newbie: target generalization in jjtree, javacc

["Dean A. Hoover" <dh...@rochester.rr.com>]

Many ant targets, e.g., javac, are designed so that they will
find the source files by pattern matching or whatever. But
I notice that some of the "optional" targets I am interested
in, e.g.,  jjtree, require a specific filename (even if driven
by a property). Since I am using packages with several levels
to them (that may change in the future) I would like to have
the input to jjtree be determined heuristically. Heck, I may
very well end up with multiple .jjt files and it would be
nice to just have one task that fires off running jjtree on
each one, much like what is done with javac. Any ideas
on how to accomplish this?

Thanks.
Dean Hoover