Spring Boot Best Practices for Developers

Spring Boot is a widely used and very popular enterprise-level high-performance framework. Here are some best practices and a few tips you can use to improve your Spring Boot application and make it more efficient. This article will be a little longer, and it will take some time to read the article completely.

Proper packaging style

• Proper packaging will help to understand the code and the flow of the application easily.
• You can structure your application with meaningful packaging.
• You can include all your controllers in a separate package, services in a separate package, util classes into a separate package…etc. This style is very convenient for small-sized microservices.
• If you are working on a huge code base, a feature-based approach can be used. You can decide on your requirement.

Based on type

Based on the feature

Use design patterns

• No complaints. Design patterns are already best practices.
• But you must identify the place where you can use them.
• Please check this article to understand “how to use the Builder design pattern” in our Spring Boot applications.

Use Spring Boot starters

• This is a cool feature of Spring Boot.
• We can very easily use starter dependencies without adding single dependencies one by one. These starter dependencies are already bundled with the required dependencies.
• For example, if we add spring-boot-starter-web dependency, by default it is bundled with jackson, spring-core, spring-mvc, and spring-boot-starter-tomcat dependencies.
• So we don’t need to care about adding dependencies separately.
• And also it helps us to avoid version mismatches.

Use proper versions of the dependencies

• It is always recommended to use the latest stable GA versions.
• Sometimes it may vary with the Java version, server versions, the type of the application…etc.
• Do not use different versions of the same package, and always use <properties> to specify the version if there are multiple dependencies.

Use Lombok

• As a Java developer, you have probably heard of the Lombok project.
• Lombok is a Java library that can be used to reduce your code and allow you to write clean code using its annotations.
• For example, you may use plenty of lines for getters and setters in some classes like entities, request/response objects, dtos…etc.
• But if you use Lombok, it is just one line, you can use @Data, @Getter, or @Setter as per your requirement.
• You can use Lombok logger annotations as well. @Slf4j is recommended.
• Check this file for your reference.

Use constructor injection with Lombok

• When we talk about dependency injection, there are two types.
• One is “constructor injection” and the other is “setter injection”. Apart from that, you can also use “field injection” using the very popular @Autowired annotation.
• But we highly recommend using Constructor injection over other types. Because it allows the application to initialize all required dependencies at the initialization time.
• This is very useful for unit testing.
• The important thing is that we can use the @RequiredArgsConstructor annotation by Lombok to use constructor injection.
• Check this sample controller for your reference.

Please refer to this to see more tips and read the complete article.