See http://playground.arduino.cc/Interfacing/Processing for more info.

Note: The build process (as defined in build.xml) copies 2 jar files from the Processing application and assumes Processing is installed on OS X in the Applications directory so the following build instructions will currently only work for OS X.

To build:

1. Ensure you have Apache Ant installed.
2. From the root directory, run: ant This will generate a few directories, but ultimately all you need is the updated processing-arduino.zip file.
3. Run: ant clean to remove the generated files and directories