Spring Boot Best Practices: 16 Essential Tips for Building Robust Microservices

Spring Boot is the most popular Java framework for developing microservices. Since 2016, the author has collected a set of best practices based on personal experience and insights from other Spring Boot experts.

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

Maintain a platform‑BOM (similar to Spring IO Platform) to centralize versions of external libraries, making upgrades easier.

<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 simplifies code by activating configuration when specific JARs are on the classpath. Use Spring Boot Starters for common integrations, e.g., Redis and MongoDB.

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

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

Exclude specific auto‑configurations only when absolutely necessary:

@EnableAutoConfiguration(exclude = {ClassNotToAutoconfigure.class})

3. Start new projects with Spring Initializr

Use https://start.spring.io/ to generate a clean, tested project with the required dependencies.

4. Create custom auto‑configuration for common organizational concerns

When a team repeatedly faces the same configuration challenges, package them as reusable auto‑configuration libraries.

5. Design a clear code directory structure

Avoid the default package, keep the main application class at the top level, and group controllers and services by feature or module.

6. Keep @Controller classes simple and focused

Controllers should be stateless, delegate business logic to services, and handle only HTTP concerns. See GRASP Controller pattern for details.

7. Build @Service beans around business capabilities

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

8. Isolate the database layer from core business logic

Follow "Clean Architecture" principles: treat the database as a detail and keep persistence concerns separate from services.

9. Protect business logic from Spring Boot intrusions

Avoid sprinkling Spring annotations throughout core code so that the domain can be reused outside the framework.

10. Prefer constructor injection

Constructor injection makes beans easier to test and removes the need for @Autowired on fields.

11. Understand the concurrency model

Be aware that controllers and services are singletons; manage thread pools and avoid mutable shared state.

12. Externalize configuration management

Use Spring Cloud Config or environment variables to centralize configuration across multiple services.

13. Provide global exception handling

Implement a HandlerExceptionResolver or use @ExceptionHandler on controllers for consistent error responses.

14. Use a proper logging framework

Replace System.out.println with a logger:

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

15. Test your code thoroughly

Write unit and integration tests; consider contract testing with Spring Cloud Contract for consumer‑driven contracts.

16. Use test slices to focus tests

Leverage Spring Boot test slices to load only the parts of the application needed for a specific test scenario.

By following these practices, developers can create Spring Boot‑based microservices that are faster to implement, easier to maintain, and more robust in production.