Database

Application monitoring, health checks, metrics, and observability with Spring Boot Actuator and Micrometer

Batch processing with Spring Batch including jobs, steps, chunk processing, readers, writers, and job scheduling

Core Spring Boot concepts including auto-configuration, starters, dependency injection, and application lifecycle

Microservices architecture with Spring Cloud including service discovery, API gateway, circuit breakers, and distributed configuration

Data persistence with Spring Data JPA including repositories, entity mapping, queries, and transaction management

Authentication, authorization, and security configuration with Spring Security including JWT, OAuth2, and method-level security

Testing patterns for Spring Boot applications including unit tests, integration tests, sliced tests, and test containers

Reactive programming with Spring WebFlux including Mono, Flux, non-blocking I/O, and reactive data access