可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试):

问题:

Am trying to upload a large file using the 'streaming' Apache Commons File Upload API.

The reason I am using the Apache Commons File Uploader and not the default Spring Multipart uploader is that it fails when we upload very large file sizes (~2GB). I working on a GIS application where such file uploads are pretty common.

The full code for my file upload controller is as follows:

@Controller
public class FileUploadController {

    @RequestMapping(value="/upload", method=RequestMethod.POST)
    public void upload(HttpServletRequest request) {
        boolean isMultipart = ServletFileUpload.isMultipartContent(request);
        if (!isMultipart) {
            // Inform user about invalid request
            return;
        }

        //String filename = request.getParameter("name");

        // Create a new file upload handler
        ServletFileUpload upload = new ServletFileUpload();

        // Parse the request
        try {
            FileItemIterator iter = upload.getItemIterator(request);
            while (iter.hasNext()) {
                FileItemStream item = iter.next();
                String name = item.getFieldName();
                InputStream stream = item.openStream();
                if (item.isFormField()) {
                    System.out.println("Form field " + name + " with value " + Streams.asString(stream) + " detected.");
                } else {
                    System.out.println("File field " + name + " with file name " + item.getName() + " detected.");
                    // Process the input stream
                    OutputStream out = new FileOutputStream("incoming.gz");
                    IOUtils.copy(stream, out);
                    stream.close();
                    out.close();

                }
            }
        }catch (FileUploadException e){
            e.printStackTrace();
        }catch (IOException e){
            e.printStackTrace();
        }
    }

    @RequestMapping(value = "/uploader", method = RequestMethod.GET)
    public ModelAndView uploaderPage() {
        ModelAndView model = new ModelAndView();
        model.setViewName("uploader");
        return model;
    }

}

The trouble is that the getItemIterator(request) always returns an iterator that does not have any items (i.e. iter.hasNext() ) always returns false.

My application.properties file is as follows:

spring.datasource.driverClassName=org.postgresql.Driver
spring.datasource.url=jdbc:postgresql://localhost:19095/authdb
spring.datasource.username=georbis
spring.datasource.password=asdf123

logging.level.org.springframework.web=DEBUG

spring.jpa.hibernate.ddl-auto=update

multipart.maxFileSize: 128000MB
multipart.maxRequestSize: 128000MB

server.port=19091

The JSP view for the /uploader is as follows:

<html>
<body>
<form method="POST" enctype="multipart/form-data" action="/upload">
    File to upload: <input type="file" name="file"><br />
    Name: <input type="text" name="name"><br /> <br />
    Press here to upload the file!<input type="submit" value="Upload">
    <input type="hidden" name="${_csrf.parameterName}" value="${_csrf.token}" />
</form>
</body>
</html>

What might I be doing wrong?

回答1:

Thanks to some very helpful comments by M.Deinum, I managed to solve the problem. I have cleaned up some of my original post and am posting this as a complete answer for future reference.

The first mistake I was making was not disabling the default MultipartResolver that Spring provides. This ended up in the resolver processing the HttpServeletRequest and thus consuming it before my controller could act on it.

The way to disable it, thanks to M. Deinum was as follows:

multipart.enabled=false

However, there was still another hidden pitfall waiting for me after this. As soon as I disabled default multipart resolver, I started getting the following error when trying to make an upload:

Fri Sep 25 20:23:47 IST 2015
There was an unexpected error (type=Method Not Allowed, status=405).
Request method 'POST' not supported

In my security configuration, I had enabled CSRF protection. That necessitated that I send my POST request in the following manner:

<html>
<body>
<form method="POST" enctype="multipart/form-data" action="/upload?${_csrf.parameterName}=${_csrf.token}">
    <input type="file" name="file"><br>
    <input type="submit" value="Upload">
</form>
</body>
</html>

I also modified my controller a bit:

@Controller
public class FileUploadController {
    @RequestMapping(value="/upload", method=RequestMethod.POST)
    public @ResponseBody Response<String> upload(HttpServletRequest request) {
        try {
            boolean isMultipart = ServletFileUpload.isMultipartContent(request);
            if (!isMultipart) {
                // Inform user about invalid request
                Response<String> responseObject = new Response<String>(false, "Not a multipart request.", "");
                return responseObject;
            }

            // Create a new file upload handler
            ServletFileUpload upload = new ServletFileUpload();

            // Parse the request
            FileItemIterator iter = upload.getItemIterator(request);
            while (iter.hasNext()) {
                FileItemStream item = iter.next();
                String name = item.getFieldName();
                InputStream stream = item.openStream();
                if (!item.isFormField()) {
                    String filename = item.getName();
                    // Process the input stream
                    OutputStream out = new FileOutputStream(filename);
                    IOUtils.copy(stream, out);
                    stream.close();
                    out.close();
                }
            }
        } catch (FileUploadException e) {
            return new Response<String>(false, "File upload error", e.toString());
        } catch (IOException e) {
            return new Response<String>(false, "Internal server IO error", e.toString());
        }

        return new Response<String>(true, "Success", "");
    }

    @RequestMapping(value = "/uploader", method = RequestMethod.GET)
    public ModelAndView uploaderPage() {
        ModelAndView model = new ModelAndView();
        model.setViewName("uploader");
        return model;
    }
}

where Response is just a simple generic response type I use:

public class Response<T> {
    /** Boolean indicating if request succeeded **/
    private boolean status;

    /** Message indicating error if any **/
    private String message;

    /** Additional data that is part of this response **/
    private T data;

    public Response(boolean status, String message, T data) {
        this.status = status;
        this.message = message;
        this.data = data;
    }

    // Setters and getters
    ...
}

回答2:

If you're using a recent version of spring boot (I'm using 2.0.0.M7) then the property names have changed. Spring started using technology specific names

spring.servlet.multipart.maxFileSize=-1

spring.servlet.multipart.maxRequestSize=-1

spring.servlet.multipart.enabled=false

If you're getting StreamClosed exceptions caused by multiple implementations being active, then the last option allows you to disable the default spring implementation

回答3:

Please try to add spring.http.multipart.enabled=false in application.properties file.

回答4:

I use kindeditor + springboot. When I use (MultipartHttpServletRequest) request. I could get the file, but I use appeche-common-io:upload.parse(request) the return value is null.

public BaseResult uploadImg(HttpServletRequest request,String type){
                MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;
                MultiValueMap<String, MultipartFile> multiFileMap = multipartRequest.getMultiFileMap();