Why use age instead of a knowledge check instead?

It’s not a back door, it’s just a rear entryway

It’s been interesting seeing the changes as they happened over time working with java pretty often for a good chunk of that time. The jvm and jit performance improvements, syntax changes and additional jep features added vs what was left out, tools for running and managing jvms, Sun & Oracle shooting themselves in the foot repeatedly, new jvm languages with scala, groovy, clojure, etc and their impact on java. I prefer other languages and tool chains for some cases, but java has been pretty good for building reliable, upgradable, extendable systems that get the job done & have a good large stable library.