@Override
                        protected void start(
                                final HttpResponse response,
                                final ContentType contentType) {
                            System.out.println(request + "->" + new StatusLine(response));
                        }
Example of asynchronous HTTP/1.1 request execution with response streaming.
httpclient5/src/test/java/org/apache/hc/client5/http/examples/AsyncClientHttpExchangeStreaming.java