RFR: 8355726: LinkedBlockingDeque fixes and improvements

[kabutz]

On Thu, 8 May 2025 08:33:06 GMT, Viktor Klang <vklang at openjdk.org> wrote:

> I'm a bit uneasy about incrementing the `count` in `linkFirst` but not enforcing the invariant. What's the benefit to changing linkFirst and linkLast to return void instead of keeping the original returning a boolean?

I based the approach on the LBQ enqueue() and dequeue() methods, which also return void and have a comment with the assertion.

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PR Review Comment: https://git.openjdk.org/jdk/pull/24925#discussion_r2079757838