OK.. it appears that Java is used in the indexing of the Files Module. (I wonder if it can read and index the contents of large pdf files, book size... Yep, that would take up some serious server resources.)

Most of all... is there a fall-back for those of us on a java-less hosting arangement which would enable us to use the File Module without the indexing??? One without users recieving some kind of error message?  

Files could still be searched by their titles, categories, and hash tags (keywords), right?

Thank you, readers, for every consideration.