I have published a Java version of the demo I described in this post on GitHub. Everything is the same only the language used for the implementation is changed to Java. So for a description please refer to the linked post.
Intro In this post I show how to combine some language / frameworks and libraries / tools to build a web-based scalable chat application. I chose the following combination of tools:
Kotlin as implementation language Vaadin for the web-based application Apache Kafka as the message backend Spring-Boot to get all together and running As I am bad in creating cool names for projects I just put together the first letters of the used tools and named this whole thing kovasbak.