java - 如何使用 wicket 将大文件上传到 google cloud

Question

我尝试使用 wicket 在谷歌云上上传一个大文件。我使用 FileUploadField 和 UploadFile 方法。不过我只能上传小文件(小于 10kb)。如果我上传更大的文件，我会得到一个异常(java.security.AccessControlException:访问被拒绝)。我没有创建缓冲文件和写入的权限。

final FileUploadField FiletoUpload = new FileUploadField("uploadfile", new Model());
    form.add(FiletoUpload);

    form.add(new Button("upload") {

        @Override
        public void onSubmit() {

            //here we upload
            getRequestCycle().scheduleRequestHandlerAfterCurrent(new IRequestHandler() {

                @Override
                public void respond(IRequestCycle irc) {

                    FileUpload uploadedFile = FiletoUpload.getFileUpload();
                    HttpServletResponse httpResponse = (HttpServletResponse) irc.getResponse().getContainerResponse();

                    InputStream CORPUS = null;
                    try {
                        CORPUS = uploadedFile.getInputStream();

                    } catch (IOException ex) {
                        Logger.getLogger(Upload.class.getName()).log(Level.SEVERE, null, ex);
                    }

                    try {
                       doGet(null, httpResponse);
                    } catch (IOException ex) {
                        Logger.getLogger(Upload.class.getName()).log(Level.SEVERE, null, ex);
                    }
                    uploadedFile.closeStreams();
                }

                @Override
                public void detach(IRequestCycle irc) {
                }
            });
        }
    });

我不使用 blobstore，我使用 com.google.appengine.tools.cloudstorage.*。我开个 channel 写在云端。

public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
    resp.setContentType("text/plain");
    GcsService gcsservice = GcsServiceFactory.createGcsService();
    GcsFilename uploadfile = new GcsFilename(BUCKETNAME, FILENAME);
    GcsFileOptions optionsBuilder = new GcsFileOptions.Builder()
            .mimeType("text/plain")
            .acl("bucket-owner-full-control")
            .build();

    GcsOutputChannel writechannel = gcsservice.createOrReplace(uploadfile, optionsBuilder );

    buffer = new StringBuffer();
    int char_read = 0;
    long i;
    for(i=0; i< CORPUSsize; i++){
        char_read = CORPUS.read(); //I read the corpus of the file
        char mychar = (char) char_read;
        buffer.append(mychar);
    }

    writechannel.write(ByteBuffer.wrap(buffer.toString().getBytes("UTF-8")));
    writechannel.close();

}

有没有获取权限异常的情况下上传大文件的解决方案？

Answer 1

Wicket 使用 DiskFileItemFactory，它在 10240 字节阈值后将文件存储在磁盘上。

您必须更改 sizeThreshold 或使用 FileItemFactory 的替代实现。请参阅 MultipartServletWebRequestImpl 构造函数。