Spring Transactions In-Depth

Explore dependency injection and inversion of control in spring, wire services with constructor injection, manage beans via the application context, and validate correct bean instances in tests.

Build your first Spring Boot project from start.spring.io with Maven and Java, adding Spring Web and an embedded Tomcat. Run the standalone jar and verify the server on localhost:8080.

Build a Spring Boot MVC REST controller to manage users at /users, implementing get, post, put, and delete operations with JSON responses and user domain, payload DTO, and Postman testing.

Introduce a user service interface and impl, register as a spring bean, and delegate get all users, get user, create, update, and delete to the service via IoC.

Refactor the service layer into a repository layer, implement a user repository with findAll, findById, save, and deleteById, and move ID generation to the repository.

Configure an H2 in-memory database with file persistence for Spring Data JPA, enabling data to survive restarts and access via the H2 console.

Install Docker and MySQL, run MySQL in a container for integration tests and an Angular app, and use docker run and docker exec with port mappings.

Explore how Spring transaction provides a powerful, high level abstraction for managing database transactions, ensuring data consistency, and simplifying database interaction in Spring Boot applications.

Apply transactional annotation to automatically manage transactions in the service layer, ensuring a single cohesive transaction for create category operations and avoiding controller-level misuse.

Implement transactional updates for categories in a Spring Boot app, ensuring consistency and integrity, covering update category, payload usage, transactional annotation, and Hibernate dirty checking.

Develop the checkout flow by implementing customer, order, and order item entities with repositories and services, then compare checked versus unchecked exceptions and their transaction effects.

Explore transaction boundaries and how threading and async execution affect whether methods run in the same or a new transaction, and why propagation and cross-thread execution impact data consistency.

Explore edge cases where transactional event listeners don't trigger, adjust order so balance deduction precedes 5% credit, and use propagation phase of before commit or the saga pattern for consistency.

Learn how fallback execution in transactional event listeners lets you react to events outside an active transaction, ensuring data consistency across transactional and non-transactional scenarios.

Explore MySQL isolation levels with docker-based hands-on demos, from read uncommitted to serializable, and observe how commits, rollbacks, and spring transactional annotations affect consistency.