presto-main/src/main/java/io/prestosql/operator/ExchangeClient.java/ExchangeClientCallback/clientFailed
class ExchangeClientCallback:        @Override
        public void clientFailed(HttpPageBufferClient client, Throwable cause)
        {
            requireNonNull(client, "client is null");
            requireNonNull(cause, "cause is null");
            ExchangeClient.this.clientFailed(cause);
        }