public ClassicHttpResponse execute()

in httpcore5/src/main/java/org/apache/hc/core5/http/impl/io/HttpRequestExecutor.java [119:200]
79 lines of code
20 McCabe index (conditional complexity)

    public ClassicHttpResponse execute(
            final ClassicHttpRequest request,
            final HttpClientConnection conn,
            final HttpResponseInformationCallback informationCallback,
            final HttpContext context) throws IOException, HttpException {
        Args.notNull(request, "HTTP request");
        Args.notNull(conn, "Client connection");
        Args.notNull(context, "HTTP context");
        try {
            context.setAttribute(HttpCoreContext.SSL_SESSION, conn.getSSLSession());
            context.setAttribute(HttpCoreContext.CONNECTION_ENDPOINT, conn.getEndpointDetails());

            conn.sendRequestHeader(request);
            if (streamListener != null) {
                streamListener.onRequestHead(conn, request);
            }
            boolean expectContinue = false;
            final HttpEntity entity = request.getEntity();
            if (entity != null) {
                final Header expect = request.getFirstHeader(HttpHeaders.EXPECT);
                expectContinue = expect != null && HeaderElements.CONTINUE.equalsIgnoreCase(expect.getValue());
                if (!expectContinue) {
                    conn.sendRequestEntity(request);
                }
            }
            conn.flush();
            ClassicHttpResponse response = null;
            while (response == null) {
                if (expectContinue) {
                    if (conn.isDataAvailable(this.waitForContinue)) {
                        response = conn.receiveResponseHeader();
                        if (streamListener != null) {
                            streamListener.onResponseHead(conn, response);
                        }
                        final int status = response.getCode();
                        if (status == HttpStatus.SC_CONTINUE) {
                            // discard 100-continue
                            response = null;
                            conn.sendRequestEntity(request);
                        } else if (status < HttpStatus.SC_SUCCESS) {
                            if (informationCallback != null) {
                                informationCallback.execute(response, conn, context);
                            }
                            response = null;
                            continue;
                        } else if (status >= HttpStatus.SC_CLIENT_ERROR){
                            conn.terminateRequest(request);
                        } else {
                            conn.sendRequestEntity(request);
                        }
                    } else {
                        conn.sendRequestEntity(request);
                    }
                    conn.flush();
                    expectContinue = false;
                } else {
                    response = conn.receiveResponseHeader();
                    if (streamListener != null) {
                        streamListener.onResponseHead(conn, response);
                    }
                    final int status = response.getCode();
                    if (status < HttpStatus.SC_INFORMATIONAL) {
                        throw new ProtocolException("Invalid response: " + new StatusLine(response));
                    }
                    if (status < HttpStatus.SC_SUCCESS) {
                        if (informationCallback != null && status != HttpStatus.SC_CONTINUE) {
                            informationCallback.execute(response, conn, context);
                        }
                        response = null;
                    }
                }
            }
            if (MessageSupport.canResponseHaveBody(request.getMethod(), response)) {
                conn.receiveResponseEntity(response);
            }
            return response;

        } catch (final HttpException | IOException | RuntimeException ex) {
            Closer.closeQuietly(conn);
            throw ex;
        }
    }