Spring Boot Study Guide 2026
Everything you need to pass the Spring Boot exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 Spring Boot Exam Format at a Glance
📚 Spring Boot Topics to Study (21)
✍️ Sample Spring Boot Questions & Answers
1. How do you implement cross-field validation (e.g., confirming a password matches) using Bean Validation?
Cross-field validation can be done with @ScriptAssert (quick, uses scripting engine) or a custom class-level constraint with a ConstraintValidator that receives the whole object; both are standard approaches.
2. What property in `application.properties` switches the Spring Boot web application type to reactive?
Setting `spring.main.web-application-type=reactive` forces Spring Boot to start a reactive web environment using WebFlux instead of the servlet stack.
3. What does the `@Cacheable` annotation do when applied to a Spring service method?
`@Cacheable` intercepts the method call, checks the named cache for an existing entry, and only invokes the method on a cache miss.
4. In a Spring Boot application, which annotation is considered the most generic stereotype for marking a class as a Spring-managed component?
@Component is the generic stereotype annotation for any Spring-managed component. @Service, @Repository, and @Controller are specializations of @Component for more specific use cases in the service, persistence, and presentation layers, respectively.
5. What is the purpose of the `@CacheEvict` annotation?
`@CacheEvict` triggers removal of specific entries (or all entries with `allEntries=true`) from the named cache when the annotated method is called.
6. In Spring WebFlux, what is the role of the `ServerRequest` object in a `HandlerFunction`?
`ServerRequest` provides access to the HTTP method, URI, headers, and body of an incoming request inside a `HandlerFunction`.