Staying pure and functional with Spring 5

Room 1

Functional programming with immutables, monads and high order functions is not something that is common to java world. Java frameworks such as Spring seem to make this purity... impossible, especially with mutable beans, runtime context and aspects.

New version of Spring is a game changer here. With Spring Web Flux and project reactor we can actually create programs, webservers using almost only pure functional programming. Use of Kotlin and libraries such as Vavr makes such approach sensible alternative to the 'old style' in some projects.

Let me show You how it works on a real business case, with some interesting practices that may be interesting to you - even if you do not step into fully functional path.