resttemplate getForObject map responsetype - Printable Version +- 0Day Forums (https://zeroday.vip) +-- Forum: Coding (https://zeroday.vip/Forum-Coding) +--- Forum: FrameWork (https://zeroday.vip/Forum-FrameWork) +---- Forum: Spring (https://zeroday.vip/Forum-Spring) +---- Thread: resttemplate getForObject map responsetype (/Thread-resttemplate-getForObject-map-responsetype) |
resttemplate getForObject map responsetype - cyr670 - 08-02-2023 ***Update 02/05/2018 (about 4 years later)...I tested this again as people have been upvoting my question/answer and Sotirios Delimanolis is correct that I should not have to write the code in my answer to make this work. I used basically the same RestTemplate/REST service setup as shown in my question with the REST service having a confirmed response content type of application/json and RestTemplate was able to process the response with no issues into a Map.*** ---------- I'm invoking a rest service that returns `JSON` like this: { "some.key" : "some value", "another.key" : "another value" } I would like to think that I can invoke this service with a `java.util.Map` as the response type but that's not working for me. I get this exception: org.springframework.web.client.RestClientException: Could not extract response: no suitable HttpMessageConverter found for response type [interface java.util.Map] Should I just specify `String` as the response type and convert the `JSON` to a `Map`? <b>Edit I</b> Here's my restTemplate call: private Map<String, String> getBuildInfo(String buildUrl) { return restTemplate.getForObject(buildUrl, Map.class); } Here's how I'm setting up the restTemplate: @PostConstruct public void initialize() { List<ClientHttpRequestInterceptor> interceptors = new ArrayList<>(); interceptors.add(new ClientHttpRequestInterceptor() { @Override public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException { HttpRequestWrapper requestWrapper = new HttpRequestWrapper(request); requestWrapper.getHeaders().setAccept(Arrays.asList(MediaType.APPLICATION_JSON)); return execution.execute(requestWrapper, body); } }); restTemplate.setInterceptors(interceptors); } <b>Edit II</b> Full error message: org.springframework.web.client.RestClientException: Could not extract response: no suitable HttpMessageConverter found for response type [interface java.util.Map] and content type [application/octet-stream] at org.springframework.web.client.HttpMessageConverterExtractor.extractData(HttpMessageConverterExtractor.java:108) ~[spring-web-4.0.3.RELEASE.jar:4.0.3.RELEASE] at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:549) ~[spring-web-4.0.3.RELEASE.jar:4.0.3.RELEASE] at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:502) ~[spring-web-4.0.3.RELEASE.jar:4.0.3.RELEASE] at org.springframework.web.client.RestTemplate.getForObject(RestTemplate.java:239) ~[spring-web-4.0.3.RELEASE.jar:4.0.3.RELEASE] at idexx.ordering.services.AwsServersServiceImpl.getBuildInfo(AwsServersServiceImpl.java:96) ~[classes/:na] RE: resttemplate getForObject map responsetype - kerrilljjy - 08-02-2023 I know its old, but just for other people that may visit this topic: If you want to register some additional converters with RestTemplateBuilder you also have to explicitly register default ones @Bean public RestTemplateBuilder builder() { return new RestTemplateBuilder() .defaultMessageConverters() .additionalMessageConverters(halMessageConverter()); } private HttpMessageConverter halMessageConverter() { ObjectMapper objectMapper = new ObjectMapper().registerModule(new Jackson2HalModule()); TypeConstrainedMappingJackson2HttpMessageConverter halConverter = new TypeConstrainedMappingJackson2HttpMessageConverter(ResourceSupport.class); halConverter.setSupportedMediaTypes(Collections.singletonList(MediaTypes.HAL_JSON)); halConverter.setObjectMapper(objectMapper); return halConverter; } RE: resttemplate getForObject map responsetype - mindimindless629 - 08-02-2023 As I had previously noted, your error message is showing us that you are receiving `application/octet-stream` as a `Content-Type`. <!-- language:none --> org.springframework.web.client.RestClientException: Could not extract response: no suitable HttpMessageConverter found for response type [interface java.util.Map] and content type [application/octet-stream] As such, Jackson's `MappingJackson2HttpMessageConverter` cannot parse the content (it's expecting `application/json`). ---------- Original answer: Assuming your HTTP response's `Content-Type` is `application/json` and you have have Jackson 1 or 2 on the classpath, a `RestTemplate` can deserialize JSON like you have into a `java.util.Map` just fine. With the error you are getting, which you haven't shown in full, either you've registered custom `HttpMessageConverter` objects which overwrite the defaults ones, or you don't have Jackson on your classpath and the `MappingJackson2HttpMessageConverter` isn't registered (which would do the deserialization) or you aren't receiving `application/json`. RE: resttemplate getForObject map responsetype - lithochromatics399060 - 08-02-2023 I think you can achieve what you're aiming for simply using the RestTemplate and specifying a JsonNode as the response type. ResponseEntity<JsonNode> response = restTemplate.exchange(url, HttpMethod.GET, entity, JsonNode.class); JsonNode map = response.getBody(); String someValue = map.get("someValue").asText(); RE: resttemplate getForObject map responsetype - digraph315 - 08-02-2023 ***Update 02/05/2018 (about 4 years later)...I tested this again as people have been upvoting my question/answer and Sotirios Delimanolis is correct that I should not have to write the code in my answer to make this work. I used basically the same RestTemplate/REST service setup as shown in my question with the REST service having a confirmed response content type of application/json and RestTemplate was able to process the response with no issues into a Map.*** ---------- I ended up getting the contents as a `String` and then converting them to a `Map` like this: String json = restTemplate.getForObject(buildUrl, String.class); Map<String,String> map = new HashMap<String,String>(); ObjectMapper mapper = new ObjectMapper(); try { //convert JSON string to Map map = mapper.readValue(json, new TypeReference<HashMap<String,String>>(){}); } catch (Exception e) { logger.info("Exception converting {} to map", json, e); } return map; RE: resttemplate getForObject map responsetype - foxtrot690 - 08-02-2023 @GetMapping(value = "getSunny/{userId}") public Map<String, SunnyVO> getSunny(@PathVariable int sunnyId) { Map<String, SunnyVO> newObj = new HashMap<String, SunnyVO>(); final String url = "http://localhost:8085/Sunny/getSunny/{sunnyId}"; RestTemplate restTemplate = new RestTemplate(); newObj = restTemplate.getForObject(url, Map.class, sunnyId); return newObj; } It is working for me ... RE: resttemplate getForObject map responsetype - semillons890188 - 08-02-2023 This worked 100% for me in client Map<String, Object> mapRespuesta = new HashMap<>(); mapRespuesta.put("mensaje", "Process completed successfully"); mapRespuesta.put("idResponse", id); return new ResponseEntity<Map<String, Object>>(mapRespuesta, HttpStatus.OK); in which it makes the connection ResponseEntity<Map> result = restTemplate.postForEntity(url, params, Map.class); String id = result.getBody().get("idResponse").toString(); RE: resttemplate getForObject map responsetype - neognathaezfx - 08-02-2023 **RestTemplate** has a method named **[exchange][1]** that takes an instance of **[ParameterizedTypeReference][2]** as parameter. To make a GET request that returns a `java.util.Map`, just create an instance of an anonym class that inherits from ParameterizedTypeReference. ParameterizedTypeReference<Map<String, String>> responseType = new ParameterizedTypeReference<>() {}; You can then invoke the exchange method: RequestEntity<Void> request = RequestEntity.get("http://example.com/foo") .accept(MediaType.APPLICATION_JSON).build(); Map<String, String> jsonDictionary = restTemplate.exchange(request, responseType).getBody(); [1]: [To see links please register here] -[2]: [To see links please register here] |