200+ Full Stack Software Developer Interview Questions and Answers

Main concepts of OOP include encapsulation, inheritance, polymorphism, and abstraction.

• Encapsulation: Bundling data and methods that operate on the data into a single unit (object).

• Inheritance: Creating new classes based on existing classes, allowing for code reuse.

• Polymorphism: Objects of different classes can be treated as objects of a common superclass.

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

A Join is used to combine rows from two or more tables based on a related column between them.

• Types of Joins: Inner Join, Left Join, Right Join, Full Outer Join, Cross Join

• Inner Join: Returns rows when there is at least one match in both tables

• Left Join: Returns all rows from the left table and the matched rows from the right table

• Right Join: Returns all rows from the right table and the matched rows from the left table

• Full Outer Join: Returns rows when there is a match in on...read more

Hexaware is a global IT services company providing automation, cloud, and digital solutions.

• Hexaware was founded in 1990 and is headquartered in Mumbai, India.

• They offer services in areas such as application transformation, infrastructure management, and business process services.

• Hexaware has a strong focus on automation and digital technologies to help clients improve efficiency and innovation.

• The company has a global presence with offices in multiple countries including the...read more

MVC is a design pattern used in Java for separating concerns. Java has many design patterns like Singleton, Factory, etc.

• MVC separates Model, View, and Controller for better organization and maintenance

• Singleton ensures only one instance of a class is created

• Factory pattern creates objects without exposing the instantiation logic to the client

• Observer pattern allows objects to be notified of changes in other objects

• Decorator pattern adds functionality to an object dynamically

Yes, modern technologies are constantly evolving and I keep myself updated with the latest trends.

• I am familiar with cloud computing platforms like AWS, Azure, and Google Cloud

• I have experience with containerization using Docker and Kubernetes

• I am proficient in programming languages like Python, JavaScript, and Java

• I have worked with modern front-end frameworks like React and Angular

• I am familiar with DevOps practices and tools like Jenkins and Git

• I have knowledge of machine ...read more

RDBMS KERNEL is not a commonly used term in the industry.

• There is no widely accepted definition of RDBMS KERNEL.

• It may refer to the core components of a relational database management system.

• It could also be a term used by a specific company or product.

• Without more context, it is difficult to provide a specific answer.

Dependency injection is a design pattern where dependencies are provided to a class from the outside, while dependency inversion is a principle that states high-level modules should not depend on low-level modules, but both should depend on abstractions.

• Dependency injection is a technique to achieve dependency inversion.

• Dependency injection involves providing dependencies to a class from the outside, typically through constructor injection or setter injection.

• Dependency inver...read more

Triggers are events that initiate an action or set of actions. They are commonly used in databases and automation systems.

• Triggers are used in databases to automatically execute a set of actions when a certain event occurs, such as inserting or updating data.

• They can also be used in automation systems to initiate a process or workflow when a specific event occurs, such as receiving an email or a file upload.

• Triggers can be programmed to perform a variety of actions, such as s...read more

Shift all characters in a String 2 steps ahead in the alphabet.

• Create a mapping of each character to its corresponding shifted character.

• Iterate through each character in the input String and replace it with the shifted character.

• Handle edge cases such as wrapping around from 'z' to 'a'.

Optimizing API and rendering in React involves reducing unnecessary API calls, using memoization, lazy loading, and code splitting.

• Reduce unnecessary API calls by batching requests or using GraphQL to fetch only required data.

• Use memoization techniques like useMemo and useCallback to prevent unnecessary re-renders.

• Implement lazy loading for components that are not immediately needed, improving initial load time.

• Utilize code splitting to load only necessary code chunks, reduci...read more

Pair programming promotes collaboration, knowledge sharing, and code quality.

• Enhances code quality through immediate code review and feedback

• Promotes knowledge sharing and learning from each other

• Fosters collaboration and teamwork

• Reduces the likelihood of bugs and errors

• Increases productivity by leveraging two minds on the same problem

• Helps in breaking down complex problems into smaller tasks

• Improves communication skills within the team

Pipes in Angular are used for transforming data in templates.

• Pipes are used to format data before displaying it in the view.

• They can be used to filter, sort, or transform data in various ways.

• Examples include currency, date, uppercase, and lowercase pipes.

Java is a popular backend language, polymorphism allows objects to be treated as instances of their parent class, reverse string by iterating through characters.

• Java is commonly used in backend development for its robustness and scalability.

• Polymorphism in OOP allows objects to be treated as instances of their parent class, enabling flexibility and reusability.

• To reverse a string, iterate through the characters from the end to the beginning and append them to a new string.

Promise is a one-time event while Observable can emit multiple values over time.

• Promise is used for asynchronous operations that will return a single value or an error.

• Observable is used for asynchronous operations that can return multiple values over time.

• Promise can be in one of three states: pending, fulfilled, or rejected.

• Observable can emit values, errors, and completion events.

• Promise can be converted to an Observable using the from() method in RxJS.

• Observable can be co...read more

Shallow DOM is a subset of the Virtual DOM that represents a single level of the component tree.

• Shallow DOM is a lightweight representation of the Virtual DOM.

• It only includes the top-level elements of a component tree.

• Virtual DOM is a complete representation of the component tree.

• It includes all the elements and their properties.

• Virtual DOM is used to optimize rendering performance.

• Shallow rendering is used for unit testing components.

DML is provided to manipulate data in a database.

• DML stands for Data Manipulation Language.

• It is used to insert, update, delete, and retrieve data from a database.

• DML commands include INSERT, UPDATE, DELETE, and SELECT.

• DML is essential for managing and maintaining data in a database.

Count the number of alphabets, numbers, and special characters in a given input.

• Iterate through each character in the input string

• Use regular expressions to check if the character is an alphabet, number, or special character

• Increment respective counters based on the character type

ORM tool is used to map object-oriented programming language to a relational database management system.

• ORM tool helps in reducing the amount of code required to interact with the database.

• It provides an abstraction layer between the application and the database.

• ORM tool helps in managing the database schema and relationships between tables.

• It allows developers to work with objects instead of SQL statements.

• Examples of ORM tools include Hibernate, Entity Framework, and Django...read more

MVVM is a software architecture pattern that separates the user interface from the business logic.

• MVVM stands for Model-View-ViewModel

• Model represents the data and business logic

• View represents the user interface

• ViewModel acts as a mediator between the View and Model

• ViewModel exposes data and commands to the View

• MVVM is used to improve code maintainability, testability, and separation of concerns

Create a generic method to add string or integer to List or List

• Create a generic method that takes a List and an element as input

• Use Java generics to specify the type of List and element

• Check the type of List and element, then add the element to the List

Implemented E-Commerce website using HTML, CSS, JavaScript, and backend technologies like Node.js and MongoDB.

• Used HTML and CSS for front-end design and layout.

• Implemented interactive features using JavaScript.

• Utilized Node.js for server-side scripting and handling backend logic.

• Stored and managed data using MongoDB database.

• Implemented payment gateway integration for secure transactions.

Code to generate Excel sheet column names

• Use ASCII code to generate column names

• Start with 'A' and increment by 1 for each column

• Use a loop to generate multiple column names

Serialisation is the process of converting an object into a format that can be easily stored or transmitted. Externalisation is a way to customize the serialization process. Serializable is an interface in Java that allows objects to be serialized.

• Serialisation is the process of converting an object into a format that can be easily stored or transmitted

• Externalisation is a way to customize the serialization process

• Serializable is an interface in Java that allows objects to be...read more

A data dictionary in ABAP is a centralized repository for data definitions used in SAP systems.

• It contains metadata about tables, fields, data elements, domains, and structures.

• Data dictionary objects are used to define the structure of database tables and to ensure data integrity.

• It helps in maintaining consistency of data across the system and simplifies development and maintenance tasks.

• Example: SE11 transaction in SAP is used to access and maintain data dictionary objects...read more

My favorite food is pizza.

• I love the combination of crispy crust, tangy tomato sauce, and melted cheese.

• There are endless topping options to customize the pizza to my liking.

• It's a versatile food that can be enjoyed for lunch, dinner, or even as a late-night snack.

• Pizza is a popular choice for gatherings and parties, bringing people together.

• Some of my favorite pizza toppings include pepperoni, mushrooms, and olives.

Class is a blueprint for objects while Interface defines a contract for classes to implement.

• Class can have both properties and methods while Interface only has method signatures.

• Class can be instantiated while Interface cannot be instantiated.

• Class can inherit from another class while Interface can only be implemented by a class.

• Class can have access modifiers while Interface methods are public by default.

• Example: Class - Animal, Interface - Flyable

var is function scoped, let is block scoped, const is block scoped and cannot be reassigned.

• var is function scoped, let is block scoped, const is block scoped and cannot be reassigned

• var can be redeclared and updated, let can be updated but not redeclared, const cannot be redeclared or updated

• Example: var x = 10; let y = 20; const z = 30;

Class-based components are ES6 classes that extend React.Component, while function-based components are functions that return JSX.

• Class-based components are more feature-rich and have access to lifecycle methods.

• Function-based components are simpler and easier to read and test.

• Class-based components can have state and use lifecycle methods like componentDidMount and componentDidUpdate.

• Function-based components can use React hooks to manage state and lifecycle.

• Class-based comp...read more

Elements in an array can be accessed by using their index positions.

• Access elements by specifying the index position within square brackets, starting from 0.

• For example, to access the first element in an array named 'colors': colors[0] will give the first element.

• Loop through the array to access all elements sequentially.

Elements can be deleted from an array using various methods like splice(), pop(), shift(), and filter().

• Use splice() method to delete elements by index

• Use pop() method to remove the last element

• Use shift() method to remove the first element

• Use filter() method to create a new array without the elements to be deleted

Yes, I can build an app with the given specification.

• I have experience in full stack development and can handle both front-end and back-end tasks.

• I am proficient in programming languages like JavaScript, HTML, CSS, and frameworks like React and Node.js.

• I have worked on similar projects before and can provide examples if needed.

Websites work by combining front-end and back-end technologies to create interactive user experiences. Functionality is added through coding and integrating various features.

• Websites work by using HTML, CSS, and JavaScript for front-end development.

• Functionality is added through back-end technologies like Node.js, Python, or Ruby on Rails.

• Database management systems like MySQL or MongoDB are used to store and retrieve data.

• APIs are integrated to connect with external services...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

var is function-scoped while let is block-scoped in JavaScript.

• var keyword is function-scoped, meaning it is accessible throughout the function it is declared in.

• let keyword is block-scoped, meaning it is only accessible within the block it is declared in.

• Using var can lead to variable hoisting issues, while let provides more predictable behavior.

• let allows for better variable scoping and reduces the risk of unintended variable redeclarations.

I use a combination of manual testing, unit testing, and debugging tools to identify bugs in my code.

• Perform manual testing by running the code and checking for any unexpected behavior or errors.

• Write unit tests to verify the functionality of individual components and catch any issues early on.

• Utilize debugging tools like breakpoints, logging, and stack traces to track down the root cause of bugs.

• Collaborate with team members to review code and identify potential issues throu...read more

Form control build refers to the process of creating and customizing form controls in web development.

• Form controls are elements like text boxes, radio buttons, and dropdown menus that allow users to input data on a website.

• Developers can use HTML, CSS, and JavaScript to build and style form controls to fit the needs of their website or application.

• Form control build also involves adding validation and error handling to ensure that user input is accurate and secure.

Table variables are created in memory and are scoped to the batch, while temporary tables are stored in tempdb and can be accessed across batches.

• Table variables are created using DECLARE statement, while temporary tables are created using CREATE TABLE statement.

• Table variables are limited to the scope of the batch or stored procedure in which they are declared, while temporary tables can be accessed across batches.

• Table variables are automatically deallocated when the batch ...read more

JDBC is a Java API for connecting to databases. Spring Boot provides auto-configuration for JDBC.

• JDBC stands for Java Database Connectivity.

• It is a Java API for connecting to databases.

• Spring Boot provides auto-configuration for JDBC, making it easy to set up database connections.

• JDBC can be used to execute SQL statements and retrieve results.

• Example: DriverManager.getConnection(url, username, password);

Use Linq query to filter data and group by in C#

• Use 'Where' method to filter data based on a condition

• Use 'GroupBy' method to group the filtered data based on a key

• Example: var result = data.Where(x => x.Property == value).GroupBy(x => x.GroupKey)

Liskov Substitution Principle states that objects of a superclass should be replaceable with objects of its subclasses without affecting the program's correctness.

• Subtypes must be substitutable for their base types.

• Derived classes should be able to extend the functionality of base classes without changing their behavior.

• Violating this principle can lead to unexpected behavior in the program.

• Example: If a Square class inherits from a Rectangle class, it should be able to subst...read more

String manipulation using primitive data types in a program

• Use string concatenation to combine multiple strings

• Use string comparison to check for equality or order

• Use string slicing to extract substrings

Spring is a framework for building Java applications, while Spring Boot is an extension that simplifies the setup and development of Spring applications.

• Spring is a comprehensive framework that provides infrastructure support for developing Java applications.

• Spring Boot is an extension of the Spring framework that simplifies the setup and development of Spring applications by providing defaults for configuration.

• Spring Boot includes embedded servers, which means you can run y...read more

Design a form and store data in a database.

• Create a form with input fields for relevant data

• Use a server-side language like PHP to handle form submission

• Connect to a database and create a table to store the data

• Insert the submitted data into the database table

Take two numbers as input and display their sum

• Create a function that takes two numbers as input

• Add the two numbers together to get the sum

• Return the sum as output

Yes, applications can be made using C# code.

• C# is a versatile programming language commonly used for developing applications.

• C# can be used to create web applications, desktop applications, mobile apps, and more.

• Popular frameworks like .NET and Xamarin support C# for application development.

Authentication is the process of verifying the identity of a user, while authorization determines what resources a user can access.

• Authentication is the process of verifying the identity of a user.

• Authorization determines what resources a user can access.

• In Node.js, authentication and authorization can be implemented using various libraries and techniques such as Passport.js, JSON Web Tokens (JWT), and role-based access control (RBAC).

• Authentication can be done using strategi...read more

Different rendering methods in Next.js include Server-side rendering (SSR), Static Site Generation (SSG), and Incremental Static Regeneration (ISR).

• Server-side rendering (SSR) - Renders the page on each request, providing the most up-to-date content.

• Static Site Generation (SSG) - Generates HTML at build time and serves it to the client, improving performance.

• Incremental Static Regeneration (ISR) - Allows for regeneration of static pages on-demand without rebuilding the entire...read more