// This is pseudo code, but it gives you an idea of how v8<->JNI might work

static JavaVM *vm;

// Called when the shared library is loaded
extern "C" JNIEXPORT jint JNICALL
JNI_OnLoad(JavaVM *jvm, void *reserved)
{
	JNIEnv *env;
	vm = jvm; /* cache the JavaVM pointer */

	if (jvm->GetEnv((void **) &env, JNI_VERSION_1_4)) {
		return JNI_ERR; /* JNI version not supported */
	}
	return JNI_VERSION_1_4;
}

jclass objClass;
jmethodID javaMethodId;

// V8Main.main(src, name);
extern "C" JNIEXPORT void JNICALL
Java_org_appcelerator_kroll_v8_V8Main_main(JNIEnv *env, jobject thiz, jstring source, jstring name)
{
	HandleScope scope;
	Handle<ObjectTemplate> globalTemplate = ObjectTemplate::New();
	Persistent<Context> context = Context::New(NULL, globalTemplate);
	Context::Scope contextScope(context);

	// Object templates are the way v8 exposes prototypes natively
	// Any object that is created w/ the template has the APIs on the template itself
	Handle<ObjectTemplate> objTemplate = ObjectTemplate::New();

	// To bind a java method, we would first bind a native function pointer
	objTemplate->Set(String::New("javaMethod"), Obj_javaMethod);

	Handle<Object> obj = objTemplate->NewInstance();
	// We wrap the "thiz" pointer into an internal field so it can be fetched
	obj->SetInternalField(0, External::Wrap(reinterpret_cast<void*>(thiz)));

	// Cache the class, and "javaMethod" methodID for later
	objClass = env->FindClass("com/my/Class");

	// javaMethod() is a void method
	javaMethodId = env->GetMethodID(objClass, "javaMethod", "()V");

	// Finally bind "obj" as "helloWorld" in JS land
	context->Global()->Set(String::New("helloWorld"), obj);

	const char *srcData = const_cast<const char *>(env->GetStringUTFChars(source, NULL));
	const char *cName = const_cast<const char *>(env->GetStringUTFChars(name, NULL));

	Local<Script> script = Script::Compile(String::New(srcData), String::New(cName));
	script->Run();

	env->ReleaseStringUTFChars(source, srcData);
	env->ReleaseStringUTFChars(name, cName);
	context.Dispose();
}

static Handle<Value> Obj_javaMethod(const Arguments& args)
{
	// get the java pointer
	jobject obj = reinterpret_cast<jobject>(External::Unwrap(args.This()->GetInternalField(0)));

	// get the JNIEnv
	JNIEnv *env;
	vm->GetEnv((void **) &env, JNI_VERSION_1_4);

	env->CallVoidMethod(obj, javaMethodId);
	return Undefined();
}

## test.js

helloWorld.javaMethod();