Ah, I never expected people to use the socket connections locally, the system was made with a client-server configuration in mind, although using it for local data communication should work just as well.
I’ve added a blueprint to the Socket Connection plugin to choose a custom buffer size, that will hopefully fix any limitations when using the plugin for local data communication.
Do note though that each latent blueprint (a blueprint with a stopwatch/clock in its top-right corner) will never complete in the same frame they are called, and so they will always takes at least 1 frame to complete. This is because UE4 only starts ticking latent blueprints at the start of the next frame.
Anyways, I’d love to see your project work, I think it would be very interesting, cool and especially funny to see all logic being done in Java on the same machine.