A decade or so ago I found myself in need of a Java command line option parser. Unsatisfied with free versions I was able to find on the net, I volunteered to port the GNU getopt family of functions from C to Java. The current release is 1.0.13 (released 2006/08/29).
The GNU Java getopt classes support short and long argument parsing in a manner 100% compatible with the version of GNU getopt in glibc 2.0.6 with a mostly compatible programmer's interface as well. Note that this is a port, not a new implementation. I am currently unaware of any bugs in this software, but there certainly could be some lying about. I would appreciate bug reports as well as hearing about positive experiences.
Just Say No to Frames, Ads, Flash, and Animated GIF's