Spring MVC @RequestBody gives me an empty string when used with @RequestParam MultipartFile

Question

I have a problem with this web service code

@Controller @RequestMapping("/u_tutorial") public class UploadTutorial { @RequestMapping(value = "tutorial1", method = RequestMethod.POST, headers = "Accept=application/json") @ResponseStatus(value = HttpStatus.OK) public void upload(@RequestBody String body, @RequestParam List<MultipartFile> file, Principal principal, HttpServletRequest request) { System.out.println("body: " + body); // always empty for (MultipartFile mf : file) { System.out.println("file: " + mf.getOriginalFilename()); } } } 

The situation is when I want to upload files with some data to the request body, my body variable always gives me an empty string.

But when I try to use only the "body of the string @RequestBody" or the "list file @RequestParam", it works like a charm.

I did a few searches and found that this was due to the InputStream problem. Some proposed solution has already been discussed, but is not entirely related to my problem (or maybe yes, but I do not understand).

Can someone give me a solution? thanks.

PS 1. here is my version of the library

 <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <spring.core.version>3.1.4.RELEASE</spring.core.version> <spring.security.version>3.1.3.RELEASE</spring.security.version> <spring.data.mongodb.version>1.1.0.RELEASE</spring.data.mongodb.version> <cglib.version>2.2</cglib.version> <aspectj.version>1.6.10</aspectj.version> <mongodb.driver.version>2.10.1</mongodb.driver.version> <!-- Logging --> <slf4j.version>1.6.1</slf4j.version> <log4j.version>1.2.14</log4j.version> <javax.jstl-taglibs.version>1.1.2</javax.jstl-taglibs.version> <jackson.version>1.9.3</jackson.version> <!-- Testing --> <mockito.version>1.8.5</mockito.version> <junit.version>4.8.2</junit.version> <!-- Plugins --> <maven.copy.plugin.version>0.2.3</maven.copy.plugin.version> <maven.compiler.plugin.version>2.3.2</maven.compiler.plugin.version> <maven.apt.plugin.version>1.0</maven.apt.plugin.version> <!-- Utilities --> <apache.common.io.version>2.4</apache.common.io.version> <apache.common.fileupload.version>1.2.2</apache.common.fileupload.version> <jodatime.version>2.1</jodatime.version> </properties> 

PS 2. Sorry for my English.

Answer 1

You can make the "body" line a hidden field in the form and place it as another @RequestParam, and not have it as a separate @RequestBody parameter. Thus, your form will look something like this:

 <form id="myForm" method="post" enctype="multipart/form-data"> <input type="hidden" name="body" value="bodyValue"/> <input type="file" name="file"/> ... 

The controller will look like this:

 public void upload(@RequestParam String body, @RequestParam List<MultipartFile> file, Principal principal, HttpServletRequest request) .... 

Answer 2

I thought about my question from different points of view and found that perhaps the client cannot upload files and send data to @RequestBody at the same time.

So, I started to catch the request using WireShark. The result was as I expected. No data available. Only files remain in the request.

Link: Posting a file and related data to a RESTful WebService, preferably as JSON

The solution may be to rebuild my web service server.

thanks.