PMD is a static source code analyzer. It finds common programming flaws like unused variables, empty catch blocks, unnecessary object creation, and so forth. It’s mainly concerned with Java and Apex, but supports six other languages.
PMD features many built-in checks (in PMD lingo, rules), which are documented for each language in our Rule references. We also support an extensive API to write your own rules, which you can do either in Java or as a self-contained XPath query.
PMD is most useful when integrated into your build process. It can then be used as a quality gate, to enforce a coding standard for your codebase. Among other things, PMD can be run:
CPD, the copy-paste detector, is also distributed with PMD. You can also use it in a variety of ways, which are documented here.
The latest release of PMD can be downloaded from our Github releases page.
The rest of this page exposes the contents of the documentation site thematically, which you can further scope down using the blue filter buttons. To navigate the site, you may also use the search bar in the top right, or the sidebar on the left.
These pages document the process of writing and testing custom rules and metrics for PMD.