Kotlin and JNI example

How to get started ?

1. Create kotlin source files: Main.kt and NativeSample.kt. See files in src folder.

2. Notice in NativeSample.kt, I import "NativeSample" library. This is the name of my dll/so file. It should be changed to match your project.

3. Create native header file by running the following command: javah -jni -cp ".;path/to/kotlin-runtime.jar" sam.NativeSample

• Make sure javah is in your system path. More on javah
• sam.NativeSample is the class name that contains native calls.

4. Once the header file is generated (see jni/sam_NativeSample.h), you can create the implementation file for your header (see jni/sam_NativeSampleImp).

5. That is it. Follow the build/run instructions below.

Build Kotlin

Build and compile kotlin with Kotlin CLI. If you use IntelliJ, you can also use Kotlin plugin for compilation.

Build C/C++

Build and compile C/C++ source to SO/DLL library with Clang, GCC or Visual Studio.

Run program with JVM

One way to run the program is:

• navigating to build folder out/production/kolin-jni-example
• copy your native dll file to this directory.
• run java -cp ".;path/to/kotlin-runtime.jar" sam.SamPackage