Well, is there a high-performance graph library for working with primitivies, without those generics/autoboxing overheads? For double lists you may use trove, for linear algebra you may use netlib-java (examples for you to better understand the point of my interest in this question).
As for Graphs/Networks: all the libs I've found use generics and should be not that performant. I may as well do some tests for that, but I believe that heap-managed network link weights would be inferior to double with some bit offsets to get the index for i and j. The usage scenario: there're hundreds of such networks (most of them sparse) of size 4k*4k, there's some genetic optimization running over that set of networks, which do some flow/min route estimations for each specimen.
So, there're: JGraphT, JUNG, ANNAS (the links lead to the APIs/code samples which expose the miserable Java Generics in all of them). Are there any Trove-ish alternatives? I'd already created some simplistic implementation, but just decided to look around to avoid inventing the proper bicycle...
PS: Please don't start on performance of generics-laden Java code, at least without linking to some decent benchmark, ok? ;)
© me @ SOSome trolling was spiced in, but let's see how StackOverflow users will respond to that... :)