…yncHttpClient#2088)

Fixes AsyncHttpClient#2042 

This is a typical TOCTOU (time-of-check/time-of-use) race
https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use.
The NPE was occurring because the channel field could be set to null by
another thread between the check and its use:

if (channel != null) {                 // time-of-check
    Channels.setDiscard(channel);      //  time-of-use
    Channels.silentlyCloseChannel(channel);
}

By copying channel into a local variable in one atomic read, we ensure
that—even if another thread changes the field—the local reference
remains valid.

P.S. It is hard to write a deterministic test that fails consistently,
so this PR only includes the code fix.

---------

Co-authored-by: prat <[email protected]>

…ttpClient#2090)

Closes AsyncHttpClient#1884

---------

Co-authored-by: Copilot <[email protected]>

…0 in /client (AsyncHttpClient#2092)

Bumps org.apache.tomcat.embed:tomcat-embed-core from 10.1.39 to 10.1.40.


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