It's not a "bad" decision if you focus on Android development or you are working for a big company with Java infrastructure (that pay's my bills :). How ever, a

It's not a "bad" decision if you focus on Android development or you are working for a big company with Java infrastructure (that pay's my bills :). How ever, as they say: "don't keep all your eggs in just one basket". Learn other languages and frameworks like PHP/Yii, Python/Django or Ruby/Ruby On Rails. And code for different platforms (iOS, Windows Phone) if you have the time ;)