What is the best way to start Scala code from SpringBoot Web App?

Question

Java

Hello, please tell me if it is possible to somehow better organize the project. The fact is that I have a SpringBoot Web App - which, after processing the request, calls the Scala code.
Now communication is organized through API. And, accordingly, I have one project of 3 Web <-> API <-> Scala modules. Both Java and Scala code compiles and boots with SpringBoot.
So, I would like to separate Java and Scala projects, but the question is - how best to organize communication? So that there are no delays in launching and so on.
I would be grateful for advice and ideas.
Thank you!