In your own documentation at
you say "Different programming languages have different comment syntax rules".
However I can not find a way to tell checks such as Header or RegexpHeader to work only on .java Files.
My header is multiline / ... / comment that can not be used in properties-files.
However checkstyle complains about the missing header in properties-files.
Either documentation is missing importation information or there is an important feature missing in checkstyle to
be able to allow different Filters for different file-formats.