Top 16 Spring Boot Best Practices for Building Robust Microservices

Spring Boot is the most popular Java framework for developing microservices. In this article, the author shares best practices used since 2016, based on personal experience and insights from Spring Boot experts.

The focus is on Spring Boot‑specific practices (most of which also apply to plain Spring projects). The following best practices are listed in no particular order.

Feel free to comment at the end and share your own Spring Boot best practices.

1. Use a custom BOM to manage third‑party dependencies

This practice stems from real project experience. Spring Boot integrates many open‑source libraries, but some required dependencies may be missing, especially in large projects with many modules.

Inspired by Spring IO Platform, you can create your own platform‑bom and import it in all business modules, simplifying version upgrades.

<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>io.spring.platform</groupId>
      <artifactId>platform-bom</artifactId>
      <version>Cairo-SR3</version>
      <type>pom</type>
      <scope>import</scope>
    </dependency>
  </dependencies>
</dependencyManagement>

2. Leverage auto‑configuration

Auto‑configuration is a core Spring Boot feature that simplifies code by activating configuration when specific JARs are on the classpath.

The simplest way is to depend on Spring Boot Starters. For Redis integration, include:

<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

For MongoDB integration, include:

<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency>

Starters provide tested, verified dependencies and help avoid "Jar hell".

https://dzone.com/articles/what-is-jar-hell

You can exclude specific auto‑configuration classes when absolutely necessary:

@EnableAutoConfiguration(exclude = {ClassNotToAutoconfigure.class})

Official auto‑configuration docs: Spring Boot Auto‑Configuration

3. Start new projects with Spring Initializr

This practice comes from Josh Long (Spring Advocate).

Spring Initializr offers a simple way to generate a new Spring Boot project with the required dependencies.

https://start.spring.io/

Using Initializr ensures you get tested, verified dependencies that work with Spring's auto‑configuration.

4. Create custom auto‑configuration for common organizational concerns

For teams heavily reliant on Spring Boot, building shared auto‑configuration can solve recurring problems and be packaged as an open‑source library.

5. Design a clean code directory structure

Avoid the default package, place the entry point (Application.java) at the top level, and organize controllers and services by functional modules.

6. Keep @Controller simple and focused

Controllers should be stateless, delegate business logic, handle only HTTP concerns, and be designed around use cases.

https://en.wikipedia.org/wiki/GRASP#Controller

7. Build @Service around business capabilities

Name services by domain concepts (e.g., AccountService, UserService) rather than generic terms like DatabaseService.

8. Isolate the database from core business logic

Follow "Clean Architecture" principles: treat the database as a detail and keep services unaware of the specific persistence implementation.

Robert C. Martin emphasizes keeping the database as a detail to avoid tight coupling.

9. Protect business logic from Spring Boot code intrusions

Avoid mixing Spring annotations directly into core business classes to keep the logic reusable and testable.

10. Prefer constructor injection

Constructor injection (optionally without @Autowired) makes beans easy to instantiate outside of Spring.

@Autowired // optional on constructor
public MyService(Dependency dep) { ... }

11. Understand the concurrency model

Controllers and services are singletons by default, which can introduce concurrency issues if not handled properly.

https://www.e4developer.com/2018/03/30/introduction-to-concurrency-in-spring-boot/

12. Externalize configuration management

Use a configuration server (e.g., Spring Cloud Config) or store configurations in environment variables for multiple services.

13. Provide global exception handling

Use HandlerExceptionResolver or @ExceptionHandler on controllers for consistent error handling.

https://www.baeldung.com/exception-handling-for-rest-with-spring

14. Use a logging framework

Prefer a logger over System.out.println(). Example:

Logger logger = LoggerFactory.getLogger(MyClass.class);

15. Test your code

Write tests to avoid legacy code and consider Spring Cloud Contract for consumer‑driven contracts.

16. Use test slices for focused testing

Test slices allow loading only parts of the application, speeding up tests and reducing unnecessary dependencies.

https://spring.io/blog/2016/08/30/custom-test-slice-with-spring-boot-1-4

Summary

Thanks to Spring Boot, building Spring‑based microservices has become easier than ever. By applying these best practices, you can develop faster, more robust, and maintainable applications.