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Encountering this error while running test cases -ERROR N/A (Null Pointer Exception)

#Test
public void testBatchFailClientBatchSyncCallIllegalArgumentExceptions() throws Exception {
Map<String, String> singletonMap = Collections.singletonMap(ACCEPT_STRING_ID, defaultLocalizationMap.get(ACCEPT_STRING_ID));
StringRequest[] requests = stringRequestFactory.createRequests(singletonMap);
when(lmsClient.batchSyncCall(requests)).thenThrow(new IllegalArgumentException());
List<Backend.Response> responses = callLms(new StringRequest[] {requests[0]});
Assert.assertNotNull(responses);
assertEquals(EntityDescriptors.ERROR_V1, responses.get(0).entityDescriptor());
assertEquals(Http.Status.SERVICE_UNAVAILABLE, responses.get(0).status());
}
#Test
public void testBatchFailClientBatchSyncCallIOException() throws Exception {
Map<String, String> singletonMap = Collections.singletonMap(ACCEPT_STRING_ID, defaultLocalizationMap.get(ACCEPT_STRING_ID));
StringRequest[] requests = stringRequestFactory.createRequests(singletonMap);
when(lmsClient.batchSyncCall(requests)).thenThrow(new IOException());
List<Backend.Response> responses = callLms(new StringRequest[] {requests[0]});
Assert.assertNotNull(responses);
assertEquals(EntityDescriptors.ERROR_V1, responses.get(0).entityDescriptor());
assertEquals(Http.Status.SERVICE_UNAVAILABLE, responses.get(0).status());
}
Source Code -
#Override
public List<Backend.Response> handleRequests(BackendRequestContext context, List<Backend.Request> requests, Metrics metrics) {
StringRequest[] stringRequests = new StringRequest[requests.size()];
final String language = context.locale().toLanguageTag().replace("-", "_");
for (int i = 0; i < requests.size(); i++) {
final Backend.Request request = requests.get(i);
final String id = request.requiredPathParam(STRING_ID_PATH_PARAM);
final Optional<String> marketplaceDisplayName = request.queryParam(MARKETPLACE_NAME_QUERY_PARAM);
final Optional<String> stage = request.queryParam(STAGE_QUERY_PARAM);
final StringRequest stringRequest = new StringRequest(id);
stringRequest.setLanguage(language);
marketplaceDisplayName.ifPresent(stringRequest::setMarketplaceName);
stage.map(Stage::getStage).ifPresent(stringRequest::setStage);
stringRequests[i] = stringRequest;
}
StringResultBatch batchResult = invokeBatchSync(stringRequests);
return IntStream.of(requests.size()).mapToObj(i -> {
final Backend.Request request = requests.get(i);
try {
return transform(request, batchResult.get(i), language);
} catch (IOException e) {
LOGGER.error("", e);
return Backend.Response.builder()
.withRequest(request)
.withEntityDescriptor(EntityDescriptors.ERROR_V1)
.withStatus(Http.Status.SERVICE_UNAVAILABLE)
.withBody(ErrorResponses.ServerError.serviceUnavailable(ErrorResponse.InternalInfo.builder()
.withMessage("Error retrieving ["
+ request.requiredPathParam(STRING_ID_PATH_PARAM)
+ "]")
.build())
.tokens())
.build();
}
}
).collect(Collectors.toList());
}
private StringResultBatch invokeBatchSync(StringRequest[] stringRequests) {
try {
// LMS Client has an async batch call,
// but it returns a proprietary class (StringResultBatchFuture) which eventually wraps a BSFFutureReply.
// Neither of which provide access to anything like a Java-standard Future.
return client.batchSyncCall(stringRequests);
} catch (IllegalArgumentException | IOException e) {
//
return null;
}
}
I have two test cases here for the source file. I'm getting the Error N/A. It says null pointer exception. Can someone please review this and help me with this. It will be really appreciated. Thank you in advance
P.S - The source file takes input request as string and performs string translation and returns us that string.

WebClient Spring Boot : Data is saved only if it returns value

I am using Mailchimp api when I return value it works fine but when I don't return any value it does not work and also not throwing any exception.
#GetMapping(value = "/members/add/{email}") //using GET to test
public Mono<String> addMember(#PathVariable String email) {
User user = new User();
user.setFirst_name("Test");
user.setLast_name("Data");
user.setEmail_id(email);
return mailchimpService.create(user);
}
This is not saving data
#GetMapping(value = "/members/add/{email}") //using GET to test
public Mono<String> addMember(#PathVariable String email) {
User user = new User();
user.setFirst_name("Test");
user.setLast_name("Data");
user.setPhone("");
user.setEmail_id(email);
mailchimpService.create(user);
return null;
}
public Mono<String> create(User user) {
try {
Members members = convertUserToMailchimpObject(user);
return webClient.post()
.contentType(MediaType.APPLICATION_JSON)
.body(BodyInserters.fromValue(members))
.exchangeToMono(clientResponse -> {
if (clientResponse.statusCode().is5xxServerError()) {
clientResponse.body((clientHttpResponse, context) -> clientHttpResponse.getBody());
System.out.println(clientResponse.statusCode() + " statusCode error");
System.out.println(clientResponse.statusCode().value() + " value error");
return clientResponse.bodyToMono(String.class);
} else
System.out.println(clientResponse.statusCode() + " statusCode");
System.out.println(clientResponse.statusCode().value() + " value");
return clientResponse.bodyToMono(String.class);
});
} catch (Exception e) {
e.printStackTrace();
return null;
}
}

The reason is that in reactive programming nothing happens until you subscribe. The create method is never get subscribed thus the webclient call is never made.
The first snippet works because the Webflux framework will subscribe for you as long as you provide your publisher(a Mono).

Spring RestTemplate exchange throws UnhandledHttpStatusException

Overview:
I am going to use RestTemplate to invoke a get request from external REST webservice.
My code is as follows:
#Slf4j
#Component("AccMemberDetailsApiControllerImpl")
public class AccMemberDetailsApiControllerImpl implements MemberDetailsApiController {
private static final String CONTENT_TYPE_HEADER_NAME = "Content-Type";
private static final String AUTHORIZATION_HEADER_NAME = "Authorization";
private static final String USERID_PARAMETER_NAME = "userId";
private static final String VEHICLEID_PARAMETER_NAME = "vehicleId";
private static final ObjectMapper mapper = new ObjectMapper();
/**
* This constant is used to check whether or not the response from ACC is an empty JSON string
*/
private static final String EMPTY_RESPONSE = "{}";
#Value("${com.blss.memberServices.provider.posServiceURL}")
private String accPosServiceURL;
#Autowired
private RestTemplate restTemplate;
#Autowired
private AccTokenUtility accTokenUtility;
#Autowired
private ResourceMessage resourceMessage;
void setAccTokenUtility(AccTokenUtility accTokenUtility) {
this.accTokenUtility = accTokenUtility;
}
void setResourceMessage(ResourceMessage resourceMessage) {
this.resourceMessage = resourceMessage;
}
/**
* #see MemberDetailsApiController#getMemberDetails(String, String)
*/
#Override
public MemberDetailsModel getMemberDetails(String storeId, String membershipIdentifier) {
/**
* Getting CAD token
*/
String token = accTokenUtility.getCadToken();
/**
* Preparing the request
*/
HttpHeaders headers = new HttpHeaders();
// headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
headers.set(CONTENT_TYPE_HEADER_NAME, MediaType.APPLICATION_JSON_VALUE);
headers.set(AUTHORIZATION_HEADER_NAME, token);
HttpEntity<String> entity = new HttpEntity<>(headers);
/**
* Creating the dispatch URL by means of userId and vehicleId
*/
String dispatchURL = accPosServiceURL + "DispatchedEvent/{userId}/{vehicleId}";
/**
* Creating the URL variables and being valued by corresponding method parameters
*/
Map<String, String> parameters = new HashMap<>();
// parameters.put(USERID_PARAMETER_NAME, storeId);
parameters.put(USERID_PARAMETER_NAME, "mr2");
// parameters.put(VEHICLEID_PARAMETER_NAME, membershipIdentifier);
parameters.put(VEHICLEID_PARAMETER_NAME, "VEH1");
/**
* Calling the rest webservice and returning response with body of type {#link AccMemberDetails}
*/
ResponseEntity<String> response;
MemberDetailsModel memberDetailsModel = null;
AccMemberDetails accMemberDetails;
try {
response = restTemplate.exchange(dispatchURL, HttpMethod.GET, entity, String.class, parameters);
if (response == null || StringUtils.isBlank(response.getBody()) || EMPTY_RESPONSE.equals(response.getBody())) {
throw new ResourceNotFoundException(resourceMessage.getMessage(MEMBER_ERROR_NOT_FOUND, storeId, membershipIdentifier));
} else {
accMemberDetails = deserialize(response.getBody(), AccMemberDetails.class);
String accErrorMessage = accMemberDetails.getUserMessage();
if (!StringUtils.isBlank(accErrorMessage)) {
throw new InternalServerException(resourceMessage.getMessage(MEMBER_ERROR_MESSAGE_FROM_API, "ACC", accErrorMessage));
}
memberDetailsModel = convert(accMemberDetails);
}
} catch (RestClientException e) {
handleExceptions(e, storeId, membershipIdentifier);
}
return memberDetailsModel;
}
/**
* This method is responsible for deserializing string REST response into an object of type {#link AccMemberDetails}
*/
<T> T deserialize(final String response, final Class<T> responseClass) {
try {
return mapper.readValue(response, responseClass);
} catch (IOException e) {
throw new InternalServerException(resourceMessage.getMessage(MEMBER_ERROR_MAP_RESPONSE_OBJECT), e);
}
}
/**
* This method is responsible for converting an instance of type {#link AccMemberDetails} to an instance of type
* {#link MemberDetailsModel}
*
* #param accMemberDetails an instance of type {#link AccMemberDetails}
* #return an instance of type {#link MemberDetailsModel}
*/
MemberDetailsModel convert(AccMemberDetails accMemberDetails) {
MemberDetailsModel memberDetailsModel = new MemberDetailsModel();
memberDetailsModel.setEventId(accMemberDetails.getEventId());
memberDetailsModel.setMemberName(accMemberDetails.getMemberName());
memberDetailsModel.setMembershipNumber(accMemberDetails.getMembershipNumber());
memberDetailsModel.setMembershipLevel(accMemberDetails.getPricingLevel());
return memberDetailsModel;
}
/**
* This method is responsible for handling Exceptions may be thrown by ACC REST webservice
*
* #param e an instance of type {#link RestClientException}
* #param storeId an instance of type {#link String} and used in building exception messages
* #param membershipIdentifier an instance of type {#link String} and used in building exception messages
*/
private void handleExceptions(RestClientException e, String storeId, String membershipIdentifier) {
if (e instanceof HttpStatusCodeException) {
HttpStatusCodeException httpStatusCodeException = (HttpStatusCodeException) e;
HttpStatus httpStatusCode = httpStatusCodeException.getStatusCode();
if (404 == httpStatusCode.value()) {
throw new ResourceNotFoundException(resourceMessage.getMessage(MEMBER_ERROR_NOT_FOUND, storeId, membershipIdentifier), e);
} else if (500 == httpStatusCode.value()) {
throw new InternalServerException(resourceMessage.getMessage(MEMBER_SERVER_ERROR, "ACC"), e);
} else {
throw new InternalServerException(resourceMessage.getMessage(MEMBER_HTTP_STATUS_CODE_ERROR, "HttpStatusCodeException", "ACC"), e);
}
} else {
throw new InternalServerException(resourceMessage.getMessage(MEMBER_REST_CLIENT_ERROR, "RestClientException", "ACC"), e);
}
}
Problem
However I got UnhandledHttpStatusException after calling "restTemplate.exchange(dispatchURL, HttpMethod.GET, entity, String.class, parameters);" in the code snippet. the exception stack trace is as follows:
Caused by: org.springframework.web.client.UnknownHttpStatusCodeException: Unknown status code [443] null
at org.springframework.web.client.DefaultResponseErrorHandler.getHttpStatusCode(DefaultResponseErrorHandler.java:60)
at org.springframework.web.client.DefaultResponseErrorHandler.hasError(DefaultResponseErrorHandler.java:50)
at org.springframework.web.client.RestTemplate.handleResponse(RestTemplate.java:629)
at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:597)
at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:565)
at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:484)
at com.blss.retailServices.memberServices.controllers.impl.acc.AccMemberDetailsApiControllerImpl.getMemberDetails(AccMemberDetailsApiControllerImpl.java:110)
Now I would be grateful if anyone could suggest me a solution.

I called this webservice with curl by using "-v" in order to get more info in response. As a result, I got the same exception (443) from their side. So, It sounds like they should have a better exception handler to return meaningful exception messages.

ElasticSearch index exists not working / reliable

I am writing a simple Java wrapper around ElasticSearch's admin client. To test it I have a main method that first checks if an index exists (IndicesExistsRequest), if so deletes it (DeleteIndexRequest), and creates the index again. See code below. Yet I consistently get an IndexAlreadyExistsException.
By the way I am trying to get a client for the node that you start from the command prompt (by simply typing "elastic search"). I have tried every combination of methods on nodeBuilder's fluent interface, but I can't seem to get one.
public static void main(String[] args) {
ElasticSearchJavaClient esjc = new ElasticSearchJavaClient("nda");
if (esjc.indexExists()) {
esjc.deleteIndex();
}
esjc.createIndex();
URL url = SchemaCreator.class.getResource("/elasticsearch/specimen.type.json");
String mappings = FileUtil.getContents(url);
esjc.createType("specimen", mappings);
}
final Client esClient;
final IndicesAdminClient adminClient;
final String indexName;
public ElasticSearchJavaClient(String indexName) {
this.indexName = indexName;
esClient = nodeBuilder().clusterName("elasticsearch").client(true).node().client();
adminClient = esClient.admin().indices();
}
public boolean deleteIndex() {
logger.info("Deleting index " + indexName);
DeleteIndexRequest request = new DeleteIndexRequest(indexName);
try {
DeleteIndexResponse response = adminClient.delete(request).actionGet();
if (!response.isAcknowledged()) {
throw new Exception("Failed to delete index " + indexName);
}
logger.info("Index deleted");
return true;
} catch (IndexMissingException e) {
logger.info("No such index: " + indexName);
return false;
}
}
public boolean indexExists() {
logger.info(String.format("Verifying existence of index \"%s\"", indexName));
IndicesExistsRequest request = new IndicesExistsRequest(indexName);
IndicesExistsResponse response = adminClient.exists(request).actionGet();
if (response.isExists()) {
logger.info("Index exists");
return true;
}
logger.info("No such index");
return false;
}
public void createIndex() {
logger.info("Creating index " + indexName);
CreateIndexRequest request = new CreateIndexRequest(indexName);
IndicesAdminClient iac = esClient.admin().indices();
CreateIndexResponse response = iac.create(request).actionGet();
if (!response.isAcknowledged()) {
throw new Exception("Failed to create index " + indexName);
}
logger.info("Index created");
}

You can also execute a synchronous request like this:
boolean exists = client.admin().indices()
.prepareExists(INDEX_NAME)
.execute().actionGet().isExists();

Here is my solution when using RestHighLevelClient client;
Here a code-snippet: :
public boolean checkIfIndexExists(String indexName) throws IOException {
Response response = client.getLowLevelClient().performRequest("HEAD", "/" + indexName);
int statusCode = response.getStatusLine().getStatusCode();
return (statusCode != 404);
}
A contribution for someone else !

The skgemini's answer is ok if you want to check if index is available by the actual index name or any of its aliases.
If you however want to check only by the index name, here is how.
public boolean checkIfIndexExists(String index) {
IndexMetaData indexMetaData = client.admin().cluster()
.state(Requests.clusterStateRequest())
.actionGet()
.getState()
.getMetaData()
.index(index);
return (indexMetaData != null);
}

OK, I figured out a solution. Since the java client's calls are done asynchronously you have to use the variant which takes an action listener. The solution still gets a bit contrived though:
// Inner class because it's just used to be thrown out of
// the action listener implementation to signal that the
// index exists
private class ExistsException extends RuntimeException {
}
public boolean exists() {
logger.info(String.format("Verifying existence of index \"%s\"", indexName));
IndicesExistsRequest request = new IndicesExistsRequest(indexName);
try {
adminClient.exists(request, new ActionListener<IndicesExistsResponse>() {
public void onResponse(IndicesExistsResponse response) {
if (response.isExists()) {
throw new ExistsException();
}
}
public void onFailure(Throwable e) {
ExceptionUtil.smash(e);
}
});
}
catch (ExistsException e) {
return true;
}
return false;
}

I had the same issue but i didn't like the solution which uses an ActionListener. ElasticSearch also offers a Future variant (at least at version 6.1.0).
Here a code-snippet:
public boolean doesIndexExists(String indexName, TransportClient client) {
IndicesExistsRequest request = new IndicesExistsRequest(indexName);
ActionFuture<IndicesExistsResponse> future = client.admin().indices().exists(request);
try {
IndicesExistsResponse response = future.get();
boolean result = response.isExists();
logger.info("Existence of index '" + indexName + "' result is " + result);
return result;
} catch (InterruptedException | ExecutionException e) {
logger.error("Exception at waiting for IndicesExistsResponse", e);
return false;//do some clever exception handling
}
}
May be this helps someone else too. Cheers!

This works on Elasticsearch 7.x:
public boolean indexExists(String indexName) throws IOException {
return client.indices().exists(new org.elasticsearch.client.indices.GetIndexRequest(indexName), RequestOptions.DEFAULT);
}

Exception when saving a result

I am developping J2EE application with appfuse , i have a webform called easyVolAction that contain a method search() I need to save the result of search method in database but and an excpetion is generated when clicking in the action search :NullPointerException in object trajet .I created TrajetDaoHibernate:
public TrajetDaoHibernate() {
super(TrajetModel.class);
}
/**
* {#inheritDoc}
*/
#SuppressWarnings("unchecked")
public List<TrajetModel> getTrajet() {
Session session = getSessionFactory().getCurrentSession();
Query qry = session.createQuery("from TrajetModel u order by upper(u.id)");
return qry.list();
}
/**
* {#inheritDoc}
*/
public TrajetModel saveTrajet(TrajetModel trajet) {
if (log.isDebugEnabled()) {
log.debug("user's id: " + trajet.getId());
}
Session session = getSessionFactory().getCurrentSession();
session.saveOrUpdate(trajet);
// necessary to throw a DataIntegrityViolation and catch it in UserManager
session.flush();
return trajet;
}
#Override
public TrajetModel save(TrajetModel trajet) {
return this.saveTrajet(trajet);
}
and TrajetDao:
public interface TrajetDao extends GenericDao {
List<TrajetModel> getTrajet();
TrajetModel saveTrajet(TrajetModel trajet);
}
and trajetManager:
#Service("trajetManager")
public class TrajetModelImpl extends GenericManagerImpl<TrajetModel, Long> implements TrajetManager {
private TrajetDao trajetDao;
#Autowired
public void setTrajetModelDao(TrajetDao trajetDao) {
this.dao = trajetDao;
this.trajetDao = trajetDao;
}
/**
* {#inheritDoc}
*/
public TrajetModel getTrajet(String trajetId) {
return trajetDao.get(new Long(trajetId));
}
/**
* {#inheritDoc}
*/
public List<TrajetModel> getTrajet() {
return trajetDao.getAllDistinct();
}
/**
* {#inheritDoc}
*/
public TrajetModel saveTrajet(TrajetModel trajet) throws TrajetExistsException {
try {
return trajetDao.saveTrajet(trajet);
} catch (DataIntegrityViolationException e) {
//e.printStackTrace();
log.warn(e.getMessage());
throw new TrajetExistsException("Trajet '" + trajet.getNom() + "' already exists!");
} catch (JpaSystemException e) { // needed for JPA
//e.printStackTrace();
log.warn(e.getMessage());
throw new TrajetExistsException("Trajet '" + trajet.getNom() + "' already exists!");
}
}
}
finnaly the action where i declare the search method:
public String recherche() throws IOException, TrajetExistsException {
HttpServletRequest request = (HttpServletRequest) FacesContext
.getCurrentInstance().getExternalContext().getRequest();
// String url1 =
// FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap().get("hidden");
String departAller = request.getParameter("easyVolRobot:villeDepart");
String arriveeAller = request.getParameter("easyVolRobot:villeArrivee");
String jourAller = request.getParameter("easyVolRobot:jourDep");
String moisAller = request.getParameter("easyVolRobot:dateDep");
String jourRetour = request.getParameter("easyVolRobot:jourDep");
String moisRetour = request.getParameter("easyVolRobot:dateArr");
String jourAllerPlus1 = jourAller + 1;
parametre = "departAller=" + departAller + "&arriveeAller="
+ arriveeAller + "&jourAller=" + jourAller + "&moisAller="
+ moisAller + "&jourRetour=" + jourRetour + "&moisRetour="
+ moisRetour;
parametre1 = "departAller=" + departAller + "&arriveeAller="
+ arriveeAller + "&jourAller=" + jourAllerPlus1 + "&moisAller="
+ moisAller + "&jourRetour=" + jourRetour + "&moisRetour="
+ moisRetour;
String response = sendGetRequest(url, parametre);
// insert();
PrintStream out = null;
try {
out = new PrintStream(new FileOutputStream(
"/data/crawl/root/siteSNCF.html"));
out.print(response);
} finally {
if (out != null)
out.close();
}
// tableau de resultats des trajets
List<TrajetModel> listTrajets = new ArrayList<TrajetModel>();
// trajet
//TrajetModel trajet = new TrajetModel();
File input = new File("/data/crawl/root/siteSNCF.html");
Document doc = Jsoup.parse(input, "UTF-8",
"http://www.easyvols.org/france-voyage");
for (Element vol : doc.select("div.vols")) {
//trajet = new TrajetModel();
for (Element allerRetour : vol.select("div.aller-retour")) {
Elements aeroport = allerRetour.select("div.aeroport");
System.out.println(aeroport.text());
Elements depart = allerRetour.select("div.depart");
Elements arrive = allerRetour.select("div.arrivee");
Elements date = allerRetour.select("div.date");
trajet.setNom(aeroport.text());
trajet.setVilleDepart(depart.text());
trajet.setVilleArrive(arrive.text());
trajet.sethArrive(12);
trajet.sethDepart(11);
trajet.sethReqt(14);
}
Elements prix2 = vol.select("div.tarif");
trajet.setPrice(prix2.text());
trajet = trajetManager.saveTrajet(trajet);
System.out.println(trajet);}
return"mainMenu";
}

why you comment this line out?
//TrajetModel trajet = new TrajetModel();
I see no other line where you create the TrajetModel.
If that object is not initiated you get the NPE here:
trajet.setNom(aeroport.text());