Android HttpURLConnection图片上传但文件无法识别为JPEG

问题描述

我有这个代码，它能够将JPEG文件上传到服务器，但文件不能识别为JPEG。 我认为我的问题是正确编码JPEG文件。 我的解决方案与解决方案基本相同。 我尝试使用FileInputStream附加JPEG字节并使用DataOutputStream而不是OutputStreamWriter等其他变体无济于事。 任何建议表示赞赏。

final String boundary = "==================";
final String mimeType = "image/jpeg";
final int IMAGE_QUALITY = 100;

URL url = null;
HttpURLConnection urlConnection = null;
OutputStreamWriter request = null;
String response = null;

try {
    url = new URL(params[0]);
    urlConnection = (HttpURLConnection) url.openConnection();
    urlConnection.setDoOutput(true);
    urlConnection.setDoInput(true);     ///
    urlConnection.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary);
    urlConnection.setRequestMethod("POST");

    OutputStream outputStream= urlConnection.getOutputStream();

    request = new OutputStreamWriter(outputStream);
    request.append("--" + boundary).append("\n");
    request.append("Content-Disposition: form-data; name=\"file\"; filename=\"" + imageFileName + "\"").append("\n\n");
    request.append("Content-Type: " + mimeType).append("\n\n");
    request.append("Content-Encoding: base64").append("\n\n");

    ByteArrayOutputStream stream = new ByteArrayOutputStream();
    imageThumbnail.compress(Bitmap.CompressFormat.JPEG, IMAGE_QUALITY, stream);
    byte[] byteArray = stream.toByteArray();
    //request.append(new String(byteArray)).append("\n");
    String encodedImage = Base64.encodeToString(byteArray, Base64.DEFAULT);
    request.append(encodedImage);

    request.append("--" + boundary + "--");
    request.flush();
    request.close();

    String line = null;
    InputStreamReader isr = new InputStreamReader(urlConnection.getInputStream());
    BufferedReader reader = new BufferedReader(isr);
    StringBuilder sb = new StringBuilder();
    while ((line = reader.readLine()) != null) {
        sb.append(line).append("\n");
    }
    response = sb.toString();   // = "Success"

    isr.close();
    reader.close();

} catch (MalformedURLException e) {
    e.printStackTrace();
    response = "Malformed URL";

} catch (IOException e) {
    e.printStackTrace();
    response = "IO Exception";
}

return response;