I think you've got yourself confused. The heap is what malloc is allocating. So it's like you said "Surely this is somewhere in Europe, not France?" or "Surely this is a round shape, not a circle?"
https://github.com/openjdk/jdk/blob/master/src/hotspot/share...
https://en.wikipedia.org/wiki/List_of_Java_virtual_machines
And the list doesn't include all, e.g. PTC (https://www.ptc.com/en/products/developer-tools/perc)