Well, our whole project stack is on java. Also, what is deprecated? I see it still being used in many companies in finance domain. Few migrated to scala, but rest are still on java. Current objective is not to be the fastest, we will reach there in due time. What we need is good design first. Then we can evaluate what and how we can do it best.Not allowed to edit so I will supplement. Its not that Java is being depreciated generally; its just that there are much better options with longer term support that most have already migrated to.
What environment?