Spring Framework Java Interview Questions

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Preparing for a Java developer interview in 2026?
Then mastering the Spring Framework is non-negotiable.

From startups to Big Tech, Spring continues to dominate enterprise Java development—and interviewers no longer ask basic definitions. Instead, they test real-world behavior, architectural thinking, and production-level knowledge.

Spring Framework Java Interview Questions

This guide covers the Top 30 Spring Framework interview questions that are frequently asked in real interviews, explained clearly for freshers, experienced developers, and senior engineers.

Whether you’re targeting Spring Boot, REST APIs, Microservices, or Spring Security, this article will sharpen your interview readiness.

Why Spring Framework Matters in Java Interviews (2025)

Spring Framework simplifies enterprise Java development by providing powerful abstractions for:

  • Dependency management
  • Transaction handling
  • Web and REST APIs
  • Security and microservices

Its core principles—Dependency Injection (DI) and Aspect-Oriented Programming (AOP)—help developers write clean, testable, and scalable code. Interviewers love Spring because it reveals how well you understand software design, not just syntax.

Core Spring Framework Interview Questions

1. What is Spring Framework and why is it used?

Spring is an open-source Java framework that provides infrastructure support for building enterprise applications. It reduces boilerplate code and promotes loose coupling through Dependency Injection.

Key features:

  • Dependency Injection (IoC)
  • Aspect-Oriented Programming (AOP)
  • Declarative Transaction Management
  • Spring MVC for web applications
  • JDBC abstraction and ORM integration

2. What is Dependency Injection in Spring?

Dependency Injection is a design pattern where objects receive their dependencies from the Spring container instead of creating them manually.

Types of dependency injection:

  • Constructor Injection (recommended)
  • Setter Injection
  • Field Injection (@Autowired)

Constructor injection is preferred because it improves immutability and testability.

3. Difference between BeanFactory and ApplicationContext?

  • BeanFactory: Basic container with lazy initialization
  • ApplicationContext: Advanced container with enterprise features

ApplicationContext supports:

  • Event publishing
  • Internationalization (i18n)
  • AOP integration
  • Annotation-based configuration

👉 In real-world applications, ApplicationContext is always preferred.

4. What are Spring Bean scopes?

Spring supports multiple bean scopes depending on application type.

Common scopes:

  • Singleton (default)
  • Prototype
  • Request
  • Session
  • Application
  • WebSocket

Understanding scopes is crucial for thread safety and performance.

5. Explain the Spring Bean lifecycle

Spring bean lifecycle phases:

  1. Bean instantiation
  2. Dependency injection
  3. Initialization (@PostConstruct)
  4. Bean ready for use
  5. Destruction (@PreDestroy)

Spring allows hooks at each stage for custom logic.

Spring Boot Interview Questions (Most Asked)

6. What is Spring Boot and why is it popular?

Spring Boot is built on top of Spring Framework and removes configuration complexity by providing:

  • Auto-configuration
  • Embedded servers
  • Starter dependencies
  • Production-ready features

Spring Boot follows convention over configuration, making development faster and cleaner.

7. How does @Autowired work?

@Autowired enables automatic dependency injection by type.

If multiple beans of the same type exist:

  • Use @Qualifier
  • Or mark one bean as @Primary

Best practice: use constructor injection instead of field injection.

8. What is Spring AOP and where is it used?

Spring AOP separates cross-cutting concerns from business logic.

Common use cases:

  • Logging
  • Security
  • Transaction management
  • Performance monitoring

AOP improves code maintainability without modifying existing logic.

9. What are the types of Advice in Spring AOP?

Spring provides five advice types:

  • Before
  • After
  • After Returning
  • After Throwing
  • Around (most powerful)

Around advice can control method execution entirely.

10. Explain Spring MVC architecture

Spring MVC follows the Model-View-Controller pattern.

Core components:

  • DispatcherServlet (front controller)
  • HandlerMapping
  • Controllers
  • ViewResolver
  • Views

DispatcherServlet coordinates the complete request lifecycle.

Advanced Spring Interview Questions

11. How does Spring transaction management work?

Spring supports:

  • Programmatic transactions
  • Declarative transactions using @Transactional

Declarative transactions are preferred because they keep business logic clean.

Spring supports:

  • Propagation behaviors
  • Isolation levels
  • Rollback rules

12. Transaction propagation types in Spring

Spring defines seven propagation behaviors:

  • REQUIRED (default)
  • REQUIRES_NEW
  • SUPPORTS
  • NOT_SUPPORTED
  • MANDATORY
  • NEVER
  • NESTED

These control how transactions behave across method calls.

13. What is Spring Data JPA?

Spring Data JPA simplifies database access by eliminating boilerplate DAO code.

Key benefits:

  • Repository interfaces
  • Query method naming
  • Pagination & sorting
  • Custom queries using @Query

It dramatically increases development speed.

14. What does @SpringBootApplication do?

It combines:

  • @Configuration
  • @EnableAutoConfiguration
  • @ComponentScan

This single annotation bootstraps the entire Spring Boot application.

15. Difference between @Component, @Service, @Repository, @Controller

They are stereotype annotations for different layers:

  • @Component: Generic
  • @Service: Business logic
  • @Repository: Data access + exception translation
  • @Controller: Web layer

Using the correct stereotype improves readability and tooling support.

Spring Security Interview Questions

16. What is Spring Security?

Spring Security handles authentication and authorization.

Features include:

  • Role-based access control
  • CSRF protection
  • OAuth2, JWT, LDAP integration
  • Method-level security

17. Explain JWT authentication in Spring Security

JWT authentication is stateless:

  1. User logs in
  2. Server generates JWT
  3. Client sends token with each request
  4. Server validates token

JWTs scale well for microservices architectures.

18. What is CSRF and how does Spring handle it?

CSRF attacks force authenticated users to perform unwanted actions.

Spring Security prevents this using CSRF tokens.
For stateless REST APIs using JWT, CSRF protection is usually disabled.

Spring Boot Actuator & Configuration

19. What are Spring Boot starters?

Starters are dependency bundles that include everything needed for a feature.

Example:

  • spring-boot-starter-web
  • spring-boot-starter-security

They ensure dependency compatibility.

20. What is Spring Boot auto-configuration?

Auto-configuration configures beans based on:

  • Classpath dependencies
  • Existing beans
  • Application properties

You can view auto-configuration decisions in debug logs.

21. Purpose of application.properties or application.yml?

These files externalize configuration:

  • Database settings
  • Ports
  • Logging
  • Feature toggles

YAML is preferred for complex configurations.

22. Custom health checks in Spring Boot

Implement HealthIndicator to create custom health checks.

Spring Boot aggregates all indicators under /actuator/health.

Microservices & REST Interview Questions

23. What is Spring Cloud?

Spring Cloud simplifies microservices development by handling:

  • Service discovery
  • Configuration management
  • Circuit breakers
  • API gateways

24. How does Eureka service discovery work?

Services register with Eureka Server.
Clients discover services dynamically, enabling:

  • Scalability
  • Fault tolerance
  • Load balancing

25. What is Circuit Breaker pattern?

Circuit breakers prevent cascading failures.

Spring uses Resilience4j to implement circuit breakers with annotations like @CircuitBreaker.

26. How to create REST APIs in Spring?

Use:

  • @RestController
  • @GetMapping, @PostMapping
  • @RequestBody, @PathVariable

Spring automatically converts objects to JSON using Jackson.

27. Global exception handling in Spring REST APIs

Use @ControllerAdvice with @ExceptionHandler.

This ensures:

  • Consistent error responses
  • Clean controller code

28. What is content negotiation?

Content negotiation allows APIs to serve:

  • JSON
  • XML
  • Custom formats

Based on request headers or parameters.

Testing Interview Questions

29. How to test Spring applications?

Spring provides:

  • @SpringBootTest
  • @WebMvcTest
  • @DataJpaTest
  • @MockBean

JUnit 5 + Mockito are industry standards.

30. Difference between @Mock and @MockBean?

  • @Mock: Mockito-only, no Spring context
  • @MockBean: Replaces beans inside Spring context

Use @MockBean for integration tests.

Final Interview Preparation Tips

  • Understand why, not just what
  • Be ready to explain real project use cases
  • Know modern Spring features (WebFlux, native builds)
  • Practice writing REST APIs and annotations

Conclusion

Spring Framework interviews test your design thinking, architecture skills, and real-world experience.

If you can confidently explain most of these questions with examples, you’re well-prepared for Spring interviews in 2026.

Keep practicing, stay updated, and approach interviews with confidence.

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