How to access arrays within an object with JNI?

Question

JNI tutorials, for instance this one, cover quite well how to access primitive fields within an object, as well as how to access arrays that are provided as explicit functio

Answer 1

In gcc 6.3 I get a warning saying "dereferencing type-punned pointer will break strict-aliasing rules" from a line like this:

jdoubleArray arr = *reinterpret_cast(&mvdata);

But since jdoubleArray is itself a pointer to class _jdoubleArray, there's no need to get the address before casting, and this static_cast works without warnings:

jdoubleArray arr = static_cast(mvdata);