Java API Development: From Design to Production

The book "Java API Development" is a comprehensive practical guide for Java developers who want to master creating modern, scalable, and secure APIs. The author systematically takes the reader from the basics of interface design to deploying a finished service in production.

What the book covers:

• Principles of RESTful architecture and their implementation in Java
• Designing endpoints, working with HTTP methods and status codes
• Deep dive into Spring Boot: controllers, services, repositories
• Error handling, data validation, and logging
• Authentication and authorization: JWT, OAuth2, Spring Security
• API documentation with Swagger/OpenAPI
• Testing: unit, integration, and load testing (JUnit, Mockito, Postman)
• Working with databases via JPA and Hibernate
• Asynchronous APIs and reactive programming (WebFlux)
• Microservice architecture and inter-service communication
• GraphQL as an alternative to REST: queries, mutations, subscriptions
• CI/CD, containerization with Docker, and orchestration

Who this book is for:

• Junior and Middle Java developers looking to deepen their backend development skills
• Developers transitioning to Java from other languages
• IT students studying industrial programming
• Tech leads and architects seeking a systematic approach to API creation

What the reader will learn:

• How to properly design an API from scratch, avoiding common mistakes
• How to use Spring Boot for rapid REST service development
• How to protect an API from unauthorized access and attacks
• How to write tests that actually verify business logic
• How to document an API so it is easy to maintain
• How to deploy an application to the cloud and set up monitoring

The book contains many practical examples, ready-to-use code, and exercises for independent work. All examples are based on current versions of Java 17+ and Spring Boot 3.x. The book is suitable both for self-study and for use as a reference in daily work.