JS code for example

good_code.js

/**
 * This is the detail about the constructor
 * @class Main class for all books
 * @param {String} title Book title
 * @param {String} author Name of author
 * @param {Number} pages How many pages in the book
 */
class Book {
  constructor(title, author, pages) {
    this.title = title;
    this.author = author;
    this.pages = pages;
  }

  get PageCount() {
    return this.pages;
  }

  get AuthorName() {
    return this.author;
  }

  get BookTitle() {
    return this.title;
  }
}

/**
 * @class Type of genre
 * @param {String} title Book title
 * @param {String} author Name of author
 * @param {Number} pages How many pages in the book
  * @param {String} genre Gener of book
 */
class Novel extends Book {
  constructor(title, author, pages, genre) {
    super(title, author, pages);
    this.genre = genre;
  }

  get BookGenre() {
    return this.genre;
  }
}


let book = new Novel('The Hobbit', 'J.R.R. Tolkien', 310, 'Fantasy');