Type Casting 2nd quiz

Question

I tried to slove the 2nd task in couples of time, but I have no idea what to do. The task is Now make sure that if a com.example.BlogPost is passed in for obj that you then cast it to a BlogPost. Return the results of the getTitle method on the newly type-casted BlogPost instance.

I just added BlogPost instance.

Please give me a hint how to get the the result of the getTitle method ?

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;
import java.util.Date;

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;

 BlogPost blogpost = new BlogPost("david","a flower","the red","Roman",new Date());



  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;
  }
}

Answer 1 · 2019-02-04T20:06:25Z

February 4, 2019 8:06pm

You can do an else if and check if the obj being passed is an instanceof BlogPost, if it is, then cast it to a BlogPost object, like you did with String, then you can call getTitle() and return that String.

else if(obj instanceof BlogPost){
    BlogPost blogPostObj = (BlogPost) obj; 
    //now you have a BlogPost object 
}

Welcome to the Treehouse Community

Looking to learn something new?

Yasunori Iwazaki

Yasunori Iwazaki

Type Casting 2nd quiz

1 Answer

Emmanuel C

Emmanuel C

Yasunori Iwazaki

Yasunori Iwazaki