[jax-rs-spec users] Re: Server-Sent Events API proposal

From: Pavel Bucek <>
Date: Wed, 1 Feb 2017 16:15:12 +0100

Hi Alessio,

please see inline.

On 01/02/2017 15:29, Alessio Soldano wrote:
> Il 24/01/2017 20:54, Pavel Bucek ha scritto:
>> The API was introduced a while back [1], but we did incorporate some
>> changes, mostly alignments with Java SE 8 and another one, slightly
>> more controversial - alignment with Java SE 9 Flow API.
>> Why we should use Flow API? We want to make the transition to Java 9
>> as smooth as possible. Please note that today, the JAX-RS sources do
>> contain Flow class (1:1 copy from Java SE 9), but that is NOT a final
>> state. We want to work with it as much as possible, but we will
>> minimize and clean up the code before final release. How? Consider
>> following example:
>> public interface SseBroadcasterextends AutoCloseable, Flow.Publisher<OutboundSseEvent> {
>> //...
>> }
>> could be modified to
>> public interface SseBroadcasterextends AutoCloseable {
>> //...
>> void subscribe(SseSubscriber<?super OutboundSseEvent> subscriber);
>> }
>> I hope you will like the attempt to be "forward-compatible", but I
>> assume that this proposal alone will bring some opinions - please
>> share them!
> Just as a confirmation, so basically the idea is to keep this copy of
> the Flow api in jaxrs api snapshots for now to prove we'll eventually
> be able to use the real Flow interface from java 9 and actually modify
> the jaxrs api (removing the Flow copy, etc) just before going final?
JAX-RS 2.1 will be based in Java SE 8 (as the rest of Java EE 8), so we
cannot depend on the actual class from Java SE 9 yet. But what we can do
is to craft the API in a way when we can easily extend / implement Flow
APIs in JAX-RS which will be part of Java EE 9 (running on Java SE 9).

- Flow class, which is currently in place, will be removed
- All usages of that will be refactored. It could mean only declaring
some methods (like SseBroadcaster) or introducing new Interfaces
- When Java EE 9 is released, JAX-RS classes/interfaces should be
modified to extend java.util.concurrent.Flow.* where applicable

Current state:

public interface SseBroadcasterextends AutoCloseable,<OutboundSseEvent> {

JAX-RS 2.1 release:

public interface SseBroadcasterextends AutoCloseable {
void subscribe(SseSubscriber<?super OutboundSseEvent> subscriber);


public interface SseBroadcasterextends AutoCloseable, java.util.concurrent.Flow.Publisher<OutboundSseEvent> {

> Besides that, as a general feedback, I think the latest additions to
> the sse api are fine.

great, thank you!

Best regards,