I've looked into this and it's actually an issue with the PackageHtmlCheck. Rather than checking the fileset to see that it includes a corresponding package.html, it creates a File for package.html in the same directory as the java file and uses the exists() method. In order for this issue to be resolved, it would require either a fix in checkstyle or a new check implemented specifically for maven. In the end, I like to do things the maven way, but in this particular case, I'm not entirely sure that putting package.html files in a different directory even makes sense anyway. Why put just a small fraction of the javadocs in a different folder? It is a little odd to put resources like images there, but the package.html files just might be better off in src/main/java.