Java has an enormous foothold in the enterprise with lots and lots of code running and often dating back years, if not a decade or more. That's not going to be replaced easily. The other thing is that Java users seem to be very averse to upgrading. We got a lot of backlash for releasing our newest library version for Java 8 only (so our API could offer a few niceties from that version and be less awkward to use), even though it's the only currently supported Java version by Oracle. We still have customers that use Java 1.4 ...