"Immutable Data Beyond Value Classes" [AtA]

Object-Oriented Programming offers a lot of flexibility for modelling diverse domains but not all elements need that flexibility. Data, specifically, is often better modeled by simple, immutable types and while OOP does not prevent that, it can make it a bit cumbersome. So in recent and coming years, Java has gained and will gain a number of features that improve the situation: From flexible constructor bodies to records and value classes, from withers to lazy constants, and more - they all stand on their own, but they also come together to allow us to more expressively and elegantly define, construct, copy, and access immutable data.

In this "Ask the Architects" episode of the Inside Java Podcast, recorded during JavaOne 2026, Nicolai Parlog talks to Dan Smith, contributor to projects Amber and Valhalla and Senior Java Platform Developer at Oracle.

Show Notes:

• Better Tools for Immutable Data: https://www.youtube.com/watch?v=BdLND9D81lI
• JEP 513: Flexible Constructor Bodies: https://openjdk.org/jeps/513
• JEP 401: Value Objects (Preview): https://openjdk.org/jeps/401
• JEP 468: Derived Record Creation (Preview): https://openjdk.org/jeps/468
• JEP 547: Lazy Constants (Fourth Preview): https://openjdk.org/jeps/547