Contributing to Spring Boot

Spring Boot is released under the Apache 2.0 license. If you would like to contribute something, or want to hack on the code this document should help you get started.

Code of Conduct

This project adheres to the Contributor Covenant code of conduct. By participating, you are expected to uphold this code. Please report unacceptable behavior to code-of-conduct@spring.io.

Using GitHub Issues

We use GitHub issues to track bugs and enhancements. If you have a general usage question please ask on Stack Overflow. The Spring Boot team and the broader community monitor the spring-boot tag.

If you are reporting a bug, please help to speed up problem diagnosis by providing as much information as possible. Ideally, that would include a small sample project that reproduces the problem.

Reporting Security Vulnerabilities

If you think you have found a security vulnerability in Spring Boot please DO NOT disclose it publicly until we’ve had a chance to fix it. Please don’t report security vulnerabilities using GitHub issues, instead head over to https://spring.io/security-policy and learn how to disclose them responsibly.

Include a Signed Off By Trailer

All commits must include a Signed-off-by trailer at the end of each commit message to indicate that the contributor agrees to the Developer Certificate of Origin. For additional details, please refer to the blog post Hello DCO, Goodbye CLA: Simplifying Contributions to Spring.

Code Conventions and Housekeeping

None of these is essential for a pull request, but they will all help. They can also be added after the original pull request but before a merge.

We use the Spring JavaFormat project to apply code formatting conventions. If you use Eclipse and you follow the "Importing into Eclipse" instructions you should get project-specific formatting automatically. You can also install the Spring JavaFormat IntelliJ Plugin or format the code from the Gradle build by running ./gradlew format. Note that if you have format violations in buildSrc, you can fix them by running ./gradlew -p buildSrc format from the project root directory.
The build includes Checkstyle rules for many of our code conventions. Run ./gradlew checkstyleMain checkstyleTest if you want to check your changes are compliant.
Make sure all new .java files have a Javadoc class comment with at least an @author tag identifying you, and preferably at least a paragraph on what the class is for.
Add the ASF license header comment to all new .java files (copy from existing files in the project).
Add yourself as an @author to the .java files that you modify substantially (more than cosmetic changes).
Add some Javadocs.
A few unit tests would help a lot as well — someone has to do it.
Verification tasks, including tests and Checkstyle, can be executed by running ./gradlew check from the project root. Note that SPRING_PROFILES_ACTIVE environment variable might affect the result of tests, so in that case, you can prevent it by running unset SPRING_PROFILES_ACTIVE before running the task.
If no-one else is using your branch, please rebase it against the current main branch (or other target branch in the project).
When writing a commit message please follow these conventions.

Working with the Code

For information on editing, building, and testing the code, see the Working with the Code page on the project wiki.