2 * ============LICENSE_START=======================================================
4 * ================================================================================
5 * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
6 * Copyright © 2017 Amdocs
7 * ================================================================================
8 * Licensed under the Apache License, Version 2.0 (the "License");
9 * you may not use this file except in compliance with the License.
10 * You may obtain a copy of the License at
12 * http://www.apache.org/licenses/LICENSE-2.0
14 * Unless required by applicable law or agreed to in writing, software
15 * distributed under the License is distributed on an "AS IS" BASIS,
16 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17 * See the License for the specific language governing permissions and
18 * limitations under the License.
19 * ============LICENSE_END=========================================================
21 * ECOMP is a trademark and service mark of AT&T Intellectual Property.
23 package org.onap.aai.restclient.client;
25 import java.io.ByteArrayOutputStream;
26 import java.text.SimpleDateFormat;
27 import java.util.Arrays;
28 import java.util.List;
30 import java.util.Map.Entry;
31 import java.util.UUID;
32 import java.util.concurrent.ConcurrentHashMap;
33 import java.util.concurrent.ConcurrentMap;
35 import javax.ws.rs.core.MediaType;
36 import javax.ws.rs.core.MultivaluedMap;
37 import javax.ws.rs.core.Response;
39 import org.onap.aai.restclient.enums.RestAuthenticationMode;
40 import org.onap.aai.restclient.logging.RestClientMsgs;
41 import org.onap.aai.restclient.rest.RestClientBuilder;
42 import org.onap.aai.cl.api.LogFields;
43 import org.onap.aai.cl.api.LogLine;
44 import org.onap.aai.cl.api.Logger;
45 import org.onap.aai.cl.eelf.LoggerFactory;
46 import org.onap.aai.cl.mdc.MdcContext;
47 import org.onap.aai.cl.mdc.MdcOverride;
49 import com.sun.jersey.api.client.Client;
50 import com.sun.jersey.api.client.ClientResponse;
51 import com.sun.jersey.api.client.WebResource;
52 import com.sun.jersey.api.client.WebResource.Builder;
53 import com.sun.jersey.core.util.MultivaluedMapImpl;
57 * This class provides a general client implementation that micro services can use for communicating
58 * with the endpoints via their exposed REST interfaces.
62 public class RestClient {
65 * This is a generic builder that is used for constructing the REST client that we will use to
66 * communicate with the REST endpoint.
68 private RestClientBuilder clientBuilder;
70 private final ConcurrentMap<String,InitializedClient> CLIENT_CACHE = new ConcurrentHashMap<>();
71 private static final String REST_CLIENT_INSTANCE = "REST_CLIENT_INSTANCE";
73 /** Standard logger for producing log statements. */
74 private Logger logger = LoggerFactory.getInstance().getLogger("AAIRESTClient");
76 /** Standard logger for producing metric statements. */
77 private Logger metricsLogger = LoggerFactory.getInstance().getMetricsLogger("AAIRESTClient");
79 private SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSXXX");
81 /** Reusable function call for GET REST operations. */
82 private final RestOperation getOp = new GetRestOperation();
84 /** Reusable function call for PUT REST operations. */
85 private final RestOperation putOp = new PutRestOperation();
87 /** Reusable function call for POST REST operations. */
88 private final RestOperation postOp = new PostRestOperation();
90 /** Reusable function call for DELETE REST operations. */
91 private final RestOperation deleteOp = new DeleteRestOperation();
93 /** Reusable function call for HEAD REST operations. */
94 private final RestOperation headOp = new HeadRestOperation();
96 /** Reusable function call for PATCH REST operations. */
97 private final RestOperation patchOp = new PatchRestOperation();
101 * Creates a new instance of the {@link RestClient}.
103 public RestClient() {
105 clientBuilder = new RestClientBuilder();
111 * Creates a new instance of the {@link RestClient} using the supplied {@link RestClientBuilder}.
113 * @param rcBuilder - The REST client builder that this instance of the {@link RestClient} should
116 public RestClient(RestClientBuilder rcBuilder) {
117 clientBuilder = rcBuilder;
120 public RestClient authenticationMode(RestAuthenticationMode mode) {
121 logger.debug("Set rest authentication mode= " + mode);
122 clientBuilder.setAuthenticationMode(mode);
126 public RestClient basicAuthUsername(String username) {
127 logger.debug("Set SSL BasicAuth username = " + username);
128 clientBuilder.setBasicAuthUsername(username);
132 public RestClient basicAuthPassword(String password) {
134 * purposely not logging out the password, I guess we could obfuscate it if we really want to
137 clientBuilder.setBasicAuthPassword(password);
143 * Sets the flag to indicate whether or not validation should be performed against the host name
144 * of the server we are trying to communicate with.
146 * @parameter validate - Set to true to enable validation, false to disable
148 * @return The AAIRESTClient instance. This is useful for chaining parameter assignments.
150 public RestClient validateServerHostname(boolean validate) {
151 logger.debug("Set validate server hostname = " + validate);
152 clientBuilder.setValidateServerHostname(validate);
158 * Sets the flag to indicate whether or not validation should be performed against the certificate
161 * @parameter validate - Set to true to enable validation, false to disable.
163 * @return The AAIRESTClient instance. This is useful for chaining parameter assignments.
165 public RestClient validateServerCertChain(boolean validate) {
166 logger.debug("Set validate server certificate chain = " + validate);
167 clientBuilder.setValidateServerCertChain(validate);
173 * Assigns the client certificate file to use.
175 * @param filename - The name of the certificate file.
177 * @return The AAIRESTClient instance. This is useful for chaining parameter assignments.
179 public RestClient clientCertFile(String filename) {
180 logger.debug("Set client certificate filename = " + filename);
181 clientBuilder.setClientCertFileName(filename);
187 * Assigns the client certificate password to use.
189 * @param password - The certificate password.
191 * @return The AAIRESTClient instance. This is useful for chaining parameter assignments.
193 public RestClient clientCertPassword(String password) {
194 clientBuilder.setClientCertPassword(password);
200 * Assigns the name of the trust store file to use.
202 * @param filename - the name of the trust store file.
204 * @return The AAIRESTClient instance. This is useful for chaining parameter assignments.
206 public RestClient trustStore(String filename) {
207 logger.debug("Set trust store filename = " + filename);
208 clientBuilder.setTruststoreFilename(filename);
214 * Assigns the connection timeout (in ms) to use when connecting to the target server.
216 * @param timeout - The length of time to wait in ms before timing out.
218 * @return The AAIRESTClient instance. This is useful for chaining parameter assignments.
220 public RestClient connectTimeoutMs(int timeout) {
221 logger.debug("Set connection timeout = " + timeout + " ms");
222 clientBuilder.setConnectTimeoutInMs(timeout);
228 * Assigns the read timeout (in ms) to use when communicating with the target server.
230 * @param timeout The read timeout in milliseconds.
232 * @return The AAIRESTClient instance. This is useful for chaining parameter assignments.
234 public RestClient readTimeoutMs(int timeout) {
235 logger.debug("Set read timeout = " + timeout + " ms");
236 clientBuilder.setReadTimeoutInMs(timeout);
241 * Configures the client for a specific SSL protocol
243 * @param sslProtocol - protocol string constant such as TLS, TLSv1, TLSv1.1, TLSv1.2
245 * @return The AAIRESTClient instance.
247 public RestClient sslProtocol(String sslProtocol) {
248 logger.debug("Set sslProtocol = " + sslProtocol);
249 clientBuilder.setSslProtocol(sslProtocol);
253 private boolean shouldRetry(OperationResult operationResult) {
255 if (operationResult == null) {
259 int resultCode = operationResult.getResultCode();
261 if (resultCode == 200) {
265 if (resultCode == 404) {
274 * This method operates on a REST endpoint by submitting an HTTP operation request against the
276 * This variant of the method will perform a requested number of retries in the event that the
277 * first request is unsuccessful.
279 * @param operation - the REST operation type to send to the url
280 * @param url - The REST endpoint to submit the REST request to.
281 * @param payload - They payload to provide in the REST request, if applicable
282 * @param headers - The headers that should be passed in the request
283 * @param contentType - The content type of the payload
284 * @param responseType - The expected format of the response.
286 * @return The result of the REST request.
288 protected OperationResult processRequest(RestOperation operation, String url, String payload,
289 Map<String, List<String>> headers, MediaType contentType, MediaType responseType,
293 OperationResult result = null;
295 long startTimeInMs = System.currentTimeMillis();
296 for (int retryCount = 0; retryCount < numRetries; retryCount++) {
298 logger.info(RestClientMsgs.HTTP_REQUEST_WITH_RETRIES, operation.getRequestType().toString(),
299 url, Integer.toString(retryCount + 1));
301 // Submit our query to the AAI.
302 result = processRequest(operation, url, payload, headers, contentType, responseType);
304 // If the submission was successful then we're done.
306 if (!shouldRetry(result)) {
308 logger.info(RestClientMsgs.HTTP_REQUEST_TIME_WITH_RETRIES, operation.getRequestType().toString(),url,
309 Long.toString(System.currentTimeMillis() - startTimeInMs),
310 Integer.toString(retryCount));
312 result.setNumRetries(retryCount);
317 // Our submission was unsuccessful...
319 // Sleep between re-tries to be nice to the target system.
322 } catch (InterruptedException e) {
323 logger.error(RestClientMsgs.HTTP_REQUEST_INTERRUPTED, url, e.getLocalizedMessage());
328 // If we've gotten this far, then we failed all of our retries.
329 if (result == null) {
330 result = new OperationResult();
333 result.setNumRetries(numRetries);
334 result.setResultCode(504);
335 result.setFailureCause("Failed to get a successful result after multiple retries to target server.");
342 * This method operates on a REST endpoint by submitting an HTTP operation request against the
345 * @param operation - the REST operation type to send to the url
346 * @param url - The REST endpoint to submit the REST request to.
347 * @param payload - They payload to provide in the REST request, if applicable
348 * @param headers - The headers that should be passed in the request
349 * @param contentType - The content type of the payload
350 * @param responseType - The expected format of the response.
352 * @return The result of the REST request.
354 protected OperationResult processRequest(RestOperation operation, String url, String payload,
355 Map<String, List<String>> headers, MediaType contentType, MediaType responseType) {
357 ClientResponse clientResponse = null;
358 OperationResult operationResult = new OperationResult();
359 ByteArrayOutputStream baos = new ByteArrayOutputStream();
361 String requestType = operation.getRequestType().name();
363 // Grab the current time so that we can log how long the
364 // query took once we are done.
365 long startTimeInMs = System.currentTimeMillis();
366 MdcOverride override = new MdcOverride();
367 override.addAttribute(MdcContext.MDC_START_TIME, formatter.format(startTimeInMs));
369 logger.info(RestClientMsgs.HTTP_REQUEST, requestType, url);
373 // Get a REST client instance for our request.
374 Client client = getClient();
376 // Debug log the request
377 debugRequest(url, payload, headers, responseType);
379 // Get a client request builder, and submit our GET request.
380 Builder builder = getClientBuilder(client, url, payload, headers, contentType, responseType);
381 clientResponse = operation.processOperation(builder);
383 populateOperationResult(clientResponse, operationResult);
385 // Debug log the response
386 debugResponse(operationResult, clientResponse.getHeaders());
388 } catch (Exception ex) {
390 logger.error(RestClientMsgs.HTTP_REQUEST_ERROR, requestType, url, ex.getLocalizedMessage());
391 operationResult.setResultCode(500);
392 operationResult.setFailureCause(
393 "Error during GET operation to AAI with message = " + ex.getLocalizedMessage());
397 if (logger.isDebugEnabled()) {
398 logger.debug(baos.toString());
401 // Not every valid response code is actually represented by the Response.Status
402 // object, so we need to guard against missing codes, otherwise we throw null
403 // pointer exceptions when we try to generate our metrics logs...
404 Response.Status responseStatus =
405 Response.Status.fromStatusCode(operationResult.getResultCode());
406 String responseStatusCodeString = "";
407 if (responseStatus != null) {
408 responseStatusCodeString = responseStatus.toString();
411 metricsLogger.info(RestClientMsgs.HTTP_REQUEST_TIME,
412 new LogFields().setField(LogLine.DefinedFields.STATUS_CODE, responseStatusCodeString)
413 .setField(LogLine.DefinedFields.RESPONSE_CODE, operationResult.getResultCode())
414 .setField(LogLine.DefinedFields.RESPONSE_DESCRIPTION, operationResult.getResult()),
415 override, requestType, Long.toString(System.currentTimeMillis() - startTimeInMs), url);
416 logger.info(RestClientMsgs.HTTP_REQUEST_TIME, requestType,
417 Long.toString(System.currentTimeMillis() - startTimeInMs), url);
418 logger.info(RestClientMsgs.HTTP_RESPONSE, url,
419 operationResult.getResultCode() + " " + responseStatusCodeString);
422 return operationResult;
426 * This method submits an HTTP PUT request against the supplied URL.
428 * @param url - The REST endpoint to submit the PUT request to.
429 * @param payload - the payload to send to the supplied URL
430 * @param headers - The headers that should be passed in the request
431 * @param contentType - The content type of the payload
432 * @param responseType - The expected format of the response.
434 * @return The result of the PUT request.
436 public OperationResult put(String url, String payload, Map<String, List<String>> headers,
437 MediaType contentType, MediaType responseType) {
438 return processRequest(putOp, url, payload, headers, contentType, responseType);
442 * This method submits an HTTP POST request against the supplied URL.
444 * @param url - The REST endpoint to submit the POST request to.
445 * @param payload - the payload to send to the supplied URL
446 * @param headers - The headers that should be passed in the request
447 * @param contentType - The content type of the payload
448 * @param responseType - The expected format of the response.
450 * @return The result of the POST request.
452 public OperationResult post(String url, String payload, Map<String, List<String>> headers,
453 MediaType contentType, MediaType responseType) {
454 return processRequest(postOp, url, payload, headers, contentType, responseType);
458 * This method submits an HTTP POST request against the supplied URL, and emulates a PATCH
459 * operation by setting a special header value
461 * @param url - The REST endpoint to submit the POST request to.
462 * @param payload - the payload to send to the supplied URL
463 * @param headers - The headers that should be passed in the request
464 * @param contentType - The content type of the payload
465 * @param responseType - The expected format of the response.
467 * @return The result of the POST request.
469 public OperationResult patch(String url, String payload, Map<String, List<String>> headers,
470 MediaType contentType, MediaType responseType) {
471 return processRequest(patchOp, url, payload, headers, contentType, responseType);
476 * This method submits an HTTP HEAD request against the supplied URL
478 * @param url - The REST endpoint to submit the POST request to.
479 * @param headers - The headers that should be passed in the request
480 * @param responseType - The expected format of the response.
482 * @return The result of the POST request.
484 public OperationResult head(String url, Map<String, List<String>> headers,
485 MediaType responseType) {
486 return processRequest(headOp, url, null, headers, null, responseType);
490 * This method submits an HTTP GET request against the supplied URL.
492 * @param url - The REST endpoint to submit the GET request to.
493 * @param headers - The headers that should be passed in the request
494 * @param responseType - The expected format of the response.
496 * @return The result of the GET request.
498 public OperationResult get(String url, Map<String, List<String>> headers,
499 MediaType responseType) {
500 return processRequest(getOp, url, null, headers, null, responseType);
504 * This method submits an HTTP GET request against the supplied URL.
505 * This variant of the method will perform a requested number of retries in the event that the
506 * first request is unsuccessful.
508 * @param url - The REST endpoint to submit the GET request to.
509 * @param headers - The headers that should be passed in the request
510 * @param responseType - The expected format of the response.
511 * @param numRetries - The number of times to try resubmitting the request in the event of a
514 * @return The result of the GET request.
516 public OperationResult get(String url, Map<String, List<String>> headers, MediaType responseType,
518 return processRequest(getOp, url, null, headers, null, responseType, numRetries);
522 * This method submits an HTTP DELETE request against the supplied URL.
524 * @param url - The REST endpoint to submit the DELETE request to.
525 * @param headers - The headers that should be passed in the request
526 * @param responseType - The expected format of the response.
528 * @return The result of the DELETE request.
530 public OperationResult delete(String url, Map<String, List<String>> headers,
531 MediaType responseType) {
532 return processRequest(deleteOp, url, null, headers, null, responseType);
536 * This method does a health check ("ping") against the supplied URL.
538 * @param url - The REST endpoint to attempt a health check.
539 * @param srcAppName - The name of the application using this client.
540 * @param destAppName - The name of the destination app.
542 * @return A boolean value. True if connection attempt was successful, false otherwise.
545 public boolean healthCheck(String url, String srcAppName, String destAppName) {
546 return healthCheck(url, srcAppName, destAppName, MediaType.TEXT_PLAIN_TYPE);
551 * This method does a health check ("ping") against the supplied URL.
553 * @param url - The REST endpoint to attempt a health check.
554 * @param srcAppName - The name of the application using this client.
555 * @param destAppName - The name of the destination app.
556 * @param responseType - The response type.
558 * @return A boolean value. True if connection attempt was successful, false otherwise.
561 public boolean healthCheck(String url, String srcAppName, String destAppName,
562 MediaType responseType) {
563 MultivaluedMap<String, String> headers = new MultivaluedMapImpl();
564 headers.put(Headers.FROM_APP_ID, Arrays.asList(new String[] {srcAppName}));
565 headers.put(Headers.TRANSACTION_ID, Arrays.asList(new String[] {UUID.randomUUID().toString()}));
568 logger.info(RestClientMsgs.HEALTH_CHECK_ATTEMPT, destAppName, url);
569 OperationResult result = get(url, headers, responseType);
571 if (result != null && result.getFailureCause() == null) {
572 logger.info(RestClientMsgs.HEALTH_CHECK_SUCCESS, destAppName, url);
575 logger.error(RestClientMsgs.HEALTH_CHECK_FAILURE, destAppName, url, result != null ? result.getFailureCause()
579 } catch (Exception e) {
580 logger.error(RestClientMsgs.HEALTH_CHECK_FAILURE, destAppName, url, e.getMessage());
586 * This method constructs a client request builder that can be used for submitting REST requests
587 * to the supplied URL endpoint.
589 * @param client - The REST client we will be using to talk to the server.
590 * @param url - The URL endpoint that our request will be submitted to.
591 * @param headers - The headers that should be passed in the request
592 * @param contentType - the content type of the payload
593 * @param responseType - The expected format of the response.
595 * @return A client request builder.
597 private Builder getClientBuilder(Client client, String url, String payload,
598 Map<String, List<String>> headers, MediaType contentType, MediaType responseType) {
600 WebResource resource = client.resource(url);
601 Builder builder = resource.accept(responseType);
603 if (contentType != null) {
604 builder.type(contentType);
607 if (payload != null) {
608 builder.entity(payload);
611 if (headers != null) {
612 for (Entry<String, List<String>> header : headers.entrySet()) {
613 builder.header(header.getKey(), String.join(";",header.getValue()));
616 if (clientBuilder.getAuthenticationMode() == RestAuthenticationMode.SSL_BASIC) {
617 builder = builder.header(Headers.AUTHORIZATION,
618 clientBuilder.getBasicAuthenticationCredentials());
626 private void debugRequest(String url, String payload, Map<String, List<String>> headers,
627 MediaType responseType) {
628 if (logger.isDebugEnabled()) {
629 StringBuilder debugRequest = new StringBuilder("REQUEST:\n");
630 debugRequest.append("URL: ").append(url).append("\n");
631 debugRequest.append("Payload: ").append(payload).append("\n");
632 debugRequest.append("Response Type: ").append(responseType).append("\n");
633 if (headers != null) {
634 debugRequest.append("Headers: ");
635 for (Entry<String, List<String>> header : headers.entrySet()) {
636 debugRequest.append("\n\t").append(header.getKey()).append(":");
637 for (String headerEntry : header.getValue()) {
638 debugRequest.append("\"").append(headerEntry).append("\" ");
642 logger.debug(debugRequest.toString());
646 private void debugResponse(OperationResult operationResult,
647 MultivaluedMap<String, String> headers) {
648 if (logger.isDebugEnabled()) {
649 StringBuilder debugResponse = new StringBuilder("RESPONSE:\n");
650 debugResponse.append("Result: ").append(operationResult.getResultCode()).append("\n");
651 debugResponse.append("Failure Cause: ").append(operationResult.getFailureCause())
653 debugResponse.append("Payload: ").append(operationResult.getResult()).append("\n");
654 if (headers != null) {
655 debugResponse.append("Headers: ");
656 for (Entry<String, List<String>> header : headers.entrySet()) {
657 debugResponse.append("\n\t").append(header.getKey()).append(":");
658 for (String headerEntry : header.getValue()) {
659 debugResponse.append("\"").append(headerEntry).append("\" ");
663 logger.debug(debugResponse.toString());
668 * This method creates an instance of the low level REST client to use for communicating with the
669 * AAI, if one has not already been created, otherwise it returns the already created instance.
671 * @return A {@link Client} instance.
673 protected Client getClient() throws Exception {
676 * Attempting a new way of doing non-blocking thread-safe lazy-initialization by using Java 1.8
677 * computeIfAbsent functionality. A null value will not be stored, but once a valid mapping has
678 * been established, then the same value will be returned.
680 * One awkwardness of the computeIfAbsent is the lack of support for thrown exceptions, which
681 * required a bit of hoop jumping to preserve the original exception for the purpose of
682 * maintaining the pre-existing this API signature.
685 final InitializedClient clientInstance =
686 CLIENT_CACHE.computeIfAbsent(REST_CLIENT_INSTANCE, k -> loggedClientInitialization());
688 if (clientInstance.getCaughtException() != null) {
689 throw new InstantiationException(clientInstance.getCaughtException().getMessage());
692 return clientInstance.getClient();
697 * This method will only be called if computerIfAbsent is true. The return value is null, then the result is not
700 * @return a new client instance or null
702 private InitializedClient loggedClientInitialization() {
704 if (logger.isDebugEnabled()) {
705 logger.debug("Instantiating REST client with following parameters:");
706 logger.debug(clientBuilder.toString());
709 InitializedClient initClient = new InitializedClient();
712 initClient.setClient(clientBuilder.getClient());
713 } catch ( Throwable error ) {
714 initClient.setCaughtException(error);
723 * This method populates the fields of an {@link OperationResult} instance based on the contents
724 * of a {@link ClientResponse} received in response to a REST request.
726 private void populateOperationResult(ClientResponse response, OperationResult opResult) {
728 // If we got back a NULL response, then just produce a generic
729 // error code and result indicating this.
730 if (response == null) {
731 opResult.setResultCode(500);
732 opResult.setFailureCause("Client response was null");
736 int statusCode = response.getStatus();
737 opResult.setResultCode(statusCode);
739 if (opResult.wasSuccessful()) {
740 if (statusCode != Response.Status.NO_CONTENT.getStatusCode()) {
741 opResult.setResult(response.getEntity(String.class));
744 opResult.setFailureCause(response.getEntity(String.class));
747 opResult.setHeaders(response.getHeaders());
750 private class GetRestOperation implements RestOperation {
751 public ClientResponse processOperation(Builder builder) {
752 return builder.get(ClientResponse.class);
755 public RequestType getRequestType() {
756 return RequestType.GET;
760 private class PutRestOperation implements RestOperation {
761 public ClientResponse processOperation(Builder builder) {
762 return builder.put(ClientResponse.class);
765 public RequestType getRequestType() {
766 return RequestType.PUT;
770 private class PostRestOperation implements RestOperation {
771 public ClientResponse processOperation(Builder builder) {
772 return builder.post(ClientResponse.class);
775 public RequestType getRequestType() {
776 return RequestType.POST;
780 private class DeleteRestOperation implements RestOperation {
781 public ClientResponse processOperation(Builder builder) {
782 return builder.delete(ClientResponse.class);
785 public RequestType getRequestType() {
786 return RequestType.DELETE;
790 private class HeadRestOperation implements RestOperation {
791 public ClientResponse processOperation(Builder builder) {
792 return builder.head();
795 public RequestType getRequestType() {
796 return RequestType.HEAD;
800 private class PatchRestOperation implements RestOperation {
803 * Technically there is no standarized PATCH operation for the
804 * jersey client, but we can use the method-override approach
807 public ClientResponse processOperation(Builder builder) {
808 builder = builder.header("X-HTTP-Method-Override", "PATCH");
809 return builder.post(ClientResponse.class);
812 public RequestType getRequestType() {
813 return RequestType.PATCH;
819 * Interface used wrap a Jersey REST call using a functional interface.
821 private interface RestOperation {
824 * Method used to wrap the functionality of making a REST call out to the endpoint.
826 * @param builder the Jersey builder used to make the request
827 * @return the response from the REST endpoint
829 public ClientResponse processOperation(Builder builder);
832 * Returns the REST request type.
834 public RequestType getRequestType();
837 * The supported REST request types.
839 public enum RequestType {
840 GET, PUT, POST, DELETE, PATCH, HEAD
845 * An entity to encapsulate an expected result and a potential failure cause when returning from a
846 * functional interface during the computeIfAbsent call.
848 private class InitializedClient {
849 private Client client;
850 private Throwable caughtException;
852 public InitializedClient() {
854 caughtException = null;
857 public Client getClient() {
860 public void setClient(Client client) {
861 this.client = client;
863 public Throwable getCaughtException() {
864 return caughtException;
866 public void setCaughtException(Throwable caughtException) {
867 this.caughtException = caughtException;