public CompletableFuture discover()

in sdk/src/main/java/software/amazon/awssdk/iot/discovery/DiscoveryClient.java [77:124]
47 lines of code
5 McCabe index (conditional complexity)

    public CompletableFuture<DiscoverResponse> discover(final String thingName) {
        if(thingName == null) {
            throw new IllegalArgumentException("ThingName cannot be null!");
        }
        return CompletableFuture.supplyAsync(() -> {
            try(final HttpClientConnection connection = httpClientConnectionManager.acquireConnection().get()) {
                final String requestHttpPath =  "/greengrass/discover/thing/" + thingName;
                final HttpHeader[] headers = new HttpHeader[] {
                        new HttpHeader("host", httpClientConnectionManager.getUri().getHost())
                };
                final HttpRequest request = new HttpRequest("GET", requestHttpPath, headers, null);
                //we are storing everything until we get the entire response
                final CompletableFuture<Integer> responseComplete = new CompletableFuture<>();
                final StringBuilder jsonBodyResponseBuilder = new StringBuilder();
                final Map<String, String> responseInfo = new HashMap<>();
                try(final HttpStream stream = connection.makeRequest(request, new HttpStreamResponseHandler() {
                        @Override
                        public void onResponseHeaders(HttpStream stream, int responseStatusCode, int blockType, HttpHeader[] httpHeaders) {
                            Arrays.stream(httpHeaders).forEach(header -> {
                                responseInfo.put(header.getName(), header.getValue());
                            });
                        }
                        @Override
                        public int onResponseBody(HttpStream stream, byte bodyBytes[]) {
                            jsonBodyResponseBuilder.append(new String(bodyBytes, StandardCharsets.UTF_8));
                            return bodyBytes.length;
                        }
                        @Override
                        public void onResponseComplete(HttpStream httpStream, int errorCode) {
                            responseComplete.complete(errorCode);
                        }})) {
                    stream.activate();
                    responseComplete.get();
                    if (stream.getResponseStatusCode() != 200) {
                        throw new RuntimeException(String.format("Error %s(%d); RequestId: %s",
                                HTTP_HEADER_ERROR_TYPE, stream.getResponseStatusCode(), HTTP_HEADER_REQUEST_ID));
                    }
                    final String responseString = jsonBodyResponseBuilder.toString();
                    return GSON.fromJson(new StringReader(responseString), DiscoverResponse.class);
                } catch (InterruptedException | ExecutionException e) {
                    throw new RuntimeException(e);
                }
            }
            catch(InterruptedException | ExecutionException e) {
                throw new RuntimeException(e.getMessage(), e);
            }
        }, executorService);
    }