@Override
            public AsyncDataConsumer handleResponse(
                    final HttpResponse response,
                    final EntityDetails entityDetails) throws HttpException, IOException {
                final HttpClientContext clientContext = scope.clientContext;
                if (entityProducer != null && !entityProducer.isRepeatable()) {
                    if (LOG.isDebugEnabled()) {
                        LOG.debug("{} cannot retry non-repeatable request", exchangeId);
                    }
                    return asyncExecCallback.handleResponse(response, entityDetails);
                }
                state.retrying = retryStrategy.retryRequest(response, scope.execCount.get(), clientContext);
                if (state.retrying) {
                    state.delay = retryStrategy.getRetryInterval(response, scope.execCount.get(), clientContext);
                    if (LOG.isDebugEnabled()) {
                        LOG.debug("{} retrying request in {}", exchangeId, state.delay);
                    }
                    return new DiscardingEntityConsumer<>();
                }
                return asyncExecCallback.handleResponse(response, entityDetails);
            }
Request executor in the asynchronous request execution chain that is
responsible for making a decision whether a request that failed due to
an I/O exception or received a specific response from the target server should
be re-executed.
<p>
Further responsibilities such as communication with the opposite
endpoint is delegated to the next executor in the request execution
chain.
</p>
<p>
If this handler is active, pay particular attention to the placement
of other handlers within the handler chain relative to the retry handler.
Use {@link ChainElement#RETRY} as name when referring to this handler.
</p>
<p>
If a custom handler is placed <b>before</b> the retry handler, the handler will
see the initial request and the final outcome after the last retry. Elapsed time
will account for any delays imposed by the retry handler.
</p>

<p>
A custom handler which is placed <b>after</b> the retry handler will be invoked for
each individual retry. Elapsed time will measure each individual http request,
without the delay imposed by the retry handler.
</p>

@since 5.0
httpclient5/src/main/java/org/apache/hc/client5/http/impl/async/AsyncHttpRequestRetryExec.java