Try different programming language for better career options

Question

I am a MTech student and have 2 years experience in .Net but most of companies coming for placements are supposed to be favouring Java like oracle, amazon. but I know these also work on .Net. So I want to ask whether it will be good idea to try programming in Java for better placements? Because my concern is regarding the disadvantage due to being start in .Net and their work area being of Java based technologies.