in src/main/c/h3-java/src/jniapi.c [468:494]
JNIEXPORT void JNICALL Java_com_uber_h3core_NativeMethods_cellToLocalIj(
JNIEnv *env, jobject thiz, jlong origin, jlong h3, jintArray coords) {
CoordIJ ij = {0};
H3Error err = cellToLocalIj(origin, h3, 0, &ij);
if (err) {
ThrowH3Exception(env, err);
return;
}
jsize sz = (**env).GetArrayLength(env, coords);
jint *coordsElements = (**env).GetIntArrayElements(env, coords, 0);
if (coordsElements != NULL) {
// if sz is too small, we will fail to write all the elements
if (sz >= 2) {
coordsElements[0] = ij.i;
coordsElements[1] = ij.j;
}
// 0 is the mode
// reference
// https://developer.android.com/training/articles/perf-jni.html
(**env).ReleaseIntArrayElements(env, coords, coordsElements, 0);
} else {
ThrowOutOfMemoryError(env);
}
}