jclass clazz = env->FindClass(kClassPathName);
if (clazz == NULL) {
    return;
}

fields.context = env->GetFieldID(clazz, "mNativeContext", "I");
if (fields.context == NULL) {
    return;
}

java.lang.NoSuchFieldError: no "I" field "mNativeContext" in class "Lcom/test/NativeLibrary;" or its superclasses