dependency checking with ant

[Danny Zapata <dz...@bea.com>]

How would you do any non *.java dependency checking with ant?  

For example, I have to run an idl compiler to generate *.java files.  I
would be very helpful if ant could somehow check to see if the idl files
changed before running the compiler.  Currently I have a few projects that
depend on the idl project, so during a build the idl project will get called
several times and it will generate the .java source as well.

This will also be important when I try and port our C++ projects over to
ant.  

Thanks,
Danny