Question

I am trying to upload a file to the server directory from client machine. I used the following codes :

FileUpload.jsp

<form:form commandName="fileUpload" action="upload.action" method="post"  enctype="multipart/form-data">
<form:label path="fileData">Upload a File</form:label> <br />
<form:input type="file"  path="fileData" />
<input type="submit" value="upload" >
</form:form>

In my Controller:

@RequestMapping("/upload.action")
public String upload(@ModelAttribute("fileUpload") FileUpload fileUpload,HttpServletResponse response,Model model)
{
    CommonsMultipartFile multipartFile = fileUpload.getFileData();
    String orginalName = multipartFile.getOriginalFilename();
    String filePath = "/my_uploads/"+orginalName;
    File destination = new File(filePath);
    String status ="success";
    try {
        multipartFile.transferTo(destination);
    } catch (IllegalStateException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        status="failure";
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        status="iofailure";
    }
    model.addAttribute("status", status);
    return "home";
}

FileUpload.java :

{
   private CommonsMultipartFile fileData;
   ....
}

NullPointerException is thrown at the line String orginalName = multipartFile.getOriginalFilename(); .. what wrong thing i have done??

Answer 1

Try adding the MultipartFile as a parameter in your requesthandler.

@RequestMapping("/upload.action")
public String upload(@RequestParam(value = "file") MultipartFile file,
        HttpServletResponse response,Model model)
{
    //Controller logic...
}

This will require you to register a new bean in your dispatcher’s configuration.

<bean id="multipartResolver"
   class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    <property name="maxUploadSize" value="5000000"/>
</bean>