Rust build
cd mylib
cargo build
Java build
cd java_src
javac me/ehlxr/HelloWorld.java
Java run
cd java_src
# Linux: export LD_LIBRARY_PATH=../mylib/target/debug/
# export JAVA_LIBRARY_PATH=../mylib/target/debug/
java -Djava.library.path=../mylib/target/debug/ me.ehlxr.HelloWorld