Spring Boot 4 for Absolute Beginners: Build real Java web applications from your very first line of code

You need to know basic Java. That is genuinely all. Everything else - HTTP, Maven, SQL, Docker, testing - is explained the first time it appears, in plain words, with no assumed background.

You will build one small application and grow it across fifteen chapters: a web API, then a real database, then caching, security, messaging, monitoring and deployment. By the end you will have written the kind of service that runs in production.

What you will learn

• Your first project, and what the framework is really doing behind the annotations


• REST APIs with validation, error handling and versioning


• SQL and NoSQL data access, with your queries written for you


• Testing at every level, against real databases in containers


• Security, messaging, metrics, tracing and native images


• API gateways, circuit breakers, and building your own Spring Boot starter

Every listing was compiled and run against Spring Boot 4.1.1 on Java 25 before it was printed - with real PostgreSQL, MongoDB, Redis, RabbitMQ and Kafka. The log output, JSON responses and error messages in this book came from actual program runs, not from imagination.

Version 4 renamed a great many things. If you have read older tutorials, some of what you remember is now wrong. This book teaches the new way from the first page.