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Java Java Data Structures Getting There Type Casting

Object cannot find method

I have created a BlogPost and imported the com.example.BlogPost, but the new BlogPost called obj that I created cannot find the getTitle() method from the com.example.BlogPost file.

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;
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;
    } else {
      obj = (BlogPost) obj;
      //obj = BlogPost("Abby H", "Treet", "body", "category", new Date()) ;
      result = obj.getTitle();
    return result;

1 Answer

The error is coming from where you are trying to cast the object. Currently you are trying to access getTitle from the Object class and the Object class does not have a getTitle method. To fix this you need to change the casting to

result = ((BlogPost) obj).getTitle();

and remove your other casting. You can not cast a Parent class to a child class but you can access the child class methods if the class is indeed a Child of the parent. Since all Classes are Children of the Object class you do this by accessing the Child methods as shown above.

Hope this helps!