Forem: Sivakumar Mathiyalagan

JavaScript Scenario Question-2

Sivakumar Mathiyalagan — Fri, 17 Apr 2026 16:03:22 +0000

Question 1:

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Object & Array Scenario Questions

Sivakumar Mathiyalagan — Thu, 16 Apr 2026 15:31:25 +0000

User Profile Update

Shopping Cart Total

3.Find Specific Object

4.Add Item to Array

5.Count Items in Object

6.Convert Array to Object

Group Users by Role

git url https://gitlab.com/sivakumar_mathiyalagan/scenario-exercises.git

Array Iteration Methods

Sivakumar Mathiyalagan — Wed, 15 Apr 2026 15:23:48 +0000

forEach() :

1.This method accepts another function as an Argument(callback Function) to perform certain operation on the array it is iterating
2.To call any of the iteration method must check these criteria

must need an object to call the method
what argument need to be passed
what return type the iteration method provides

forEach method takes 3 arguments

The item value
The item index
The array itself

And forEach method returns nothing

output:

map()

Unlike forEach method map method retuns a new Array
It doesnot mutate the original Array
If some index value is not defined in an array for Example
[1,2, ,3,4]

output:

flatMap()

This method transforms each element into an array, then flattens it one level
map method returns single value make the resultant array as a nested array
whereas flatMap removes the nested format one level deep by default
let's see with example

in map method:

output:

Using flatMap method:

output:

filter()

This method creates a new array with the filtered value based on the condition provided through call back function

output:

reduce()

This method reduce the array to single value
this runs from left to right but it does not alter the original array

this methos takes 4 arguments

The total (the initial value / previously returned value)
The item value
The item index
The array itself

output:

SDLC [Software Development Life Cycle] and its Models

Sivakumar Mathiyalagan — Tue, 14 Apr 2026 06:42:02 +0000

WHAT IS SDLC ?
SDLC is a structured process from initial stage to deployment and maintanence of a software, It defines each stage of the software development typically 6 to 7 phase based on the development model

Planning
Analysis
Design
Coding
Testing
Deployment
Maintenance

PLANNING:

This stage determines whether the project is technically, financially, and operationally feasible
The planning phase often produces an initial software requirement specification (SRS) document. The SRS details the software’s functions, required resources, possible risks and project timeline

ANALYSIS:

During the analysis phase, the development team collects and analyzes information on the project’s requirements
At the end of the analysis phase, project managers and development teams fully understand the scope of the project, its functional and technical specifications and how to organize project tasks and workflows

DESIGN:

In this phase the requirement is converted to blueprint format to determine how the software flow is going to be. this involves High-Level Design (HLD) and Low-Level Design (LLD)
Design phase work is collected in a software design document (SDD), which is passed on to developers as a roadmap to use while coding
HLD - Defines system architecture, technology stack, database design, and major modules
LLD - Specifies component logic, APIs, data structures, and workflows

CODING:

In this phase developers starts to code based on the SRS and SDD which determines the coding language, integrate modules, server connection, API calls, UI are developed in this phase, often UNIT testing is also performed by developers at this stage

TESTING:

This phase comes after the development phase once the software becomes functional, based on the SRS the testing will be conducted and ensured if the developed software meet its expected result
Manual Testing and Automation Testing are performed during this phase

DEPLOYMENT:

In this phase the developed software is deployed into the server and made available for the users
Developers might deploy software in phases—such as a beta release, where a limited group of users tests an early version of the software—before releasing it to the public

MAINTANANCE:

Post-deployment support to ensures long-term usability
Bug fixes, performance tuning, updates, feature enhancements are the features of Maintanance phase

SDLC MODELS:

Waterfall Model
Agile Model
V-Model
Spiral Model
Incremental Model
RAD Model

WATERFALL MODEL:
It is a linear and sequential software development model
To forward or move to next stage previous stage must be completed
This provide structured and predictable process that works for well defined requirement
But this model is not very flexible as it does not allow backtracking and permits only minimal changes once a phase is completed

V-MODEL:
It is a method that includes testing and validation alongside each development phase. It creates a structure like the letter 'V'
This is also called as modified waterfall model and verification and validation model. In each phase of the SDLC has its own accompanying testing phase

AGILE:
The agile model runs on continuous improvement and development cycles—often called "sprints"-in which developers regularly make and release small, incremental changes
It is responsive to changing requests or requirements, enabling teams to more easily identify issues during the development process
It is more commonly used model in current SLDC

Software Testing

Sivakumar Mathiyalagan — Mon, 13 Apr 2026 07:46:23 +0000

WHAT IS SOFTWARE TESTING ?
It is a process of evaluating the software that is developed and ensuring that it meets the client requirement
It involves

Identifying bugs
fixing errors
Missed client Requirement

TYPES OF SOFTWARE TESTING ?

Manual Testing
Automation Testing

WHAT IS MANUAL TESTING ?

In Manual testing the test cases are executed by person and not by automation tools. Tester verify the test case scenarios and compare the test result with the expected result
It is a hands on approach to test a software and person involved in testing finds the bug and errors(user like approach)
Every new application must be manually tested before its testing can be automated
Unlike automated testing, manual testing relies on predefined test cases and can be time-consuming and prone to human error

WHAT IS AUTOMATION TESTING ?

In Automated testing user writes test cases in script format and executes those test cases using some automation tools. It allows to execute repetitive task without requiring manual support
It is more reliable than manual testing
compared to manual testing it is less time consuming and less human error
some popular automation tools are
Selenium
QTP(Quick Test Professional)
Sikuli
Appium
Jmeter

TYPES OF MANUAL TESTING ?

White Box Testing
Black Box Testing
Grey Box Testing

BLACK BOX TESTING:
Checks functionality without knowing internal code. It focuses only on inputs and expected outputs.

No knowledge of code required
Based on requirements and user perspective
Used for functional testing

WHITE BOX TESTING:
Involves testing with knowledge of internal code structure. It focuses on logic, conditions, and code paths.

Requires programming knowledge
Tests loops, conditions, and branches
Ensures code correctness and coverage

GREY BOX TESTING:
This is a combination of both white box and black box tesing, tester need to perform function test and also need to have coding knowledge to check the internal structure. if some test case fails tester will then make some changes in coding part

NOTE:

Smoke Testing
Sanity Testing
Regression Testing
Acceptance Testing are also some testing techniques available

WHAT IS FUNCTIONAL AND NON-FUNCTIONAL TESTING ?

FUNCTIONAL TESTING:

This type of testing checks the each functionality of the software with different test inputs and verify the output with the expected output
This testing is not concerned with the source code of the application
This testing focuses on checking the user interface, APIs, Database, Security, Client or Server Application, and functionality of the Application Under Test.

WHAT IS NON-FUNCTIONAL TESTING ?
This type of testing verify if the performance and behaviour of the software is as per requirement
Performance testing: checks how the software handles the numbers of user and sometimes overload to check its scalability and performance
Security testing: checks the various aspects of vulnerability and threats and checks if software is protected from those vulnerabilities
Load testing: This checks if multiple users are access the software at same time and how the software behaves in time to respond or to load data.

Server

Sivakumar Mathiyalagan — Sat, 11 Apr 2026 16:12:10 +0000

What is a server?

A server is a hardware device or software that process the request sent by the client through a network and replies or response to them
Client is a device that sends the request and wait for the response from the server
Multiple clients can be served by a single server, and a single client can use multiple servers.
These machines run on a client-server model, where clients request specific services or resources, and the server fulfills these requests.

client-server model is not the only model but most commonly used

Peer-to-Peer (P2P) Model
Distributed Systems
Microservices Architecture
Serverless Architecture
Hybrid Models are some of the other server models

What does a server do?

Data storage and retrieval
One of the primary function of server is to store and manage data
data of anytype like documents, media files most common response format is JSON(JavaScript Object Notation)

Website hosting
When you browse the internet, the web pages you access are typically hosted on web servers. These servers store the website’s files and deliver them to your web browser when you request a page.

Email services
Email servers manage the flow of electronic messages. They receive, store, and distribute emails to their intended recipients. Additionally, they handle tasks such as spam filtering and user authentication.

Application hosting
Many applications and software services are hosted on servers rather than running on individual devices. These servers provide the necessary computing power and resources to run applications

File sharing
Stores and lets users share files over a network, Authorization can be implemented to avoid breach of sensitive data.

Database Server
Provides database access and handles queries
following are some database servers

MySQL
PostgreSQL
Oracle Database
Microsoft SQL Server
MongoDB

Game Server
Hosts online multiplayer games and syncs game data between players

Why are servers important?

Without server internet might be of no use because server plays the major role in shaping how we communicate, access information, conduct business, and store data.
Every websites, mobile application, streaming platform, business Application or socail media utilize servers to host, store data, to store media files or even to authenticate users

Referred in geekforgeeks.org & serverwatch.com

Javascript questionnaire 2

Sivakumar Mathiyalagan — Sat, 11 Apr 2026 08:57:02 +0000

Different types of operators?
Plus +
Minus -
Increment ++
Decrement --
Multiply *
Exponentiation **
Division /
Modulas %
And &&
OR ||
Assignment =
Equal to ==
Not !
strict equality operator ===
+= x += y x = x + y
-= x -= y x = x - y
= x *= y x = x * y
/= x /= y x = x / y
%= x %= y x = x % y
*= x *= y x = x * y
== equal to x == 5
=== equal value and equal type x === 5
!= not equal x != 5
!== not equal value or not equal type x !== 5

greater than x > 5
< less than x < 5
= greater than or equal to x >= 5
<= less than or equal to x <= 5

Types of loops in js?
While
Do while
For

Syntax :
While(condition)
{

(Increment, decrement)
}

do
{

(Increment, decrement)
} While (condition)

For(let i=0,i<5,i++){

}

Basic JavaScript Questionnaires

Sivakumar Mathiyalagan — Thu, 09 Apr 2026 17:35:23 +0000

What is JavaScript?

It is a High-level programming Language
Used to make webpages dynamic
It is a scripting language
It is Single threaded
It follows OOPs concept (Object-Oriented Programming)

High-level programming Language
A high-level programming language is a user-friendly, abstracted language designed for ease of use, enabling developers to write code in human-readable syntax

Used to make webpages dynamic
Normal a webpage with only HTML and CSS is of no use. In order to perform some operations or to make it interactive for the user, JavaScript need to be implemented along with HTML and CSS.

Scripting language
A scripting language is a programming language designed to automate the execution of tasks that would otherwise be executed one by one by a human operator
key features of scripting languages
Interpreted Execution: Scripting languages are typically interpreted rather than compiled.
(The code is executed line by line at runtime by a program called an interpreter, instead of being converted into a separate machine code file beforehand.)
Ease of Use: Scripting languages have simpler syntax, making them easier to learn, especially for beginners.
Dynamic Typing: Variables are typed at runtime, allowing more flexibility during execution.
Integration: Scripting languages are used to automate tasks by connecting and controlling different programs or system components.
High-Level Abstractions: They offer high-level features that simplify interaction with systems and applications.

Single threaded
JavaScript is a single-threaded language, meaning that it executes one operation at a time on a single thread. This characteristic is often misunderstood as a limitation, but JavaScript can still be non-blocking, which enables it to handle asynchronous operations(TBD) like reading from a file, fetching data from an API, or waiting for user input without blocking the main thread.

OOPs concept
features of Object-Oriented Programming
Encapsulation (TBD)
Abstraction (TBD)
Inheritance (TBD)
Polymorphism (TBD)

What are DataTypes?

Two types
Primitive and Non-Primitive

Primitive DataTypes

String
Number
Boolean
BigInt
Symbol
Null
Undefined

Non-Primitive

Object
Array
Functions
Date(TBD)
RegExp(TBD)

Feature	Primitive Data Types	Non-Primitive Data Types
Mutability	Values are immutable	Values are mutable
Data Complexity	Stores single, simple values	Stores complex or collection of values
Memory Storage	Stored by value	Stored by reference
Comparison	Compared by value	Compared by reference (two different objects are never equal even if content is same)
Memory Location	Stored in stack memory	Stored in heap memory

How to declare a variable?
Can be declared in four ways

Automatically without any keyword(not recommended)
Using var keyword(not recommended)
Using const keyword(recommended)
Using let keyword(recommended)

Automatically without any keyword
This allows to declare the same variable again and again which might lead to error so it is not recommended

Using var keyword

This was used till 2015 but it is also not recommended because this will also allow to initialize the same variable again and again
It is function scoped and doesnot provide block scope

const keyword
This is recommended if the value will not be changed in the future because if a variable is initialized with const key word then its value cannot be changed

let keyword
This is recommended if the value will be changed in the future

this provide block level scope for the variable unlike var

referrenced : https://www.w3schools.com/

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Basic Methods in Array

Sivakumar Mathiyalagan — Wed, 08 Apr 2026 16:02:20 +0000

Array.length This Method is used to find the length of the given array,its return type is number