Workshop: Beginning RxJava




9:00am - 12:00pm


Own laptop with Java 8 development environment
Cloned GitHub project (will be announced later)
Familiarity with Java 8 lambda expressions

RxJava is a relatively new way of expressing and composing streams of data as well as asynchronous computations. You can find lots of tutorials related to various operators that RxJava provides. However we will focus on fundamental concepts in Rx like backpressure and hot vs. cold sources. This is a workshop for beginners so feel free to join if you have no experience whatsoever. There will be no slides and very little talking. Each and every participant will get a set of exercises in the form of unit tests to follow.

By the end of the workshop you will be capable of using RxJava safely and effectively in both greenfield and legacy projects. This will allow you to write expressive, thread-safe and well-performing code both on the server and on mobile devices. Also you will learn how to look for certain operators and understand their behavior.

Key Takeaways:

  • subscription mechanism and error propagation
  • hot vs. cold sources
  • declarative concurrency and threading
  • backpressure and flow control
  • unit testing

Speaker: Tomasz Nurkiewicz

Software Developer @4financeIT & Author of Reactive Programming with RxJava

Spent half of his life on programming, for the last decade professionally in Java land. Loves back-end, tolerates JavaScript. Passionate about alternative JVM languages. Disappointed with the quality of software written these days (so often by himself!), hates long methods and hidden side effects. Interested in charting, data analysis and reporting. Believes that computers were invented so that developers can automate boring and repetitive tasks. Also their own. On a daily basis works in financial sector. Involved in open-source, DZone’s Most Valuable Blogger, used to be very active on StackOverflow. Author, trainer, conference speaker, technical reviewer, runner. Claims that code not tested automatically is not a feature but just a rumour. Wrote "Reactive Programming with RxJava" for O'Reilly.

Find Tomasz Nurkiewicz at



Monday Nov 7

Tuesday Nov 8

Wednesday Nov 9