“Sequenced Collections” with Stuart Marks

04/25/23 • 40 min

Sequenced Collections, targeted for JDK 21, are a new collection type created to represent a sequence of elements with a defined encounter order.

Ana recorded this episode with Stuart Marks, the owner of JEP 431 about Sequenced Collections. Stuart discusses the essence of Sequenced Collection interfaces, what needs those address and how they fit within the existing Collections framework. He explains the design of Sequenced Collections, architectural decisions and particularities of the API. He also shares his view on how Sequenced Collections can inspire future Java platform developments.

Sequenced Collections, targeted for JDK 21, are a new collection type created to represent a sequence of elements with a defined encounter order.

Previous Episode

"Preview Features: A Look Back and A Look Ahead" with Alex Buckley

Preview Features have been essential to the delivery of Java for the past 5 years, and Java 20 is no exception with second previews of both Virtual Threads and the Foreign Function & Memory API.

Chad discussing the importance of Preview Features with Alex Buckley, as well as an Informational JEP that added some further clarification for Preview Features with large surface areas.

Some show notes:

JDK 20 is out today: https://openjdk.org/projects/jdk/20/

JEP 12: Preview Features https://openjdk.org/jeps/12

A look ahead: https://openjdk.org/jeps/8300604

Next Episode

“The Panama Effect” with Jorn Vernee

The Foreign Function and Memory API will be finalised in JDK 22. This API helps you integrate native code within your Java program.

Using this new API you can efficiently invoke code outside the JVM, safely access memory not managed by the JVM, call native libraries and process native data without the brittleness and danger of JNI.

Jorn Vernee, core contributor and maintainer of the FFM API, is Ana’s guest during this episode. Jorn explains what is the Foreign Memory Access API, its goals and the iterations that this API went through. Jorn also shares a few examples of Java libraries that already adopted the FFM API, the performance improvements they observed. He also explains how you can use this new API to integrate a native library within your own Java code.