Linux

A null does not make it memory unsafe. You aren't accessing invalid memory, the runtime just raises a NRE. Which is fine. No memory safety violated.

Java is, as long as you stick to pure java and not native interop, entirely memory safe. And that's achieved by giving up control of memory allocation to the garbage collector.

Rust is not the first memory safe language. It does however, manage to achieve memory safety without needing a garbage collector. Which is what drew my initial interest.