conditions 12 and 13 not validating.

Question about the task

OOP: Books

Java Core, Level 5, Lesson 2

Under discussion

What's wrong in my code?

1. Create a public static class MarkTwainBook that inherits Book. Name of the author [Mark Twain].
The constructor parameter is the book title.
2. Implement all the abstract methods in the MarkTwainBook class.
3. Change the return type of the getBook method to make it more appropriate.
4. In a similar manner, create the AgathaChristieBook class. Name of the author [Agatha Christie].
5. In the Book class, implement the getOutputByBookType method so that it returns:
5.1. agathaChristieOutput for books written by Agatha Christie;
5.2. markTwainOutput for books written by Mark Twain.

Requirements:

The Solution class must contain the public static MarkTwainBook class.
The MarkTwainBook class must be a descendant of the Book class.
The MarkTwainBook class must correctly implement a constructor with one String parameter (book title).
The MarkTwainBook class constructor should call the constructor of the parent class (Book) with the argument "Mark Twain".
The getBook method in the MarkTwainBook class must have the MarkTwainBook return type and return the current object.
The Solution class must contain the public static AgathaChristieBook class.
The AgathaChristieBook class must be a descendant of the Book class.
The AgathaChristieBook class must correctly implement a constructor with one String parameter (book title).
The AgathaChristieBook class constructor should call the constructor of the parent class (Book) with the argument "Agatha Christie".
The getBook method in the AgathaChristieBook class must have the AgathaChristieBook return type and return the current object.
The getTitle method in the AgathaChristieBook and MarkTwainBook classes should return the title of a specific book.
The getOutputByBookType method must return the correct string for AgathaChristieBook objects.
The getOutputByBookType method must return the correct string for MarkTwainBook objects.
The MarkTwainBook class must have a String field title (book title).
The AgathaChristieBook class must have a String field title (book title).

package com.codegym.task.task15.task1504; import java.util.LinkedList; import java.util.List; /* OOP: Books */ public class Solution { public static void main(String[] args) { List<Book> books = new LinkedList<Book>(); books.add(new MarkTwainBook("Tom Sawyer")); books.add(new AgathaChristieBook("Hercule Poirot")); System.out.println(books); } abstract static class Book { private String author; public Book(String author) { this.author = author; } public abstract Book getBook(); public abstract String getTitle(); private String getOutputByBookType() { String agathaChristieOutput = author + ": " + getBook().getTitle() + " is a detective"; String markTwainOutput = getBook().getTitle() + " was written by " + author; String output = "output"; //write your code here return agathaChristieOutput + markTwainOutput + getBook().getTitle(); } public String toString() { return getOutputByBookType(); } } public static class MarkTwainBook extends Book { private String title; public MarkTwainBook(String title) { super("Mark Twain"); this.title = title; } public MarkTwainBook getBook() { return this; } public String getTitle() { return this.title; } } public static class AgathaChristieBook extends Book { private String title; public AgathaChristieBook(String title) { super("Agatha Christie"); this.title = title; } public AgathaChristieBook getBook() { return this; } public String getTitle() { return this.title; } } }

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Cinthya Cabanzo

Level 22 , Bogota, Colombia

14 June 2019, 23:19

Or you can use

if ( this instanceof MarkTwainBook) {
               output = markTwainOutput;

Abhishek Rangari

Level 22 , Nagpur, India

27 November 2018, 15:05

programmer, you just need to adjust the getOutputByBookType(), we need to send the output from this method based on the author field in the class.

String output = null;
            //write your code here
            if(author.equals("Agatha Christie")){
                    output = agathaChristieOutput;
            }else if(author.equals("Mark Twain")){
                    output = markTwainOutput;
            }

return output;

I hope this will help you out.

Roman

Level 41

16 November 2018, 10:50

From the condition: ...getOutputByBookType method so that it returns: 5.1. agathaChristieOutput for books written by Agatha Christie; 5.2. markTwainOutput for books written by Mark Twain. These are two different outputs!