Java modules in practice with Spring Boot

Java Modules have been around for a little while now and most of us know deep inside that we need start doing something with them. Yet most developers are waiting for the momentum to take off. You’ve probably heard the theory a couple of times already, but putting it into practice sounds like mom forcing you to eat your veggies. Actually, I love my veggies, so I’ll gladly help you out here. In this session I will demonstrate how you can start using the power of modules in your own application. A Spring Boot application. Because despite the adoption in libraries is not yet great, you can already perfectly make your own application modular. I will guide you through a step-by-step approach to making your application modular. No magic or module-fu is required to achieve this result. Just everyday technologies we have at our disposal in the Java ecosystem. And as a bonus, it even works with Kotlin….

Transcript

1. Jaap Coomans @JaapCoomans Java Modules in practice with Spring Boot
2. @JaapCoomans Jaap Coomans Developer / Software Architect Java since 2002 Tilburg, The Netherlands Father, husband Boardgame player about:me
3. JPMS: CURRENT STATE OF AFFAIRS
4. JPMS: CURRENT STATE OF AFFAIRS Tool support: good
5. JPMS: CURRENT STATE OF AFFAIRS Tool support: good Framework and library adoption: low
6. JPMS: CURRENT STATE OF AFFAIRS Tool support: good Framework and library adoption: low Developer adoption: very low
7. JPMS: CURRENT STATE OF AFFAIRS Tool support: good Framework and library adoption: low Developer adoption: very low What’s holding us back?
8. It’s like eating your veggies…
9. It’s like eating your veggies… But… we like our veggies!
10. BUT
11. main repositories rest-api controllers services legacy legacy- framework A TALE OF MISFORTUNE
12. main repositories rest-api controllers services legacy legacy- framework A TALE OF MISFORTUNE
13. main repositories rest-api controllers services legacy legacy- framework A TALE OF MISFORTUNE
14. https://www.flickr.com/photos/nasacommons/20264606661 What challenges will we face?
15. SPLIT PACKAGES SPLIT PACKAGES
16. Automatic Modules https://commons.wikimedia.org/wiki/File:Roborally_boardgame.JPG Author: Moroboshi
17. AUTOMATIC MODULES
18. AUTOMATIC MODULES Exports and opens all packages
19. AUTOMATIC MODULES Exports and opens all packages Reads all other modules
20. AUTOMATIC MODULES Exports and opens all packages Reads all other modules Module name derived from filename
21. AUTOMATIC MODULES Exports and opens all packages Reads all other modules Module name derived from filename Automatic-Module-Name
22. What will we build? Author: Yonghokim https://commons.wikimedia.org/wiki/File:A_game_of_Settlers_of_Catan.jpg
23. application rest-api domain persistence security bgg-client OpenFeign JJWT JAX-B
24. application rest-api domain persistence security bgg-client OpenFeign JJWT JAX-B
25. Step 1 Upgrade your dependencies https://commons.wikimedia.org/wiki/File:Funkenschlag-detail2.jpg Author: Matěj Baťha
26. Step 2 Run with JDK11+ Author: Nodens77 https://boardgamegeek.com/image/762747/el-grande Author: Jérémie Bryon
27. Step 3 Compile with JDK11+ https://boardgamegeek.com/image/273748/union-pacific Author: Mark Hamburg
28. Step 4 Prepare module structure https://boardgamegeek.com/image/213002/saint-petersburg Author: Ross G. (ZiggyZambo)
29. Step 5 Add descriptors bottom-up https://boardgamegeek.com/image/3158665/castles-mad-king-ludwig Author: Steph Hodge
30. Step 6 Add descriptor to main jar https://boardgamegeek.com/image/2053387/camel Author: Tomasz Miedzik
31. Bonus round:
32. LESSONS LEARNED
33. LESSONS LEARNED GO BOTTOM UP
34. LESSONS LEARNED Test all paths on every step GO BOTTOM UP
35. LESSONS LEARNED The logs have the answer Test all paths on every step GO BOTTOM UP
36. LESSONS LEARNED It still involves pioneering The logs have the answer Test all paths on every step GO BOTTOM UP
37. Game over… Get the code: Contact me: https://github.com/jaapcoomans/spring-boot-modules @JaapCoomans jaap.coomans@group9.nl