Here is a very rough sketch of what I am trying to set up.
There are at least 2 questions asking more or less the same thing.
(1) How to intercept data being sent to a printer?
(2) Intercepting data sent to printer
(1) does have an answer, which is a link to the lpdspooler library for Java: http://lpdspooler.sourceforge.net
However my question is now how exactly do I interface with this Java library to begin intercepting print requests--ideally an example .java file would be good. I am sure it would be immediately obvious for many programmers, but I have no versing in low level tasks like printing.