cast checker

Question

task 1 of the cast checker challenge

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.
    String result = "";

    return result;


  }
}

Answer 1 · 2017-11-28T21:12:24Z

November 28, 2017 9:12pm

Hi there....

Yeah type casting can be confusing at first isn't it? Moreover since Craig uses REPL to demonstrate what it is instead of compiled it into console. But basically he wanted you to type cast the String class object to variable called obj. But in order to make sure it will not create an error when compiled you need to make sure that obj is an instance of String class. Here is the code I propose to be used:

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;
  }

I hope this will help a little to pass the challenge.

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Pengcheng Zhai

Pengcheng Zhai

cast checker

1 Answer

Yanuar Prakoso

Yanuar Prakoso