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Java Java Data Structures Getting There Type Casting

Sean Flanagan
Sean Flanagan
33,235 Points

Typecasting Challenge Task 1

Hi.

I've no idea how to do this. Can anyone help please?

Thanks.

Sean

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;
  }
}

2 Answers

Jon Kussmann
PLUS
Jon Kussmann
Courses Plus Student 7,254 Points

Hi Sean,

This is how I solved it. I first checked if 'obj' was a String using the instanceof keyword in Java. If it was the case, I returned the obj cast as a String like so:

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

I hope this helps, if not please let me know.

Sean Flanagan
Sean Flanagan
33,235 Points

Hi Jon.

I pasted your code right below the comment line and it worked. Thank you. :-)

Michael Macdonald
Michael Macdonald
34,265 Points

Hi,

Thanks, I used this code as well, but I don't understand what:

String result = ""; return result;

does at the end of the method.. Is there because we need to return something...?