jakuben
Ben Jakuben
Treehouse Teacher

When I just tried your code, I got a syntax error because you'er missing a semicolon on your return (String) obj line. Fix that and it works!

As a side note, I like to avoid multiple return statements in a method because it can get hard to follow or troubleshoot. As an alternative, instead of returning a value inside the if statement, I just set the result variable:

result = (String)obj;