On Mon, 10 Aug 2026 12:21:26 GMT, Jaikiran Pai <[email protected]> wrote:

> Can I please get a review of this change which proposes to implement the 
> enhancement requested in https://bugs.openjdk.org/browse/JDK-8371903?
> 
> HTTP/2 protocol allows endpoints to send a `GOAWAY` frame 
> https://www.rfc-editor.org/rfc/rfc9113.html#name-goaway. The `GOAWAY` frame 
> contains an error code which can be `0` (implying no error) or some other 
> code (implying some error). The `GOAWAY` frame is a signal to the peer that 
> the connection will (soon) be closed by the endpoint and no new requests 
> should be issued on it.
> 
> When a server sends a `GOAWAY`, the `HttpClient` implementation in the JDK 
> when processing that frame will (rightly) mark the connection as unusable for 
> new requests and if there are no active streams on that connection will 
> (rightly) close the connection. The HttpClient implementation will then 
> create new connection as and when needed for any subsequent requests.
> 
> In the case where the `HttpClient` receives the `GOAWAY` when there are 
> current active streams, then the implementation marks the connection as 
> unusable for new requests and just moves along. Depending on why the `GOAWAY` 
> was issued by the server, the server may either let the requests complete 
> normally or may close the connection before the requests complete. This can 
> then lead to the `HttpClient` rightly failing such requests. Such failures 
> get propagated to the application code as (subtypes) of `IOException`. All 
> this is expected and complies with the API specification of `HttpClient` as 
> well as the HTTP/2 protocol.
> 
> One detail of the `GOAWAY` frame is that the error code in that frame is 
> specified by the HTTP/2 protocol. These error codes have specific meaning and 
> sometimes can be a useful detail to include when a request is being failed 
> due to the connection being closed by the server. In the current 
> implementation of the `HttpClient`, this detail doesn't show up in the 
> stacktrace or exception message of the `IOException` that reaches the 
> application.
> 
> The changes in this PR enhance the implementation of `HttpClient` to keep 
> track of the error code from a `GOAWAY` frame and if some stream fails due to 
> a connection termination, then the error code from the `GOAWAY` is included 
> in the termination cause's exception message that reaches the application. In 
> the proposed implementation if a stream fails exceptionally, then we check 
> the exception type for `SocketException` and `EOFException` and if it is 
> either of these then we consider the `GOAWAY` frame's error as the cause of 
> th...

src/java.net.http/share/classes/jdk/internal/net/http/Http2Connection.java line 
2080:

> 2078:                         ? terminationCause
> 2079:                         : 
> Http2TerminationCause.inferFromGoAway(terminationCause,
> 2080:                         incomingGoAway.errorCode);

Given that the `incomingGoaway` variable is volatile and can be set outside of 
the `stateLock` we should really read it only once in the body of this method. 
Since we only read it, I would suggest something like:

    var  incomingGoaway = this.incomingGoaway;

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/32278#discussion_r3750197406

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