kotlin dependencies { implementation "com.icecreamshoedev:injekt-core:<version>" } kotlin fun JavaClass.extensionFunction() { } kotlin import dev.icecreamshoe.injekt.Injekt fun main() { Injekt.initialize() Injekt.addExtension(JavaClass::class, ::extensionFunction) Injekt.shutdown() } kotlin fun main() { val javaObject = JavaClass() javaObject.extensionFunction() }