[kotakota]

As many other people have said it depends on what you want to do. You should choose a language for a project based on the project.

With that being said there are a lot of jobs available for programmers who know java, c++, and .net. If you want to do desktop developement work i would suggest being compitent in those languages but if you want to do web dev work you should probably skip those languages for the time being and focus on languages that are better suited for that domain.