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Spring 3.0 Download MultipartFile

I am converting a Java web application into a Spring framework and appreciate some tips on the issues that I have to deal with when downloading files. The source code was written using org.apache.commons.fileupload.

  • Can Spring MultipartFile wrap org.apache.commons.fileupload or can I exclude this dependency from my POM file?

  • I saw the following example:

    @RequestMapping(value = "/form", method = RequestMethod.POST)
public String handleFormUpload(@RequestParam("file") MultipartFile file) {

    if (!file.isEmpty()) {
        byte[] bytes = file.getBytes();
        // store the bytes somewhere
       return "redirect:uploadSuccess";
    } else {
        return "redirect:uploadFailure";
    }
}

    Initially, I tried to follow this example, but always got an error, because I could not find this query parameter. So, in my controller, I did the following:

    @RequestMapping(value = "/upload", method = RequestMethod.POST)
public @ResponseBody
ExtResponse upload(HttpServletRequest request, HttpServletResponse response)
{
   // Create a JSON response object.
   ExtResponse extResponse = new ExtResponse();
   try {
       if (request instanceof MultipartHttpServletRequest)
       {
           MultipartHttpServletRequest multipartRequest =
                        (MultipartHttpServletRequest) request;
           MultipartFile file = multipartRequest.getFiles("file");
           InputStream input = file.getInputStream();
           // do the input processing
           extResponse.setSuccess(true);
        }
    } catch (Exception e) {
        extResponse.setSuccess(false);
        extResponse.setMessage(e.getMessage());
    }
    return extResponse;
}

and it works. If someone tells me why @RequestParam does not work for me, I would appreciate it. BTW I have

    <bean id="multipartResolver"
        class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="maxUploadSize" value="2097152"/>
    </bean>

in my servlet context file.

+3
source share
6
  • spring shareons-fileupload, . , spring
  • MultipartFile , @RequestParam(..)
+2

  • shareup-fileupload pom,
  • multipartResolver bean ( ),
  • @RequestParam ( "file" ) MultipartFile handleFormUpload
  • enctype my jsp: <form:form method="POST" action="/form" enctype="multipart/form-data" >

.

+2

.

@RequestMapping(value = "upload.spr", method = RequestMethod.POST)
public ModelAndView upload(@RequestParam("file") MultipartFile file, HttpServletResponse response)
{
    //  handle file here
}
+1

sysntax - @RequestParam (value = " ", = true), mode over request param frm Url.

0

In POST, you will send parameters only to the request body, not to the URL (for which you use @RequestParams)

That is why your second method worked.

0
source

Spring introduced MVC 3.2 support for Servet 3.0. Therefore, you must enable the download of public files if you are using earlier versions of Spring.

0
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