To be perfectly honest, this sounds like a career choice (..duh -.- )
Career choices are one of the most important decisions in one's lifetime. erm,.. I'm ranting xD
right, back to the point.
Since you already have experience as a .Net-er, I would propose for you to wait for an opening in that line of work, rather than wasting the shear amount of time you dedicated yourself to learning .Net programming, by choosing go to with Java.
Of course I've based this on the possibility that, by the time you're ready for Java, you might have found a job for .net-ting..
At the end of the of day, it's your choice, the above is just an insight.
Hope it answers more questions than it poses.
