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Java Java Data Structures Getting There Type Casting

Timmie Nilsson
Timmie Nilsson
4,463 Points

getTitleFromObject

Why wont this work? This is step one of the task where we are suppose to check is the obj is a String and if it is return it.

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

1 Answer

Hi there,

You have your return statement inside your if statement, so the method might not return something. Java thinks your method will return a String; currently, it might not.

So, move the closing curly brace of the if statement before the return statement:

  public static String getTitleFromObject(Object obj) {
    // Fix this result variable to be the correct string.
    String result = "";
    if(obj instanceof String){
      result = (String) obj;
    } // <- I moved that
    return result;
  }

That'll work fine.

Steve.

No problem, Timmie! :+1: :+1: :+1: