It seems like your use case is rather not a good fit for Java.
Java shines best with large applications, where more abstract source code is desired and when you care more about typical performance, not the worst case performance. And if you can afford the cost of all those benefits, which is higher RAM usage.
At least that's the theory :)
I mean, I've been writing JVM based software for 27 years now, but it was written for a different world (that never came), and it just isn't a perfect fit for most of our needs any more.
Companies like PTC and Aicas stay in business, because there are plenty of industries that pay for their embedded JVM implementations instead of keeping legacy C and C++ infrastructure running.
The JVM is amazing technology for what it is, but what it is still limits how fast it can go.
When you can get the benefits and let the LLMs pay for the downsides you'd otherwise have to handle - that's a change of circumstances that we really ought to pay attention to as software devs.
Can you write very fast Java software, yes - LMAX is a great example. Can you write slow Rust/C++ code, absolutely. But the values, community and tech built around the latter really does make it a lot easier when that's your (and your LLM's) goal.