为什么我在尝试使用HttpURLConnection上传文件时从服务器收到错误响应

Question

我试图将文件上传到服务器（不是我的）我想我确实做了它所需要的但如果我做错了请有人纠正我

这是API

POST https://i cant share the URL HTTP/1.1
Content-Type: multipart/form-data;
boundary=----------------------------8d19a412e59ea7e
User-Agent: Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/36.0.1985.143 Safari/537.36
Content-Length: 567460
Expect: 100-continue
Connection: Keep-Alive
------------------------------8d19a412e59ea7e
Content-Disposition: form-data; name="filename"; filename="report.xml"
Content-Type: application/xml

我的要求

private String uploadFile(String sourceFile,url)
        throws ClientProtocolException, IOException {
    FileInputStream fileInputStream = new FileInputStream(sourceFile);
    HttpURLConnection conn;
    DataOutputStream dos = null;
    String lineEnd = "\r\n";
    String twoHyphens = "--";
    String boundary = "--------------------------8d19a412e59ea7e";
    int bytesRead, bytesAvailable, bufferSize;
    byte[] buffer;
    int maxBufferSize = 1 * 1024 * 1024;
    // Open a HTTP connection to the URL
    conn = (HttpURLConnection) url.openConnection();
    conn.setDoInput(true); // Allow Inputs
    conn.setDoOutput(true); // Allow Outputs
    conn.setUseCaches(false); // Don't use a Cached Copy
    conn.setRequestMethod("POST");
    conn.setRequestProperty("Connection", "Keep-Alive");
    conn.setRequestProperty("ENCTYPE", "multipart/form-data");
    conn.setRequestProperty("Content-Type", "multipart/form-data;boundary="
        + boundary);
    conn.setRequestProperty("uploaded_file", "");

    dos = new DataOutputStream(conn.getOutputStream());

    dos.writeBytes(boundary + lineEnd);
    dos.writeBytes("Content-Disposition: form-data; name=fileName;fileName=" + sourceFile+ boundary);

    dos.writeBytes(lineEnd);

    // create a buffer of maximum size
    bytesAvailable = fileInputStream.available();

    bufferSize = Math.min(bytesAvailable, maxBufferSize);
    buffer = new byte[bufferSize];

    bytesRead = fileInputStream.read(buffer, 0, bufferSize);

    while (bytesRead > 0) {

        dos.write(buffer, 0, bufferSize);
        bytesAvailable = fileInputStream.available();
        bufferSize = Math.min(bytesAvailable, maxBufferSize);
        bytesRead = fileInputStream.read(buffer, 0, bufferSize);

    }

    // send multipart form data necesssary after file data...
    dos.writeBytes(lineEnd);
    dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);

    // Responses from the server (code and message)

    String serverResponseMessage = conn.getResponseMessage();
    int responseCode = conn.getResponseCode();
    BufferedReader br = new BufferedReader(new InputStreamReader(
        (conn.getInputStream())));
    String inputLine = null;
    while ((inputLine = br.readLine()) != null)
        System.out.println(inputLine);
    return serverResponseMessage;
}