java输入流无限循环

Question

我正在尝试将一个文件从Android上传到运行Jersey的Tomcat服务器。我把它包装在一个Post请求中

这就是我在Android中所做的：

protected String doInBackground(String... params) {
    String url = params[0];
    String pathToFile = params[1];
    HttpClient httpClient = new DefaultHttpClient();
    HttpContext localContext = new BasicHttpContext();
    HttpPost httpPost = new HttpPost();
    HttpResponse response = null;
    httpPost.addHeader("Cookie", "sessionToken=~session");
    try {
        httpPost.setURI(new URI(url));
        httpPost.setHeader("Accept", "application/json");
        MultipartEntity entity = new MultipartEntity(
                HttpMultipartMode.BROWSER_COMPATIBLE);
        File file = new File(pathToFile);
        if(!file.exists())
            return null;
        FileBody fileBody = new FileBody(file);
        entity.addPart("file", fileBody);
        httpPost.setEntity(entity);

        response = httpClient.execute(httpPost);
        HttpEntity result = response.getEntity();
    } catch (ClientProtocolException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (URISyntaxException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch(Exception e){
        e.printStackTrace();
    }
    return response.getStatusLine().toString();

在服务器中，我有以下内容：

我收到一个类型为“org.jvnet.mimepull.DataHead$ReadMultiStream”的InputStream，在读取时，在到达文件末尾后，读取返回到1024

@POST
@Consumes({ MediaType.MULTIPART_FORM_DATA })
@Produces({ MediaType.APPLICATION_JSON })
public Response uploadStorageFile(@Context UriInfo ui, @Context HttpHeaders hh, @FormDataParam("file") 
InputStream uploadedInputStream, @FormDataParam("file") FormDataContentDisposition fileDetail){
    System.out.println(uploadedInputStream.getClass().getName());
    String uploadedFileLocation = fileDetail.getFileName();
    long size = fileDetail.getSize();
    // save it
    writeToFile(uploadedInputStream);

    String output = "File uploaded to : ";

    return Response.status(200).entity(output).build();

}
private void writeToFile(InputStream uploadedInputStream) {

        try {
            OutputStream out = new FileOutputStream(new File("test.jpg"));
            int read = 0;
            byte[] bytes = new byte[1024];
            while ((read = uploadedInputStream.read(bytes)) > 0) {
                out.write(bytes, 0, read);
            }
            out.flush();
            out.close();
        } catch (IOException e) {

            e.printStackTrace();
        }

    }

如果文件长度为8192，则循环如下： 102420483072409651206144716881921024->；为什么?

注意：我已尝试使用-1条件

有人知道发生了什么事吗

Answer 1

既然这帮你解决了问题，你最近的评论表明this bug was responsible.

Both methods "read" on ReadMultiStream class violate contract of the implemented interface java.io.InputStream. Javadoc states, that -1 should be returned at the end of the stream, but ReadMultiStream class returns -1 only for the first call (at the end of the stream), all subsequent calls throw an exception instead. This problem could be simulated by sending a stream of characters over web service and wrapping it to the java.io.BufferedReader on the client side. When the stream doesn't end with a new line character, then the usual usage of method readLine fails.

Fix Version/s: 2.2.6

Answer 2

多亏了@Jonathan Drapeau，@boxed|才发现了问题。ReadMultiStream违反了java规范。伊奥。输入流接口

解决方案非常简单，服务器端：

@POST
@Consumes({ MediaType.MULTIPART_FORM_DATA })
@Produces({ MediaType.APPLICATION_JSON })
public Response uploadStorageFile(@Context UriInfo ui, @Context HttpHeaders hh,     @FormDataParam("file") 
InputStream uploadedInputStream, @FormDataParam("file") FormDataContentDisposition fileDetail){
System.out.println(uploadedInputStream.getClass().getName());
String uploadedFileLocation = fileDetail.getFileName();
long size = fileDetail.getSize();
// save it
try {
            //test.jpg for test purposes
    OutputStream out = new FileOutputStream(new File("test.jpg")); 
    IOUtils.copy(uploadedInputStream, out);
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

String output = "File uploaded to : ";

return Response.status(200).entity(output).build();

}

正如我在问题中提供的那样，多个教程都在教授如何使用inputstream（服务器端），因此我不知道这是否是最近出现的错误