Instead of worrying about that; why not make yourself future-proof? Like I just said, no one can predict the future in the technology domain; because things change here every single minute. As a software engineer / developer – you should *not* stick to any specific language; yet master one that you are currently working on. Let me make it very clear : You need to be master of at least one and jack of several! Any programming language is just a set of tools that help you implement logic. If you hone your logic skills; you should be able to get comfortable with any programming language, tool or framework within short time. I’ve seen that happen with few of my ex-colleagues.
Start with any – and learn it with all the interest and try to be excellent. If you pick up Java; don’t hate .Net and vice-versa. If your current job demands C# and ASP; learn it. If you are just starting out with a big IT company that has not told you which profile they will assign to you; it just doesn’t matter.