Github user zentol commented on a diff in the pull request: https://github.com/apache/flink/pull/5038#discussion_r152298240 --- Diff: flink-queryable-state/flink-queryable-state-client-java/src/main/java/org/apache/flink/queryablestate/network/Client.java --- @@ -312,32 +345,43 @@ private void handInChannel(Channel channel) { /** * Close the connecting channel with a ClosedChannelException. */ - private void close() { - close(new ClosedChannelException()); + private CompletableFuture<?> close() { + return close(new ClosedChannelException()); } /** * Close the connecting channel with an Exception (can be {@code null}) * or forward to the established channel. */ - private void close(Throwable cause) { - synchronized (connectLock) { - if (!closed) { - if (failureCause == null) { - failureCause = cause; - } + private CompletableFuture<?> close(Throwable cause) { + CompletableFuture<?> future = new CompletableFuture<>(); + if (connectionShutdownFuture.compareAndSet(null, future)) { + synchronized (connectLock) { + if (!closed) { --- End diff -- this seems unnecessary, doesn't the check at L358 guarantee that the entire branch is only executed once?
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