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Java Java Data Structures - Retired Getting There Type Casting

Jaroslav Hrdy
Jaroslav Hrdy
652 Points
Posted by Jaroslav Hrdy
Jaroslav Hrdy
652 Points

Problem with challenge 1/2 type casting.

Hi, I am confusing about last challenge. What s wrong in my code?

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 String getTitleFromObject(Object obj){
      if(obj instanceof BlogPost){
            return ((BlogPost) obj).getTitle();
        }
        else{
            return (String) obj;
        }
    }

    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

Jasmeet Singh
Jasmeet Singh
20,145 Points
Jasmeet Singh
Jasmeet Singh
20,145 Points

looks your code is indeed correct. But unfortunately it's in the wrong class. No need to create the method in the BlogPost class.

Your code in the TypeCastChecker class's getTitleFromObject method will do the trick. 

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 BlogPost){
            result = ((BlogPost) obj).getTitle();
        }
        else{
            result =  (String) obj;
        }
    return result;
  }
}