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Java Java Data Structures - Retired Getting There Type Casting

mihai tudose
mihai tudose
3,029 Points

i don't understand what i m asked to do .Please help

What should i return?

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 = true;
  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){
    return result;
  }
    return result;
  }
}

1 Answer

Florian Stegemann
seal-mask
.a{fill-rule:evenodd;}techdegree
Florian Stegemann
Full Stack JavaScript Techdegree Student 22,660 Points

The exercise wants you to cast the Object obj, that was passed into getTitleFromObject to a String and assign that String to result. You are already correctly checking wether obj is actually a String, so inside your if statement you can now safely cast obj to String and assign it. Remember, you can just cast a type to another type by putting the target type in parentheses before the variable.

Example:

result = (typeName)myVariable;