1/27/25 - JChampionsConf - TDD: It's easier than you think!

Everyone loves writing tests, don’t they? How do you write good tests? What tools are available for you to write good tests?

In this session, I will dive into the many features of Quarkus that help developers write good tests. I will highlight some of the features of Quarkus, Dev Services and Continuous Testing, which help make testing easier. Additionally, I will live code some tests for common use cases developers encounter, including unit, integration, and “black box” testing of imperative and reactive RESTful and event-driven applications that use common services, such as databases and Kafka brokers. I will discuss techniques such as mocking, spying, and interaction-based testing/verification.

I'll even spend some time showing how IDE-based AI assistants can help!

Once you see how easy TDD really can be there isn't a reason to not do it!

Transcript

1. TDD It’s easier than you think! Eric Deandrea Sr. Principal Developer Advocate @ Red Hat @edeandrea
2. Who am I? • 25+ years software development experience ◦ ~11 years as DevOps Architect in financial services / insurance Java Champion • Contributor to Open Source Projects Quarkus Spring Boot, Spring Framework, Spring Security LangChain4j (& Quarkus LangChain4j) Wiremock Microcks • Boston Java Users ACM Chapter Board Member • Published author • Avid boater & black belt in martial arts @edeandrea
3. https://red.ht/quarkus-spring-devs • Showcase & explain Quarkus, how it enables modern Java development & the Kubernetes- native experience • Introduce familiar Spring concepts, constructs, & conventions and how they map to Quarkus • Equivalent code examples between Quarkus and Spring as well as emphasis on testing patterns & practices 3
4. Why are we here today?
16. https://x.com/holly_cummins/status/1788138252572004441
18. But first, Some basics
20. end-to-end tests high realism high value
21. end-to-end tests unit tests low effort high realism high value
22. end-to-end tests unit tests integration tests low effort high realism high value
23. end-to-end tests unit tests integration tests low effort high realism
24. end-to-end tests unit tests integration tests low effort high realism tests with application server test REST endpoints tests with a database
25. @edeandrea
26. Today’s challenge
27. Pet Adoption Application HTTP (REST) adoptions topic adoption-requests topic Get / Persist pet info @edeandrea
28. https://bit.ly/tdd-easy
30. Additional resources
31. Kubernetes Native Java with Quarkus https://www.infoq.com/articles/native-java-quarkus Deployment Developer Joy • Quickly & easily build Kubernetes-Native Java applications • Industry leader in startup time and memory utilization for native and JVM applications • One step native executable generation • Leverage existing Java, Jakarta, MicroProfile, & Spring expertise • Imperative & reactive APIs side-by-side • Live coding with zero config @edeandrea
32. https://www.oreilly.com/library/view/reactive-systems-in/9781492091714 https://developers.redhat.com/e-books/understanding-quarkus https://developers.redhat.com/e-books/practising-quarkus @edeandrea
33. https://quarkus.io/blog/quarkus-superheroes-to-the-rescue https://github.com/quarkusio/quarkus-super-heroes Quarkus Superheroes
34. https://quarkus.io @quarkusio https://quarkus.io/community
35. Thank you!