RFR: 8371903: HttpClient: improve handling of HTTP/2 GOAWAY frames with error code [v2]

[Daniel Jeliński]

On Wed, 10 Dec 2025 10:04:14 GMT, EunHyunsu <duke at openjdk.org> wrote:

>> Hi @laeubi, yes it's related to your report. The point of this PR is to bring HTTP2 on par with HTTP3, which throws an exception with a string message. Specialized exception can be handled as a future enhancement, but I'd like to see some evidence that it would be useful to users.
>
> @djelinski Fixed the intermittent test failures:
>   - Removed `close()` call after GOAWAY to avoid connection reset errors
>   - Server now relies on Http2TestServer for connection cleanup
>   - Tested 10 times locally, all passed
> 
>   Should be stable now. Please review when you get a chance

@ehs208  thanks for that, the test looks stable now.

Looking at the test logs, I realized why the `goAwaySentLatch.await` was where you originally had it; now that it's after all 3 requests, the requests are sent on 3 distinct connections, which is not what we want. Please move it back to its original position (after sending first request). Sorry for my confusion.

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PR Comment: https://git.openjdk.org/jdk/pull/28632#issuecomment-3637155681