VTS Group Interview Questions and Answers

Java 17 introduces sealed classes to restrict inheritance and improve code maintainability.

• Sealed classes are declared using the 'sealed' keyword followed by the permitted subclasses.

• Subclasses of a sealed class must be either final or sealed themselves.

• Errors may occur when trying to extend a sealed class with a non-permitted subclass.

Implementation of 'notify me if item is back in stock' feature in an ecommerce application

• Create a database table to store user notifications for out-of-stock items

• Implement a service to check item availability and send notifications to subscribed users

• Provide a user interface for users to subscribe to notifications for specific items

SOLID principles are a set of five design principles to make software more maintainable, scalable, and flexible.

• S - Single Responsibility Principle: A class should have only one reason to change.

• O - Open-Closed Principle: Software entities should be open for extension but closed for modification.

• L - Liskov Substitution Principle: Subtypes must be substitutable for their base types.

• I - Interface Segregation Principle: A client should not be forced to implement interfaces they ...read more

Java 8 introduced several new features including lambda expressions, streams, and default methods.

• Lambda expressions allow for functional programming and simplify code.

• Streams provide a way to process collections of data in a functional way.

• Default methods allow for adding new methods to interfaces without breaking existing implementations.

• Other features include the Date and Time API, Nashorn JavaScript engine, and improved security.

• Java 8 also introduced the concept of Optio...read more

Spring is a framework that provides comprehensive infrastructure support, while Spring Boot is a tool that simplifies Spring application development.

• Spring is a comprehensive framework that provides various modules for different functionalities like Spring MVC, Spring Security, Spring Data, etc.

• Spring Boot is a tool that simplifies the setup and configuration of Spring applications by providing defaults and auto-configuration.

• Spring Boot reduces the need for manual configurat...read more