30+ HP Rajyaguru Interview Questions and Answers

let is block scoped, const is immutable, var is function scoped

• let: block scoped, can be reassigned

• const: block scoped, cannot be reassigned, but properties of objects can be changed

• var: function scoped, can be reassigned

Map applies a function to each element of an array and returns a new array, while forEach iterates over each element without returning a new array.

• Map returns a new array with the results of applying a function to each element of the original array.

• forEach simply iterates over each element of the array without returning a new array.

• Example: Using map to double each element in an array - [1, 2, 3].map(num => num * 2) would return [2, 4, 6].

• Example: Using forEach to log each el...read more

ES6 features are new additions to JavaScript introduced in ECMAScript 2015.

• Arrow functions

• Let and const declarations

• Template literals

• Destructuring assignments

• Classes

• Promises

• Modules

Program to sort an array of strings

• Use a sorting algorithm like bubble sort, selection sort, or merge sort

• Iterate through the array and compare adjacent elements to sort them

• Ensure the sorting algorithm is efficient and handles edge cases

Overloading is having multiple methods in the same class with the same name but different parameters. Overriding is having a method in a subclass with the same name and parameters as a method in the superclass.

• Overloading is resolved at compile time based on the method signature, while overriding is resolved at runtime based on the object type.

• Overloading is used to provide different implementations of a method based on the input parameters, while overriding is used to provid...read more

Encapsulation is achieved by restricting access to certain components of an object and only allowing access through designated methods.

• Use access modifiers like private, protected, and public to control access to class members

• Create getter and setter methods to access and modify private variables

• Encapsulate related data and methods within a class to ensure data integrity

Hoisting is a JavaScript mechanism where variable and function declarations are moved to the top of their containing scope during compilation.

• Variable and function declarations are hoisted to the top of their scope.

• Only declarations are hoisted, not initializations.

• Function declarations take precedence over variable declarations.

• Hoisting can lead to unexpected behavior if not understood properly.

String is immutable in order to ensure data integrity and security.

• Immutable strings prevent accidental changes to data, ensuring data integrity.

• Immutable strings allow for more efficient memory management and optimization.

• Immutable strings help prevent security vulnerabilities such as injection attacks.

• Example: In Java, once a string object is created, its value cannot be changed.

An arrow function is a concise way to write functions in JavaScript.

• Arrow functions are written using the '=>' syntax.

• They do not have their own 'this' keyword.

• They are often used for short, one-line functions.

• Example: const add = (a, b) => a + b;

Spring Boot is a framework that simplifies the development of Java applications by providing pre-configured settings and tools.

• Spring Boot eliminates the need for manual configuration by providing defaults for most settings.

• It allows developers to quickly set up and run standalone Spring-based applications.

• Spring Boot includes embedded servers like Tomcat, Jetty, or Undertow for easy deployment.

• It promotes convention over configuration, reducing the amount of boilerplate code...read more

Filter files ending with amazon.txt in Unix shell

• Use the 'ls' command to list all files in the directory

• Use the 'grep' command to filter files ending with 'amazon.txt'

• Combine the two commands using a pipe '|' symbol

Regression testing is the process of retesting modified software to ensure that the existing functionalities are not affected.

• It is performed after making changes to the software to identify any new defects or regression bugs.

• It helps in ensuring that the previously working features are still functioning correctly.

• Regression test cases are typically derived from the existing test cases.

• It can be performed manually or using automated testing tools.

• Examples: retesting a bug fix...read more

Find common sub-strings in two strings and print them in alphabetical order.

• Use a nested loop to compare each character of both strings.

• Store common sub-strings in an array.

• Sort the array in alphabetical order.

• Print the sorted array.

List of test scenarios for mobile app release

• Functional testing of all features

• Usability testing for ease of use

• Compatibility testing on different devices and OS versions

• Performance testing for speed and responsiveness

• Security testing for data protection

• Localization testing for language and cultural differences

• Regression testing to ensure no new bugs introduced

• Accessibility testing for users with disabilities

Java program to find occurrences of characters in a string

• Create a HashMap to store characters and their counts

• Iterate through the string and update the counts in the HashMap

• Print the characters and their counts from the HashMap

Object-oriented programming is a programming paradigm based on the concept of objects, which can contain data and code.

• Encapsulation: Objects can encapsulate data and behavior within a single unit.

• Inheritance: Objects can inherit attributes and methods from other objects.

• Polymorphism: Objects can take on different forms or have multiple behaviors.

• Example: Classes in Java or C++ are used to create objects with properties and methods.

To read an external text file, you can use file handling techniques in programming languages like Python or Java.

• Use file handling functions like open(), read(), and close() in Python to read an external text file.

• In Java, use classes like FileReader and BufferedReader to read text files.

• Specify the file path and mode (read mode) when opening the file.

• Read the contents of the file line by line or as a whole, depending on the requirements.

• Close the file after reading to releas...read more

Retesting is the process of executing tests that have previously failed to verify if the reported defects have been fixed.

• Retesting is done to ensure that the defects found in the previous test cycle have been resolved.

• It involves rerunning the failed test cases or executing the specific steps that caused the failure.

• Retesting is typically performed after the defects have been fixed and before regression testing.

• The focus of retesting is on the specific areas that were previo...read more

Normalization is the process of organizing data in a database to reduce redundancy and improve data integrity.

• Normalization is used to eliminate data redundancy by breaking up tables into smaller tables and defining relationships between them.

• It helps in reducing data anomalies such as insertion, update, and deletion anomalies.

• Normalization is achieved through a series of normal forms (1NF, 2NF, 3NF, BCNF, etc.)

• For example, in a database of students and courses, instead of st...read more

SDLC stands for Software Development Life Cycle, which is a process used to design, develop, and test software.

• SDLC is a framework that outlines the steps involved in software development.

• It includes planning, designing, coding, testing, and maintenance.

• Each phase of SDLC has its own set of deliverables and objectives.

• SDLC models include Waterfall, Agile, and DevOps.

• The choice of SDLC model depends on the project requirements and team's preference.

STLC stands for Software Testing Life Cycle, which is a process followed to ensure software quality.

• STLC involves planning, designing, executing, and reporting of tests.

• It includes various phases such as requirement analysis, test planning, test design, test execution, and test closure.

• The main objective of STLC is to ensure that the software meets the specified requirements and is of high quality.

• STLC helps in identifying defects early in the development cycle, which reduces...read more

let, const, and var are JavaScript keywords used to declare variables with different scoping rules.

• let and const are block-scoped variables introduced in ES6, while var is function-scoped.

• let allows reassignment, while const is a constant that cannot be reassigned.

• Hoisting is a JavaScript behavior where variable and function declarations are moved to the top of their scope.

• Closure is a combination of a function and the lexical environment within which that function was declar...read more

Spring is a lightweight framework for building enterprise applications in Java.

• Provides comprehensive infrastructure support for developing Java applications

• Facilitates easier configuration and integration of various components

• Promotes good programming practices like dependency injection and aspect-oriented programming

• Includes modules like Spring Core, Spring MVC, Spring Security, etc.

• Example: @Autowired annotation for dependency injection

Sanity testing is a subset of regression testing, while smoke testing is a subset of acceptance testing.

• Sanity testing is performed to ensure that the critical functionalities of the software are working as expected.

• Smoke testing is performed to verify if the software build is stable enough for further testing.

• Sanity testing is usually performed after major changes or bug fixes.

• Smoke testing is performed on each build to identify critical issues early in the development cycle...read more

Threads of javascript refer to the concept of asynchronous programming in JavaScript. Architecture in this context likely refers to the overall structure and organization of a React Native application.

• JavaScript is single-threaded, meaning it can only execute one piece of code at a time. Asynchronous programming allows for non-blocking operations, improving performance and user experience.

• React Native architecture typically follows a component-based structure, where different...read more

A framework is a set of guidelines, libraries, and tools that help in developing and testing software applications.

• Provides structure and guidelines for developing software

• Includes libraries and tools to simplify development tasks

• Promotes code reusability and maintainability

• Examples: Selenium WebDriver for web automation testing, TestNG for test execution and reporting

My automation framework is based on the Page Object Model design pattern, utilizing TestNG for test execution and reporting.

• Utilizes Page Object Model design pattern for better code organization and maintenance

• Uses TestNG for test execution and reporting

• Employs data-driven testing for better test coverage

• Integration with CI/CD tools like Jenkins for continuous testing

• Utilizes Selenium WebDriver for browser automation

API Gateway is a server that acts as an API front-end, receiving API requests, enforcing throttling and security policies, passing requests to the back-end service, and then passing the response back to the requester.

• API Gateway acts as a single entry point for all client requests to the backend services.

• It can handle tasks like authentication, authorization, rate limiting, caching, and request/response transformations.

• Examples of API Gateways include Amazon API Gateway, Apig...read more

Bug life cycle is the process of a bug from identification to resolution.

• Bug is identified by tester

• Bug is logged in bug tracking tool

• Bug is assigned to developer

• Developer fixes the bug

• Bug is retested by tester

• Bug is closed if fixed or reopened if not

Object-oriented programming concepts that focus on data encapsulation, inheritance, polymorphism, and abstraction.

• Encapsulation: bundling data and methods that operate on the data into a single unit (class)

• Inheritance: allows a class to inherit properties and behavior from another class

• Polymorphism: ability for objects of different classes to respond to the same message

• Abstraction: hiding the complex implementation details and showing only the necessary features