Migrating a Java application using 2.9 to 3.1.0

[jlweb58]

Hello, as I mentioned in the introduction thread, I currently have a backend using the old (2.9) library in a Java 21 application using JNI. I would like to migrate to 3.1.0. So far I was able to update my application to use Java 25, install Bazelisk on my Ubuntu VM, and build the application via bazelisk build //jni:dds_shared.

I'm a little unclear as to my next steps - can I just drop in the new libdds.so in place of the old library, without changing my JNA stubs?

[tameware]

I'm not using Java. My hope is yes - we've intentionally not changed the Application Binary Interface.

[jlweb58]

Wow, that was a quick answer! And I can already return the favor - I just made the switch locally, and everything seems to be working fine. I haven't run any performance benchmarks yet...

[jlweb58]

I'm running a quick and dirty performance benchmark now. My scenario:

• Provide a hand pair (single dummy analysis)
• Using a Monte Carlo algorithm and generating 1000 opposing hand pairs, calculate the success probability of a given contract.

[jlweb58]

Running this scenario 5 times with the 2.9 library on a local Ubuntu VM:
Mean: 31710 ms
Max: 33913 ms
Min: 28646 ms

Repeating with the same hand and the 3.1 library:
Mean: 26644 ms
Max: 28615 ms
Min: 24364 ms

To me that looks like a significant improvement (if not completely rigorously benchmarked). I think I will roll it out to production!