Did you learn how to make apps and games OR did you learn how to use J2ME? If the first, then there should not be a problem moving to a different tech. If the later, you are a bit screwed. My comment is not pointed at you, is pointed at what you said, for all I know you might be doing kernel drivers these days. I see many ex-FBers, for example, even seniors, that assume they understand tech, but it turns out they only know how to use the frameworks and systems FB has in place.