DRS Knowledge city Interview Questions and Answers

Various annotations are used in Spring Boot for different purposes.

• 1. @RestController - Used to define RESTful web services.

• 2. @RequestMapping - Maps web requests to specific handler methods.

• 3. @Autowired - Injects dependencies into a Spring bean.

• 4. @Component - Indicates a class is a Spring component.

• 5. @Service - Indicates a class is a Spring service.

• 6. @Repository - Indicates a class is a Spring repository.

• 7. @Configuration - Indicates a class contains Spring configuration...read more

Annotations in Spring Boot are used to provide metadata and configuration to the application.

• Annotations are used to define the behavior of various components in a Spring Boot application.

• They can be used to configure dependency injection, define request mappings, handle exceptions, etc.

• Some commonly used annotations in Spring Boot include @RestController, @Autowired, @RequestMapping, @ExceptionHandler, etc.

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 boilerplate code and increasin...read more

Multi Threading is the ability of a CPU to execute multiple threads concurrently, allowing for better performance and responsiveness.

• Allows multiple tasks to run concurrently within a single process

• Improves performance by utilizing CPU resources efficiently

• Can lead to synchronization issues if not handled properly

• Examples: running multiple tasks simultaneously in a web server, processing data in parallel

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

• OOPs focuses on creating objects that interact with each other to solve a problem.

• Key principles of OOPs include Inheritance, Encapsulation, Polymorphism, and Abstraction.

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

• Encapsulation involves bundling data and methods that ...read more

A stack is a data structure that follows the Last-In-First-Out (LIFO) principle.

• Elements are added and removed from the top of the stack.

• Common operations include push (add element) and pop (remove element).

• Stacks are used in function calls, undo/redo functionality, and expression evaluation.

Polymorphism is the ability of an object to take on many forms, allowing objects of different classes to be treated as the same type.

• Polymorphism allows objects to be used interchangeably with other objects of the same superclass.

• It enables code reusability and flexibility in object-oriented programming.

• Polymorphism can be achieved through method overriding and method overloading.

• Example: A superclass 'Animal' with subclasses 'Dog' and 'Cat'. Both 'Dog' and 'Cat' can be treat...read more

RestTemplate is a class in Spring Framework that simplifies making HTTP requests and handling responses.

• RestTemplate is part of the Spring Web module.

• It provides methods to send HTTP requests and receive responses.

• It supports various HTTP methods like GET, POST, PUT, DELETE, etc.

• RestTemplate can handle different data formats like JSON, XML, etc.

• It can be used to consume RESTful APIs and interact with external services.

• Example: RestTemplate restTemplate = new RestTemplate();