I can confirm that HotSpot is very aggressive at collapsing type hierachies and de-virtualising method calls. http://citeseerx.ist.psu.edu/viewdoc/download?doi

I can confirm that HotSpot is very aggressive at collapsing type hierachies and de-virtualising method calls. http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.117.2420&rep=rep1&type=pdf http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.117... This is one of the places where Java can outperform C++. Where c++ is unable to statically devirtualise method calls and HotSpot will just do it.