16-ES6Classes.js

// ES6 classes
class Book {
    constructor (title, pages, isbn) {
        this.title = title;
        this.pages = pages;
        this.isbn = isbn;
    }
    printIsbn(){
        console.log(this.isbn);
    }
}

let book = new Book('title', 'pag',  'isbn');

console.log(book.title); //outputs the book title

book.title = 'new title'; //update the value of the book title

console.log(book.title); //outputs the book title


//inheritance
class ITBook extends Book {

    constructor (title, pages, isbn, technology) {
        super(title, pages, isbn);
        this.technology = technology;
    }

    printTechnology(){
        console.log(this.technology);
    }
}

let jsBook = new ITBook('Learning JS Algorithms', '200', '1234567890', 'JavaScript');

console.log(jsBook.title);
console.log(jsBook.printTechnology());

//getter and setters
class Person {

    constructor (name) {
        this._name = name;
    }

    get name() {
        return this._name;
    }

    set name(value) {
        this._name = value;
    }
}

let lotrChar = new Person('Frodo');
console.log(lotrChar.name);
lotrChar.name = 'Gandalf';
console.log(lotrChar.name);

lotrChar._name = 'Sam';
console.log(lotrChar.name);


//using symbols for private atributes

var _name = Symbol();
class Person2 {

    constructor (name) {
        this[_name] = name;
    }

    get name() {
        return this[_name];
    }

    set name(value) {
        this[_name] = value;
    }
}

let lotrChar2 = new Person2('Frodo');
console.log(lotrChar2.name);
lotrChar2.name = 'Gandalf';
console.log(lotrChar2.name);

console.log(Object.getOwnPropertySymbols(lotrChar2));