Support

Kreate provides first-class support for integrating native C/C++ code into JVM projects via the Java Native Interface (JNI). The entire build pipeline — from project scaffolding to CMake compilation and runtime library resolution — is automated through a set of dedicated Gradle tasks.

JNI support was introduced in Kreate 1.1.0 and lives inside the platform.jvm.jni DSL block.

How It Works

When JNI is enabled, Kreate registers and wires up the following automatically:

kreate-jni-initialize — Scaffolds the native C++ project structure if it does not exist yet
kreate-jni-build — Configures and builds the shared library via CMake (cmake -S . -B build → cmake --build)
Compile hook — kreate-jni-build runs before every Kotlin compilation task so the native library is always up to date
Runtime path — All Test and JavaExec tasks receive -Djava.library.path pointing to the CMake build output directory

Prerequisites

CMake 3.20 or later
A C++17 capable compiler (GCC, Clang, or MSVC)
JDK with JNI headers (included in any standard JDK installation)

Project Layout

A JNI-enabled module follows this directory convention:

my-module/
├── build.gradle.kts
├── src/                        # Kotlin sources
└── jni/                        # JNI root (default, configurable)
    └── <projectName>/
        ├── CMakeLists.txt      # Generated on first run if missing
        └── src/
            └── <projectName>.cpp   # Placeholder generated on first run

The layout mirrors the C-Interop convention used for Rust projects, keeping native source structures consistent across both features.

Next Steps

Configuration: DSL reference and all available options
Project Scaffolding: How the kreate-jni-initialize task works
Build Pipeline: CMake build and runtime library path wiring

26 April 2026