GSoC project page


About Checkstyle


Checkstyle is a tool for checking Java source code for adherence to a Code Standard or set of validation rules (best practices). Checkstyle is generally run either using it's main method or by supplying the checkstyle jar the java command. Checkstyle also has a GUI to work with. To use checstyle all you need is a config file which specifies which checks you want to run and their properties and the java files you want to run the checks on. Checkstyle also gives you to write your custom checks though it of course takes some acquaintaince with the checkstyle source code to do that.

Basically checkstyle creates parse trees after reading file contents. The parse trees are based on the grammars that have been constructed, separately, for java and javadoc content by checkstyle developers and are created using the ANTLR tool. All the needed checks are then run on this parse tree.

The latest release version can be found at SourceForge downloads or at Maven repository.

Each-commit builds of maven artifacts can be found at Maven Snapshot repository.

Documentation is available in HTML format at

Mailing lists

General discussions:!forum/checkstyle

Release notifications:!forum/checkstyle-announce