带有多部分请求的android rest模板

Question

case 1 : send Entity class as request [working]

case 2 : send image(multipart) as request [working]

case 3 : send entity + image [not working]

case 1 :

@RequestMapping(value = "/add", method = RequestMethod.POST)
public @ResponseBody String add(@RequestBody SampleEntity sampleEntity) {
    return "From Server: " + sampleEntity.getId();
}

test case 1

sampleEntity.setId(123);
String response1 = restTemplate.postForObject(SERVER_URI+"add", sampleEntity, String.class);
System.out.println(response1);

Output : From Server: 123

case 2 :

@RequestMapping(value = "/imagepart", method = RequestMethod.POST)
public @ResponseBody String imagePart(@RequestPart("image") MultipartFile file) {
    return "From Server(ImagePart): " + file.getOriginalFilename();
}

test case 2

MultiValueMap<String, Object> part1 = new LinkedMultiValueMap<String, Object>();
    part1.add("image", new FileSystemResource("C:\\Users\\Public\\Pictures\\Sample Pictures\\Koala.jpg"));
    String response2 = restTemplate.postForObject(SERVER_URI+"imagepart", part3,  String.class);
    System.out.println(response2);

Output : From Server(ImagePart): Koala.jpg

case 3 :

@RequestMapping(value = "/addimagepart", method = RequestMethod.POST)
public @ResponseBody String addPart(
        @RequestPart("sampleEntity") SampleEntity sampleEntity,
        @RequestPart("image") MultipartFile file) {

    return "From Server(Part) : " + sampleEntity.getId() + " "
            + file.getOriginalFilename();

}

test case 3

  sampleEntity.setId(2);
  part.add("sampleEntity",sampleEntity);
  part.add("image", new FileSystemResource("C:\\Users\\Public\\Pictures\\Sample Pictures\\Desert.jpg"));
  String response2 = restTemplate.postForObject(SERVER_URI+"addimagepart", part, String.class);
    System.out.println(response2);

Error : this case failed (entity class with image not working)

how to make request Entity + Multipart Request from android rest template to spring mvc server

Answer 1

In case 3 the FormHttpMessageConverter is used to convert MultiValueMap objects for sending in HTTP requests. Unfortunately, default FormHttpMessageConverter does not support conversion of entities to JSON. Thus, You have to add some JSON converter (eg MappingJackson2HttpMessageConverter ) to FormHttpMessageConverter manually. Try to use this code:

FormHttpMessageConverter converter = new FormHttpMessageConverter();
converter.addPartConverter(new MappingJackson2HttpMessageConverter());
restTemplate.getMessageConverters().add(0, converter);

Answer 2

Instead of Multipartfile annotation, fetch multipart-data from request object

if (request instanceof MultipartHttpServletRequest) {
            MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;

            Set set = multipartRequest.getFileMap().entrySet();
            Iterator i = set.iterator();
            while (i.hasNext()) {
                Map.Entry me = (Map.Entry) i.next();
                System.out.println("key :" + me.getKey() + "-"
                        + me.getKey().getClass() + "|||||" + "value :"
                        + me.getValue() + "-" + me.getValue().getClass());
                switch ((String) me.getKey()) {
                case "staffPhoto": {
                    System.out.println("case staffImage "
                            + ((MultipartFile) me.getValue())
                                    .getOriginalFilename());
                    // processImage
                    break;
                }
}