Spring restTemplate issue in getting response

Question

My rest server is generating response when I called it with rest client software. When I call it with resttemplate code mentioned above, then server generates response(print logs) but resttemplate does nothing(no next line executes after call) and prints internal error .

This is the method in my server

@ResponseBody
public ResponseEntity<Map<String, Object>> name(){......
...
return new ResponseEntity<Map<String, Object>>(messagebody, HttpStatus.OK);
}

This is the way I am calling it through restTemplate

ResponseEntity<Map> response1 = restTemplate.getForEntity(finalUrl.toString(), Map.class);

Answer 1

Try to use ParameterizedTypeReference instead of wildcarded Map . It should looks like this.

ParameterizedTypeReference<Map<String, Object>> typeRef = new ParameterizedTypeReference<Map<String, Object>>() {};

ResponseEntity<Map<String, Object>> response = restTemplate.exchange(finalUrl.toString(), HttpMethod.GET, null, typeRef);

Answer 2

this is a example that works for me

@RequestMapping(value = "/getParametros/{instancia}", method = RequestMethod.GET, produces = MediaType.TEXT_PLAIN_VALUE)
public ResponseEntity<String> getParametros(@PathVariable String instancia)
{
    LOG.debug("REST. Obteniendo parametros del servidor " + instancia);
    Map<String, String> mapa = parametrosService.getProperties(instancia);
    HttpHeaders headers = new HttpHeaders();
    headers.add("Content-Type", "application/json; charset=UTF-8");
    headers.add("X-Fsl-Location", "/");
    headers.add("X-Fsl-Response-Code", "302");
    ObjectMapper mapper = new ObjectMapper();

    String s = "";
    try
    {
        s = mapper.writeValueAsString(mapa);
    } catch (JsonProcessingException e)
    {
        LOG.error("NO SE PUEDE MAPEAR A JSON");
    }

    if (mapa == null)
        return new ResponseEntity<String>(HttpStatus.BAD_REQUEST);

    return new ResponseEntity<String>(s, headers, HttpStatus.OK);
}

Answer 3

you can Catch the HttpStatusCodeException from which you can get response in String . below code works for me.

restTemplate.postForObject( url, jsonRequest, ResponseData.class );
catch( HttpStatusCodeException codeException )
{
    String payload = codeException.getResponseBodyAsString();
    System.out.println( payload );

}