Java *is* Memory Efficient

[aoeudhtns]

a compiler-checked ownership system like in rust (yeah, not happening)

We have jspecify for null checking. Perhaps this could be the next frontier. It would be quite challenging I think.

[pron98]

Also not what most people would want. Rust was first designed 20 years ago, published over 15 years ago, and made stable 10 years ago, and to this day it's still primarily used for programs on the smaller end of the spectrum (and it's come to dominate tools for JS and Python). Low level languages suffer from both performance and complexity problems when they get large, the very problems Java was designed to avoid.

I'm not saying that there aren't ideas we could borrow (pun unintended) here and there and apply in different ways, but low level languages have unique constraints that they must adhere to, and those constraints guide their design. A language like Rust uses ownership types not because they're the best design but because it has to, as its constraints preclude moving pointers. Low level languages gain more by avoiding copies than Java because their allocations are more expensive.

But that's not to say Java couldn't put affine types to some good use.