Fully Reactive: Spring, Kotlin, and JavaFX Playing Together

Spring Framework 5 brings full reactive support to developers everywhere. What better way to demo reactive programming than to actually build something live? Trisha will live code an end-to-end application using Spring Framework 5, Spring Boot, Reactor, Kotlin, JavaFX, and maybe even some MongoDB, all built using IntelliJ IDEA. During this session, we’ll see how these different components can work together really easily using Spring. What could possibly go wrong?

I also gave this presentation for the vJUG (video), which is a little shorter and it does miss out the RSocket functionality.


I've split the demo into much smaller pieces in order to make it easier to follow along with. Each step consists of a video of 5-10 mins and a blog post which explains the process and contains the code from the video.

All steps in the Tutorial


The code may be slightly different from the demo, as the demo needs to simplify the process of creation and I get to take my time when I'm creating the real app! This is the code for the application as I created it, before I demoed it:

This is the exact code created for the IntelliJ IDEA tutorial, which may differ slightly:


I Googled a LOT for this demo, and that was even after Josh and I had already presented it at Code One in 2018!

Spring & Spring Boot

REST & Reactive Web


Reactive Testing




  • Trisha Gee

    Trisha is a software engineer, Java Champion and author. Trisha has developed Java applications for finance, manufacturing and non-profit organisations, and she's a lead developer advocate at Gradle.