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Java Java Data Structures - Retired Getting There Type Casting

Rebecca Oet
Rebecca Oet
1,349 Points

Java Data Structures Type Casting Issues

I completed the first step easily, but I am having problems with the second. I have tried many things and none of them are working. Currently, I get this message when I try to check my work:

./TypeCastChecker.java:12: error: cannot find symbol public static BlogPost blogpost = new BlogPost("", "", "", "", new Date(1465829029L)); ^ symbol: class Date location: class TypeCastChecker 1 error

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 blogpost = new BlogPost("", "", "", "", new Date(1465829029L));

  public static String getTitleFromObject(Object obj) {
    if(obj instanceof String){
      result = (String) obj;
    }
    if(obj instanceof BlogPost){
      blogpost = (BlogPost) obj;
      result = blogpost.getTitle();
    }
    return result;
  }
}

2 Answers

Kourosh Raeen
Kourosh Raeen
23,733 Points

Hi Rebecca - You don't need to create a BlogPost variable. You can just cast it and then call getTitle() on it:

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;
  }
}
Simon Coates
Simon Coates
28,694 Points

You missed the import statement (import java.util.Date;). That 'cannot find symbol' message tends to come up when java hits something that it doesn't recognize (worth knowing).

Update: Looked at Kourosh Raeen's answer. I ran your code, but didn't read the task. The import is a problem, but you don't need the result and blogpost static fields - the line that creates the import problem. Kourosh Raeen's solution should do the job.