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Java Java Data Structures Getting There Type Casting

Posted by Varun Manoj
Varun Manoj
1,541 Points

Hello there, I think I'm typing in the date format incorrectly?

I'm pretty sure I'm stuck on this exercise because Im not formatting the date format correctly, I thought just using Date() would enter the current date but maybe not?

Thank you for any 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 result;
  public static BlogPost blog= new BlogPost("Daniel","Treet","Bleep","Bloop", Date() );

  public static String getTitleFromObject(BlogPost blog) {
    // Fix this result variable to be the correct string.
   if (blog.getTitle() instanceof String) {

     result= (String) blog.getTitle();
   }



     return result;
  }
}

2 Answers

Kourosh Raeen
Kourosh Raeen
23,733 Points
Kourosh Raeen
Kourosh Raeen
23,733 Points

You don't need to create a BlogPost object and shouldn't change the method's signature from:

getTitleFromObject(Object obj)

to:

getTitleFromObject(BlogPost blog)

You just need to check the type of the variable obj passed in and if it is of type String then cast it to String and then return it. And if it is of type BlofPost then cast it to BlogPost, then call the getTitle() method on it and return it.

Here's the code:

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 String) {
      result = (String) obj; 
    }
    if (obj instanceof BlogPost) {
      result = ((BlogPost) obj).getTitle(); 
    }
    return result;
  }
}
Varun Manoj
Varun Manoj
1,541 Points
Varun Manoj
Varun Manoj
1,541 Points

Thank you!