[Jprogramming] Straddling Checkerboard encoding

[Ric Sherlock]

I've made a submission for the Rosetta Code Straddling Checkerboard
task but judging by some of the other entries I'm pretty sure that it
can be significantly simplified. Any suggestions?
http://rosettacode.org/wiki/Straddling_checkerboard

(Please feel free to edit the Rosetta Code solution directly if so inclined!)