Classes Inheritance and Encapsulation in JavaScript

	//****** Classes Inheritance and Encapsulation **********
	/*** Inheritance b/w classes and constructor functions ***/
	// Contructor Function1
	const Employee = function(firstName, lastName) {
	this.firstName = firstName;
	this.lastName = lastName;
	};
	Employee.prototype.getFullName = function() {
	console.log(`${this.firstName} ${this.lastName}`);
	}
	// Contructor Function2
	const Developer = function(firstName, lastName, level) {
	// this.firstName = firstName;
	// this.lastName = lastName;
	Employee.call(this, firstName, lastName); // To reuse employee
	this.level = level;
	}
	// To inherit the functions present in Employee to Developer
	Developer.prototype = Object.create(Employee.prototype);
	// Developer.prototype = Employee.prototype; // won't work
	Developer.prototype.introduce = function() {
	console.log(`This is ${this.firstName} and I am ${this.level} Developer.`);
	}
	const developerSrinu = new Developer('Srinu', 'SFDC', 'Senior');
	developerSrinu.introduce();
	developerSrinu.getFullName();
	console.log(developerSrinu.__proto__);
	console.log(developerSrinu.__proto__.__proto__);
	console.dir(Developer.prototype.constructor);
	Developer.prototype.constructor = Developer;
	console.dir(Developer.prototype.constructor);
	/*** Inheritance b/w ES6 classes ***/
	class EmployeeCls {
	constructor(firstName, lastName) {
	this.firstName = firstName;
	this.lastName = lastName;
	}
	getFullName() {
	console.log(`${this.firstName} ${this.lastName}`);
	}
	}
	class DeveloperCls extends EmployeeCls {
	constructor(firstName, lastName, level) {
	// No need to use call here use super
	super(firstName, lastName); // this should be the first statement
	this.level = level;
	}
	introduce() {
	console.log(`This is ${this.firstName} and I am ${this.level} Developer.`);
	}
	// Overriding the parent method
	getFullName() {
	console.log(`${this.firstName} ${this.lastName} is my full name.`);
	}
	}
	const khem = new DeveloperCls('Khem', 'Bhole', 'Team Lead');
	// Check khem in console
	khem.introduce();
	khem.getFullName(); // this is from the parent
	/*** Inheritance b/w classes, Object.create ***/
	const EmployeeProto = {
	init(firstName, lastName) {
	this.firstName = firstName;
	this.lastName = lastName;
	},
	getFullName() {
	console.log(`${this.firstName} ${this.lastName} is my full name.`);
	}
	};
	const DeveloperProto = Object.create(EmployeeProto);
	DeveloperProto.init = function(firstName, lastName, level) {
	// To reuse the parent contructor
	EmployeeProto.init.call(this, firstName, lastName);
	this.level = level;
	};
	DeveloperProto.introduce = function() {
	console.log(`This is ${this.firstName} and I am ${this.level} Developer.`);
	};
	const miguel = Object.create(DeveloperProto);
	miguel.init('Miguel', 'M', 'Senior');
	miguel.introduce();
	miguel.getFullName(); // from the parent proto
	/*** ES6 Class Example ***/
	class Account {
	// Public Fields
	locale = navigator.language;
	// Private Fields
	#transactions = [];
	#mobileNumber;
	constructor(fullName, mobileNumber) {
	this.fullName = fullName;
	this.#mobileNumber = mobileNumber;
	// this.transactions = [];
	// this.locale = navigator.language;
	console.log(`Congratulations!!! your account is opened.`);
	}
	// Public Methods
	deposit(amount) {
	this.#transactions.push(amount);
	// To chain the methods
	return this;
	}
	withdraw(amount) {
	this.deposit(-amount);
	// To chain the methods
	return this;
	}
	getTransactions() {
	return this.#transactions;
	}
	requestLoan(amount) {
	if(this.approveLoan(true)) {
	this.deposit(amount);
	console.log('Loan is approved');
	}
	// To chain the methods
	return this;
	}
	// Private Methods
	#approveLoan(isTrue) {
	return isTrue;
	}
	}
	const acc1 = new Account('Gauri C', '878898889',);
	// acc1.transactions.push(900);
	acc1.deposit(900);
	// acc1.transactions.push(-400);
	acc1.withdraw(400);
	console.log(acc1);
	// acc1.approveLoan(true); // should not be accessible
	// console.log(acc1.mobileNumber); // should not be accessible
	// console.log(acc1.#mobileNumber); // Private field '#mobileNumber' must be declared in an enclosing class
	// acc1.#approveLoan(true); // Private field '#approveLoan' must be declared in an enclosing class
	//**** Encapsulation: protecting properties and methods ***
	// Real private and other features are not available in javaScript
	/*** Chaining the methods ***/
	acc1.deposit(800).deposit(900).withdraw(-200);
	console.log(acc1.getTransactions());

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