I want to use processing-java with the --build flag for on-the-fly syntax checking ptrv/processing2-emacs#8.

The problem I'm facing on OSX is that every time processing-java is run it steals focus from the editor, even though no window is created. This makes editing the code as syntax checking is running a frustrating experience. I can reproduce this by running processing-java from the terminal as well.

I found out a fix, which is to add -Djava.awt.headless=true to the java run options in /usr/local/bin/processing-java. I didn't notice any issues when running my sketches, but does anyone more knowledgeable in Java settings know what that headless-option could break?