Take a crack at Python and Ruby (or another language if you prefer) just to widen your experience, even if you stick to Java it will be good for you as a developer. I did the migration from Java to Python a few years back and I'm still learning and unlearning, so don't get discouraged.

One bit of advice: Try to learn a bit about proper testing as you are learning your new language, it will be easier than trying to do it after you've learned and testing will help you build confidence in your abilities in the new language.

Two good books:

"Learn Python the Hard Way" by Zed Shaw http://learnpythonthehardway.org/static/LearnPythonTheHardWa...

and/or

"Why’s (Poignant) Guide to Ruby" by _why http://mislav.uniqpath.com/poignant-guide/

Most non-rockstars forget Unix commands, it's not a big deal and you can help yourself by writing up a cheatsheet or googling for one. Practice and muscle memory helps.

I haven't had a chance to check it out but there is a PacktPub book on Python algorithms which looks interesting: "Python Algorithms: Mastering Basic Algorithms in the Python Language" by Magnus Lie Hetland

Good luck!