How exactly does knowing it's an insurance/finance application magically change the answer to "how to get my head around 100m lines of Java code"? Is there some "financial java code analysis" tool or technique that's so completely distinct from "engineering java code analysis" or "healthcare java code analysis" that it deserves a snotty, condescending retort?
An 'Ask HN' with this level of input is not a guessing game where the people that try to help have to play 'bingo' with the asker for information that may or may not be important for the answer. If there is context available and the asker is free to talk about that context then it should be supplied up-front.
There is nothing snotty or condescending about that, but there is something very weird about this whole thread, I wished I could put my finger on it.