I have finished now my work on integrating last PMD version 5.0.5 into JDeveloper.
This is available now for JDeveloper 18.104.22.168 upwards, 11.1.2.x. and 12.1.2. There is no new functionality, as the most work intensive part was the rewriting for PMD 5. There has changed a lot of api functionality.
Please give it a try, you can download it via the standard update center "Open Source and Partners Extensions" in JDveloper itself
or directly from the PMD SourceForge.net Project Page.