After the structured concurrency API saw a big revamp in JDK 25, 26 is refining that new version and sending it out for another preview with a few small changes, most of them to the `Joiner` interface:

* it can now implement `onTimeout` and thus do some cleanup and define what exception should be thrown in that case
* `allSuccessfulOrThrow()` now returns a list of results rather than a stream of subtasks
* `anySuccessfulResultOrThrow()` dropped "result" from its name and it's now just `anySuccessfulOrThrow()`

As with all preview language features and APIs, if you want them sooner rather than later, the best way to get them to finalize is to try them out in as close to a production environment as you can and give feedback on the respective mailing list with what worked well for you and what didn't.

JEP 526: https://openjdk.org/jeps/525
JDK 26: JDK 26: http://jdk.java.net/26

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Java (Official Oracle)

Java 26 is refining the Structured Concurrency API introduced in JDK 25, sending it out for another preview with small but notable changes to the `Joiner` interface. Key updates include: `onTimeout` support for cleanup and custom exception handling, `allSuccessfulOrThrow()` now returns a list instead of a stream of subtasks, and `anySuccessfulResultOrThrow()` has been renamed to `anySuccessfulOrThrow()`. Developers are encouraged to test these preview features in near-production environments and provide feedback on the mailing list to help finalize the API.

Structured Concurrency in #Java 26 #IJN #Coding