We demonstrate here the use of JNA, the java native access library, with two simple functions:

• String doTheJobNative() which simply returns "it works!" from native side
• int doTheJobArrayNative(byte[] inputArray, int[] outputArray, int arraySize) which plays with array reading and writing

We use the "Direct Method Mapping" to optimize native calls duration.

Build and run

• build the native library (mac and linux are supported): (cd native-library/ && ./build-linux.sh)
• run the tests on java side: mvn clean install

NB: you need java 11 at least to get performance measures working (relies on Instant class)