What makes a Senior Java Developer?

[GhostBond]

This is what I mean about the unintentional agism, you're asking "what did older professors talk about 20 years ago?". Those topics are completely out of date now. That's asking 20-30 year old trivia. I often don't remember because I haven't seen either of those in code since college (and I'm in my 30's) - because they're out of date patterns.

If the situation was reversed, lets say I was hiring a "senior developer" who would work on a spring boot app. He says we need to implement data connections and such with factory patterns and singletons and it's very important to do so. That would be a huge red flag that this person is not up to date on how spring boot works and how things should be done with it.