The following Real-time interview questions of Spring Boot were asked in a Tier 1 services company, making them highly valuable for job seekers seeking to excel in their interviews and thoroughly prepare for the process.
What is Springboot
– Spring Boot is a framework for building Java applications, specifically focused on creating stand-alone, production-grade Spring-based applications with minimal configuration. It is part of the larger Spring ecosystem and provides a streamlined approach to developing Java applications by reducing boilerplate code and providing opinionated defaults.
Explain the concept of auto-configuration in Spring Boot
– Auto-configuration automatically configures the Spring application based on the dependencies in the classpath. It eliminates the need for explicit configuration and reduces boilerplate code.
How can you override the default configurations in Spring Boot?
– Default configurations in Spring Boot can be overridden by providing your own configuration files, using the @Configuration annotation, or by modifying properties in the application.properties or application.yml file.
What is the purpose of the @SpringBootApplication annotation?
– The @SpringBootApplication annotation is a convenience annotation that combines the @Configuration, @EnableAutoConfiguration, and @ComponentScan annotations. It is commonly used to bootstrap a Spring Boot application.
How can you access external properties in a Spring Boot application?
– External properties can be accessed in a Spring Boot application by using the @Value annotation or by injecting the Environment object. Additionally, properties can be defined in the application.properties or application.yml file.
How can you handle exceptions in Spring Boot?
– Exceptions in Spring Boot can be handled using the @ExceptionHandler annotation to define exception-specific handlers, or by using the @ControllerAdvice annotation to define global exception handlers for the entire application.
What is Spring Boot Actuator? How does it help in monitoring and managing the application?
– Spring Boot Actuator is a sub-project of Spring Boot that provides production-ready features to monitor and manage the application. It offers endpoints to access metrics, health checks, log files, and more. With Actuator, you can easily gather insights into the running application and perform management tasks.
What is the purpose of the @RestController annotation in Spring Boot?
– The @RestController annotation is a specialized version of the @Controller annotation. It is used to annotate a class that combines the functionality of @Controller and @ResponseBody. It is commonly used to build RESTful web services in Spring Boot.
How can you implement authentication and authorization in a Spring Boot application?
– Authentication and authorization can be implemented in a Spring Boot application by integrating with security frameworks like Spring Security. You can define authentication providers, configure access rules, and apply security annotations to secure your endpoints.
What is the role of Spring Boot Starter dependencies?
– Spring Boot Starter dependencies are a set of curated dependencies that provide a predefined set of dependencies for specific functionalities. They simplify dependency management by including compatible versions of the required libraries, making it easier to configure and bootstrap your application.
Explain the difference between @Component, @Service, and @Repository annotations in Spring Boot.
– In Spring Boot, the @Component annotation is a generic stereotype annotation used to annotate any Spring-managed component. The @Service annotation is a specialization of @Component and is used to annotate classes that perform business logic. The @Repository annotation is also a specialization of @Component and is used to annotate classes that interact with the database.
How can you enable cross-origin resource sharing (CORS) in a Spring Boot application?
– To enable CORS in a Spring Boot application, you can use the @CrossOrigin annotation on a specific controller or globally configure CORS by implementing a WebMvcConfigurer and overriding the addCorsMappings() method.
Explain the purpose of the application.properties (or application.yml) file in a Spring Boot application.
– The application.properties or application.yml file is used to configure various properties for a Spring Boot application. It allows you to customize settings related to the application’s environment, database connections, logging, and more.
How can you handle internationalization (i18n) in a Spring Boot application?
– In Spring Boot, internationalization can be achieved by using the MessageSource interface and defining message properties files for different languages. By configuring the appropriate locale resolver and using MessageSource in your application, you can support multiple languages and dynamically retrieve localized messages.