Top 100 Spring Boot Interview Questions and Answers

Stereotype annotations in Spring Boot are used to define custom annotations for specific use cases.

• Stereotype annotations are used to group related components and simplify configuration.

• Examples include @Controller, @Service, and @Repository.

• Custom stereotype annotations can be created using @Component and @Stereotype.

• Stereotype annotations can be used with other Spring annotations like @Autowired and @Qualifier.

Bean annotation is used in Spring Boot on class or method to indicate that a method produces a bean to be managed by the Spring container.

• Bean annotation is used on methods within a class to indicate that the method produces a bean to be managed by the Spring container.

• It can also be used at the class level to indicate that the class itself is a Spring bean.

• For example, @Bean annotation can be used on a method that creates and returns a DataSource bean in a configuration clas...read more

Spring and Spring Boot are popular Java frameworks used for building enterprise applications.

• Spring is a comprehensive framework that provides support for various functionalities like dependency injection, aspect-oriented programming, and transaction management.

• Spring Boot is an opinionated framework built on top of Spring, which simplifies the setup and configuration of Spring applications by providing defaults for common configurations.

• Spring Boot includes embedded servers ...read more

One disadvantage of Spring Boot is its potential for increased memory consumption.

• Spring Boot can consume more memory compared to traditional Java EE applications due to its auto-configuration and embedded server features.

• This can lead to higher resource usage and potentially slower performance.

• Developers need to be mindful of optimizing memory usage and monitoring application performance.

• Using Spring Boot for small, simple applications may result in unnecessary overhead.

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

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

• Spring Boot is an opinionated framework that simplifies the setup and development process by providing defaults for configuration.

• Spring Boot includes embedded servers like Tomcat, Jetty, or Undertow, making ...read more

Spring Boot is a framework that simplifies the development of Java applications by providing pre-configured settings and dependencies.

• Spring Boot is built on top of the Spring framework and follows the convention over configuration principle.

• It provides a standalone executable JAR file that includes an embedded server, making it easy to deploy and run applications.

• Spring Boot offers auto-configuration, which automatically configures the application based on the dependencies p...read more

Dependency Injection in Spring Boot allows for loosely coupled components by injecting dependencies at runtime.

• Dependency Injection is a design pattern where objects are passed their dependencies rather than creating them internally.

• In Spring Boot, dependencies are injected using @Autowired annotation.

• By using Dependency Injection, components can be easily swapped out and tested independently.

• Example: @Autowired private UserService userService; // Injecting UserService depend...read more

Spring is a framework for building Java applications, while Spring Boot is a tool for quickly creating stand-alone Spring-based applications.

• Spring is a comprehensive framework for building Java applications, providing support for various modules like Spring MVC, Spring Data, and Spring Security.

• Spring Boot is an opinionated tool that simplifies the setup and configuration of Spring applications, allowing developers to quickly create stand-alone, production-ready applications...read more

Spring Boot is a framework for building standalone, production-grade Spring-based applications.

• Spring Boot simplifies the process of creating and deploying Spring-based applications.

• It provides a range of features such as auto-configuration, embedded servers, and production-ready metrics.

• Spring Boot is highly customizable and can be used with a variety of other Spring projects and libraries.

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 for the creation of stand-alone, production-grade Spring-based applications.

• Spring Boot includes embedded servers like Tomcat, Jetty, or Undertow, making it easy to deploy applications.

• It offers a wide range of plugins and extensions for addition...read more

Bean scopes in Spring Boot determine the lifecycle and visibility of beans.

• Singleton scope: Default scope, only one instance per Spring container

• Prototype scope: New instance created each time bean is requested

• Request scope: Bean created once per HTTP request

• Session scope: Bean created once per HTTP session

• Application scope: Bean created once per ServletContext

Profiles in Spring Boot allow you to define different configurations for different environments.

• Profiles help in managing configurations for different environments like development, testing, production, etc.

• You can define profiles in application.properties or application.yml using 'spring.profiles.active' property.

• Profiles can be activated using command line arguments, environment variables, or servlet context parameters.

• Example: 'spring.profiles.active=dev' will activate the...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

Annotations like @Qualifier and @Transactional are used in Spring Boot for dependency injection and transaction management.

• Annotations like @Qualifier are used to specify which bean to inject when multiple beans of the same type are present.

• Annotations like @Transactional are used to mark a method as transactional, allowing for rollback in case of exceptions.

• Annotations like @Component, @Service, @Repository are used for component scanning and auto-wiring.

• Annotations like @Re...read more

Annotations in Spring Boot are used to provide metadata about the application and its components.

• Annotations are used to configure Spring Boot applications, define beans, handle requests, etc.

• Examples of annotations in Spring Boot include @SpringBootApplication, @RestController, @Autowired, @RequestMapping, etc.

Annotations in Spring Boot are used to simplify the configuration and development of Spring applications.

• Annotations are used to define the behavior of Spring components, such as controllers, services, and repositories.

• Annotations like @RestController, @Service, and @Repository are commonly used in Spring Boot applications.

• Annotations can also be used for mapping requests to controller methods, handling exceptions, and defining transaction boundaries.

• Annotations like @Autowir...read more

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 create stand-alone, production-grade Spring-based Applications.

• Spring Boot includes embedded servers like Tomcat, Jetty, or Undertow, making it easy to deploy applications.

• It offers a wide range of plugins and extensions for various...read more