static jint CameraMetadata_getEntryCount(JNIEnv *env, jobject thiz) {
    ALOGV("%s", __FUNCTION__);

    CameraMetadata* metadata = CameraMetadata_getPointerThrow(env, thiz);

    if (metadata == NULL) return 0; // actually throws java exc.

    return metadata->entryCount();
}
static jboolean CameraMetadata_isEmpty(JNIEnv *env, jobject thiz) {
    ALOGV("%s", __FUNCTION__);

    CameraMetadata* metadata = CameraMetadata_getPointerThrow(env, thiz);

    if (metadata == NULL) {
        ALOGW("%s: Returning early due to exception being thrown",
               __FUNCTION__);
        return JNI_TRUE; // actually throws java exc.
    }

    jboolean empty = metadata->isEmpty();

    ALOGV("%s: Empty returned %d, entry count was %zu",
          __FUNCTION__, empty, metadata->entryCount());

    return empty;
}