Is it discouraged using Java 8 parallel streams inside a Java EE container?

Question

Given that spawning threads in Java EE containers are discouraged. Would using the Java 8 parallel streams, which may spawn threads, inside Java EE be discouraged too?

Answer 1

EDIT See alternate answer from andrepnh. The below may have been the plan, but it doesn't appear to have played out that way in practice.

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The way I read it from the lambda-dev mailing list discussion mentioned in the comments: it's not discouraged the way spawning threads is - but won't do anything much for you in a Java EE context.

From the linked discussion:

the Java EE concurrency folks had been already talked through this, and the current outcome is that FJP will gracefully degrade to single-threaded (even caller-context) execution when running from within the EE container

So you're able to safely use parallel streams in a procedure or library that runs in both contexts. When it's run in a SE environment, it will make with the magical parallel shenanigans - but when it's run in an EE environment it will gracefully degrade to serial execution.

Note: the phrase quoted above is future tense - does anyone have a citation for some definitive documentation?