Firstly - thanks for thinking about contributing!
The build has three tools that are used to ensure code quality:
- Checkstyle - this is used to ensure that the code adheres to a consistent style.
- PMD - this is used to find common programming flaws.
- SpotBugs - this is used to find common bugs in Java code.
Before submitting a pull request, please ensure that the code passes all of these checks. You can run them locally by executing mvn clean verify.