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Java Java Data Structures Getting There Type Casting

help me with this

challange task 2

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 sethe hint.
  NOTE: You must set all the hints to false to complete the exercise.
  ****************/e 
  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;
    return result;
  }

}
Ignazio Calo
Ignazio Calo
Courses Plus Student 1,819 Points

You should explain what't your problem. In your code some { are missing in the first check

if(obj instanceof String) {
      result=(String)obj;
}

To pass the second you need to do a similar check, but with the BlogPost

    if (obj instanceof BlogPost) {

      BlogPost bp = (BlogPost).obj;
      result = bp.getTitle();
    }

1 Answer

Tony Gemenie
Tony Gemenie
3,781 Points

The main thing is understanding inheritance. Craig created the String Object to use it with multiple types of variables you have to tell it what you're putting in. Good article Here should help you out.