io_uring will indeed be a perfect fit for Java: no need to pay a supplemental JNI access cost for each IO as all you need is a memory barrier to read or write the shared queues which can be properly implemented in pure Java. We're not there yet but here is where you can look:

- For network I/O, Netty has an incubating transport that is promising [1].

- For disk I/O, JDK's Loom project [2] has mentioned its plan to rely on io_uring on Linux [3], but there's no ETA AFAIK.

[1] https://github.com/netty/netty-incubator-transport-io_uring

[2] https://openjdk.org/projects/loom/

[3] https://cr.openjdk.org/~rpressler/loom/loom/sol1_part1.html