Infosys Associate Consultant Interview Questions, Process, and Tips

Array list and linked list are both data structures used to store and manipulate collections of elements.

• Array list is implemented using an array, while linked list is implemented using nodes that are linked together.

• Array list allows for fast access to elements by index, but slower insertion and deletion operations.

• Linked list allows for fast insertion and deletion operations, but slower access to elements by index.

• Ar...read more

Abstract classes are classes that cannot be instantiated and can have both abstract and non-abstract methods. Interfaces are a collection of abstract methods.

• Abstract classes can have instance variables, constructors, and non-abstract methods.

• Interfaces can only have static final variables and abstract methods.

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

• Abstract classes are used whe...read more

A controller is responsible for handling HTTP requests and returning responses, while a RestController is specifically designed for RESTful web services.

• A controller can handle various types of requests, including non-RESTful ones, while a RestController is limited to handling RESTful requests.

• A RestController automatically serializes and deserializes request and response bodies to and from JSON, while a controller req...read more

Java 8 introduced several new features including lambda expressions, functional interfaces, and stream API.

• Lambda expressions allow writing concise and functional code.

• Functional interfaces enable the use of lambda expressions.

• Stream API provides a powerful way to process collections of data.

• Default methods allow adding new methods to existing interfaces.

• Optional class helps to handle null values more effectively.

• Date ...read more

String, StringBuffer, and StringBuilder are classes in Java used for manipulating strings.

• String is immutable, meaning its value cannot be changed once it is created.

• StringBuffer is mutable and thread-safe, making it suitable for multi-threaded environments.

• StringBuilder is also mutable but not thread-safe, providing better performance in single-threaded scenarios.

REST APIs are a set of rules and conventions for building web services, while annotations are metadata used to provide additional information to the code.

• REST APIs are a way to design and implement web services that follow the principles of Representational State Transfer (REST).

• They use HTTP methods like GET, POST, PUT, DELETE to perform operations on resources.

• Annotations are used in programming languages like Java t...read more

Comparator is an interface used to compare objects, while Comparable is an interface used to define a natural ordering of objects.

• Comparator is used when the natural ordering of objects needs to be overridden or when comparing objects of different classes.

• Comparable is used when the natural ordering of objects is based on a single property or when comparing objects of the same class.

• Example: Comparator can be used to s...read more

Final is an adjective meaning last or ultimate, finally is an adverb meaning at last or in the end, finalyse is not a valid English word.

• Final is used to describe something that is last or ultimate, such as a final decision or final exam.

• Finally is used to indicate that something is happening at last or in the end, such as finally reaching a destination after a long journey.

• Finalyse is not a valid English word and shou

JPA stands for Java Persistence API, a Java specification for accessing, persisting, and managing data between Java objects and a relational database.

• JPA is a Java specification for ORM (Object-Relational Mapping)

• It provides a way to map Java objects to database tables and vice versa

• JPA simplifies database operations by abstracting the underlying SQL queries

• Entities in JPA represent tables in the database

• JPA supports v...read more

Objects can be created in programming languages using constructors, classes, object literals, and factory functions.

• Using constructors in object-oriented programming languages like Java

• Defining classes and instantiating objects in languages like C++ and Python

• Creating object literals in JavaScript

• Using factory functions to create objects in languages like TypeScript

Spring Security is a powerful and customizable authentication and access control framework for Java applications.

• Add Spring Security dependency in pom.xml

• Configure security settings in SecurityConfig class

• Use annotations like @EnableWebSecurity and @EnableGlobalMethodSecurity

• Define user roles and permissions in UserDetailsServiceImpl

• Secure endpoints using @PreAuthorize or @Secured annotations

Virtual DOM is a lightweight copy of the actual DOM in React, used for efficient updates.

• Virtual DOM is a concept where a lightweight copy of the actual DOM is created in memory.

• When changes are made to the virtual DOM, React compares it with the actual DOM to identify the differences.

• React then updates only the necessary parts of the actual DOM, making the process more efficient.

• This helps in improving performance by ...read more

JSX is a syntax extension for JavaScript that allows writing HTML elements in JavaScript code.

• JSX makes it easier to write and manage UI components in React

• It allows mixing HTML and JavaScript in a single file

• JSX gets transpiled into regular JavaScript by tools like Babel