In JavaOne 2026’s closing session, audience members had the opportunity to ask the Java architects questions. They asked about the state of structured concurrency and Project Babylon, how Java is being developed and the role AI plays in that process, the architects’ pet projects, and whether they would ever consider breaking backward compatibility, etc.

- John Rose's talk: https://youtu.be/J4O5h3xpIY8
- All https://www.youtube.com/playlist?list=PLX8CzqL3ArzUMVSzm-z_-if8BIB55EGl4 talks
- More IJP episodes: https://inside.java/podcast/


~~ Chapters ~~

0:00 intro
2:18 State of Structured Concurrency
4:35 State of Project Babylon
6:34 Feature Prioritization
12:56 Module Adoption
19:38 Stream API Performance Improvements
29:49 Module vs Class Path
33:42 Thoughts on Lombok
36:42 Object Header Size
37:16 Thoughts on a JDK Build Tool
39:38 "What Are Your Pet Projects?"
45:44 Use of AI Tooling in JDK Development
53:06 Advanced Hardware Information and Interaction
54:36 Breaking Backwards Compatibility
55:52 Next Generation of Java Developers

Tags: #Java #OpenJDK #Concurrency #AI #Performance #Coding #JavaOne

Java (Official Oracle)

A live Q&A session with Java architects at JavaOne 2026 covering a wide range of topics: the near-finalization of structured concurrency, Project Babylon's path to incubation, why the JDK doesn't simply adopt third-party libraries like Jackson, the slow adoption of the Java module system and build tool friction, Java's stance on Lombok (considered a bad citizen for hacking compiler internals), Stream API performance trade-offs and potential future improvements via Valhalla and Babylon, the possibility of a JDK-owned build tool, AI usage in JDK development, and Java's strong commitment to backwards compatibility.

Module Adoption? JDK Build Tool? Lombok? Backwards Compatibility? - Ask the Architects at JavaOne'26