Further Resources
Official
- Spring Boot reference — the manual, worth skimming end to end once
- Spring Boot 4.0 release notes — every change, with migration notes
- Spring Framework reference — the container, MVC, transactions
- Guides — short, task-shaped tutorials
- start.spring.io — project generator
- spring.io/blog — release announcements and deep dives
What is new in Spring Boot 4
| Topic | Where |
|---|---|
| Modularization, JSpecify null safety, Java 25 | Spring Boot 4.0 announcement |
| API versioning | Framework 7 GA |
| HTTP service clients | Spring Boot reference: REST clients |
@Retryable, @ConcurrencyLimit | Framework reference: resilience |
RestTestClient, @MockitoBean | Spring Boot reference: testing |
Ecosystem
- Spring Data JPA — repositories, derived queries
- Spring Security — dense, but the only reliable source
- Micrometer — metrics and tracing
- Testcontainers — real databases in tests
- Flyway — schema migrations
- JSpecify — the null-safety annotations
Tools
- Eclipse Temurin — JDK builds
- SDKMAN! — manage several JDKs
- MVN Repository — find library coordinates
- HTTPie / curl — talk to your endpoints
- Spring Boot Migrator / OpenRewrite — automated upgrades
Practice
- Rebuild the course project without looking: entity, repository, service, controller, tests
- Put a real API behind an
@HttpExchangeinterface - Take an existing Spring Boot 3 app and upgrade it to Spring Boot 4
- Deploy something small — a container plus a health probe teaches more than a chapter
Books
- Spring Start Here (Laurentiu Spilca) — gentle, container-first
- Spring in Action (Craig Walls) — broad tour of the ecosystem
- Spring Boot: Up and Running (Mark Heckler) — practical, production-minded
- Effective Java (Joshua Bloch) — not Spring, but it makes your Spring code better
Community
- Stack Overflow — check the date on every answer
- GitHub issues — the maintainers answer here
- Devoxx, Spring I/O and SpringOne talks are on YouTube
Tip
Check the version of anything you read. A lot of “how to do it in Spring” describes XML
configuration or Spring Boot 1 — if a snippet has applicationContext.xml in it, keep scrolling.
About this course
All code samples are public domain (CC0). Written against Spring Boot 4.0 on JDK 25.