I was just looking at the Java bytecode and thinking "in theory, one could build a small JVM for this" [1]. But it still looks like an enormous effort to build, test and then use in a meaningful way.
IIRC, at the time, building on DOS w/djgpp was fully supported since leJOS is designed to be fairly OS independent. There's not much room for an OS in the Lego Mindstorms MCU. You can think of it a bit like how people today build minimal Rust or Go-lang OS experiments.
I was just looking at the Java bytecode and thinking "in theory, one could build a small JVM for this" [1]. But it still looks like an enormous effort to build, test and then use in a meaningful way.
[1] https://en.wikipedia.org/wiki/Java_bytecode_instruction_list...