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Java Java Data Structures - Retired Getting There Type Casting

angel juarez
angel juarez
15,886 Points

I'm having problems casting obj as BlogPost. I'm not sure if the method should return a String or a BlogPost object.

I'm doing the second part of the casting challege. I was able to cast obj as String but I can't do the same for BlogPost

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.
    BlogPost result;
    if(obj instanceof BlogPost){
      result = new BlogPost();
    }
    return result.getTitle();
  }
}

1 Answer

It should return a String (the title). But it should accept either a String or a BlogPost object as a parameter. You need to find out if the parameter object is a String or a BlogPost. If it's a String, you cast it as String and return it. If it's a BlogPost, you cast it as BlogPost and return the title of the BlogPost using the getTitle() method of the BlogPost object.