I theoretically understand the point why there is no abstract static in Java, as explained for instance in Why can't static methods be abstract in
I don't know how a java guru would solve it, but I'd probably create a resource bundle with all the descriptions in a properties file like this:
com.bigcompany.smallapp.files.DataFile=Data file
com.bigcompany.smallapp.files.ConfigFile=Config file
Handling the bundle can conveniently be placed in the superclass or elsewhere.
Another option is to use reflection to access the static fields in each subclass, but then you need to make sure that all the subclasses have a static field with the same name.
There could be other options too, even refactoring the code so that the subtypes aren't represented by a separate class each, but in general there's no watertight solution.