Spring Framework
The container itself: IoC, bean lifecycle, AOP proxies, transactions and the web layer — where the magic stops being magic.
1. IoC Container & Dependency Injection
What the container actually does at startup, injection styles, circular dependencies and wiring control.
2. Bean Lifecycle & Scopes
From instantiation to destruction, the post-processor pipeline, and scope interactions that bite in production.
3. Aspect-Oriented Programming
Proxies, pointcuts and advice — the mechanism behind @Transactional, @Cacheable, @Async and their pitfalls.
4. Transaction Management
@Transactional under the hood, propagation, isolation, rollback rules — and life beyond single-database ACID.
5. Spring MVC & the Web Layer
DispatcherServlet internals, error handling contracts, filters vs interceptors, validation and the WebFlux question.
6. Data Access & ORM Integration
Spring's data-access abstractions, the JPA persistence context, N+1 hunting, OSIV and locking strategies.