30+ Senior Member Technical Interview Questions and Answers

Docker is a containerization platform while Virtual Machine is a virtualization platform.

• Docker shares the host OS kernel while VM has its own OS.

• Docker is lightweight and faster to start than VM.

• Docker containers are portable and can run on any system with Docker installed.

• VMs are more secure as they provide complete isolation from the host system.

• Docker is ideal for microservices architecture while VMs are better for running multiple applications with different OS requireme...read more

String Pool is a cache of String objects. Strings are immutable because their values cannot be changed once created.

• String Pool is a memory area where Java stores String objects to save memory.

• When a new String is created, Java first checks if it already exists in the String Pool. If it does, it returns a reference to the existing object instead of creating a new one.

• Strings are immutable because any operation that modifies a String actually creates a new String object rather...read more

Optimizing SQL queries can improve performance and reduce resource usage.

• Use indexes to speed up data retrieval

• Avoid using SELECT * and instead specify only required columns

• Use JOINs instead of subqueries

• Avoid using functions in WHERE clauses

• Use UNION ALL instead of UNION if possible

• Avoid using temporary tables

• Use EXPLAIN to analyze query performance

ADP is a global provider of cloud-based human capital management solutions that streamline HR, payroll, talent, time, tax and benefits administration.

• ADP provides software and services related to human resource management, payroll processing, tax compliance, and benefits administration

• It offers cloud-based solutions for businesses of all sizes

• ADP's domain is human capital management

• It serves clients in over 140 countries worldwide

• Some of its popular products include ADP Workf...read more

The problem involves finding the minimum steps to delete a substring comprising of same characters from a given string.

• Use dynamic programming to keep track of the minimum steps required to delete substrings.

• Iterate through the string and check for substrings with same characters.

• Update the DP array with the minimum steps required to delete the substring.

Linked List allows dynamic size, efficient insertion/deletion, while Array List has faster access and better cache locality.

• Linked List can grow or shrink dynamically, while Array List has fixed size.

• Insertion and deletion are faster in Linked List as it requires only changing pointers, while Array List requires shifting elements.

• Linked List has better memory utilization as it only allocates memory when needed, while Array List pre-allocates memory.

• Array List has faster acces...read more

Program to return square of integers in ascending order from input array

• Iterate through the input array and calculate the square of each integer

• Store the squares in a new array and sort it in ascending order

• Return the sorted array of squares

An API is a set of rules and protocols that allows different software applications to communicate with each other.

• API stands for Application Programming Interface

• It defines the methods and data formats that applications can use to request and exchange information

• APIs can be used to access services or data from other applications or platforms

• Examples include Google Maps API for integrating maps into a website, Twitter API for accessing tweets, and Spotify API for music streami...read more

Abstract class can have both abstract and non-abstract methods, while interface can only have abstract methods.

• Abstract class can have constructors, fields, and methods, while interface cannot have any implementation.

• A class can implement multiple interfaces but can only inherit from one abstract class.

• Abstract classes are used to define a common base class for related classes, while interfaces are used to define a contract for classes to implement.

• Example: Abstract class 'Sh...read more

The web works by using a client-server model where clients request and receive information from servers via the internet.

• Clients (such as web browsers) send requests for web pages or resources to servers

• Servers process these requests and send back the requested information

• HTTP (Hypertext Transfer Protocol) is commonly used for communication between clients and servers

• Web pages are typically written in HTML (Hypertext Markup Language) and styled with CSS (Cascading Style Sheet...read more

Monolith has simplicity but lacks scalability, while microservices offer flexibility but introduce complexity.

• Monolith: Simplicity in development and deployment, easier to debug and test

• Monolith: Lack of scalability, all components tightly coupled

• Microservices: Flexibility to use different technologies for different services

• Microservices: Scalability, each service can be independently scaled

• Microservices: Increased complexity in managing multiple services and communication be...read more

Find the second highest occurrence of a vowel in a string.

• Iterate through the string and count the occurrences of each vowel (a, e, i, o, u).

• Store the counts in an array and find the second highest count.

• Return the vowel with the second highest count.

SDLC process for HR ERP implementation involves planning, analysis, design, development, testing, deployment, and maintenance.

• Planning phase involves defining project scope, goals, and objectives.

• Analysis phase involves gathering requirements and analyzing existing systems.

• Design phase involves creating a blueprint for the new system.

• Development phase involves coding and building the system.

• Testing phase involves testing the system for bugs and errors.

• Deployment phase involve...read more

There are 7 layers in the OSI model: Physical, Data Link, Network, Transport, Session, Presentation, and Application.

• Physical layer deals with physical connections and signals

• Data Link layer handles error detection and correction

• Network layer routes data between different networks

• Transport layer ensures data delivery and error checking

• Session layer establishes, maintains, and terminates connections

• Presentation layer translates data into a format that the application layer can...read more

Resources are tools or assets used to achieve a goal, while styles refer to the way in which something is done or presented.

• Resources can include materials, equipment, personnel, or financial assets.

• Styles can encompass different approaches, methods, techniques, or aesthetics.

• For example, in software development, resources may include programming languages and libraries, while styles may refer to coding conventions and design patterns.

An abstract class is a class that cannot be instantiated and may contain abstract methods.

• Cannot be instantiated directly

• May contain abstract methods that must be implemented by subclasses

• Can have both abstract and non-abstract methods

• Used to define a common interface for subclasses

Use a web scraping tool to count the number of links on a web page.

• Use a web scraping tool like BeautifulSoup in Python or Selenium to extract all the links from the HTML of the web page.

• Count the number of link elements or anchor tags in the HTML.

• Consider different types of links such as internal links, external links, and anchor links.

• Handle cases where links are dynamically loaded or hidden behind JavaScript.

• Verify the accuracy of the count by manually checking a sample of...read more

Use CSS selector to locate element on webpage

• Use unique id or class names to locate element

• Use CSS selectors like 'id', 'class', 'name', 'tag name', etc.

• Use XPath if necessary for complex element locating

Find the largest string in a given array of strings

• Iterate through the array and compare the length of each string to find the largest one

• Use a variable to keep track of the largest string found so far

• Return the largest string at the end

The most used technologies during work include Java, Spring Boot, AWS, Docker, and Kubernetes.

• Java

• Spring Boot

• AWS

• Docker

• Kubernetes

Lock and Synchronised are both mechanisms used for thread synchronization in Java.

• Lock is a more flexible and powerful mechanism compared to synchronized keyword in Java.

• Lock interface provides more functionalities like tryLock(), lockInterruptibly(), etc.

• Lock allows for more fine-grained control over locking and unlocking of resources.

• Synchronized keyword is simpler to use but may lead to deadlocks in complex scenarios.

• Synchronized keyword is implicitly used in synchronized ...read more

Remove zeros from arrays list of strings

• Iterate through each string in the array

• Use filter method to remove zeros from each string

• Return the updated array without zeros

FindElements method returns a list of web elements matching the specified locator.

• Return type of FindElements is List

• It returns a list of all elements matching the specified locator

• Example: List elements = driver.findElements(By.xpath("//input[@type='text']"));

Design a 1:1 chat feature for seamless communication between two users.

• Implement real-time messaging functionality

• Include features like read receipts, typing indicators, and message timestamps

• Allow users to share multimedia content such as images and videos

• Provide options for users to customize their chat settings and notifications

OOPs (Object-Oriented Programming) is a programming paradigm based on the concept of objects, which can contain data and code.

• OOPs focuses on creating objects that interact with each other to solve complex problems

• Key principles include encapsulation, inheritance, polymorphism, and abstraction

• Encapsulation allows data hiding and bundling of data with methods that operate on that data

• Inheritance enables a new class to inherit properties and behavior of an existing class

• Polymor...read more

Redux is a predictable state container for JavaScript apps.

• Redux is a state management library for JavaScript applications.

• It helps in managing the state of an application in a predictable way.

• Redux stores the entire state of an application in a single immutable object.

• Actions are dispatched to update the state in Redux.

• Reducers specify how the state should change in response to an action.

• Redux is commonly used with React to manage the state of React components.

Red bus high level design

• Design a system for booking and managing bus tickets

• Include features like searching for buses, selecting seats, and making payments

• Consider scalability, availability, and security in the design

• Use a distributed architecture with load balancing and fault tolerance

• Implement a database for storing bus schedules, seat availability, and user information

A framework is a structure that provides guidelines, best practices, and reusable components for developing software applications.

• Framework helps in organizing code and promoting code reusability.

• It provides a set of libraries, tools, and APIs to facilitate development.

• Frameworks can be front-end (e.g. React, Angular) or back-end (e.g. Spring, Django).

• Examples of frameworks include Ruby on Rails, Laravel, and .NET Framework.

Traversal in matrix is the process of visiting each element in a matrix in a specific order.

• Traversal can be done in different orders such as row-wise, column-wise, spiral, etc.

• For example, in a 3x3 matrix, row-wise traversal would be [1, 2, 3, 4, 5, 6, 7, 8, 9].

• Spiral traversal in the same matrix would be [1, 2, 3, 6, 9, 8, 7, 4, 5].

Design a parking lot with efficient layout and features

• Consider the size and layout of the parking lot

• Include designated spots for different types of vehicles (compact, regular, handicapped)

• Implement a clear signage system for easy navigation

• Incorporate security measures such as lighting and surveillance cameras

• Include payment options for parking fees (e.g. ticket machines, mobile app)

• Consider environmental factors like drainage and green spaces