Android：未从网址下载完整文件

Question

In my app, I have requirement to download mp3 files from url. I am downloading file using Async Task. For testing purpose, I have kept file in dropbox. The problem is, it is not downloading complete file. The actual file size is of 5 MB. But, it is downloading only 29 KB of data. When I checked the length of content, it showed -1. I am not getting where is the problem. Below, I am posting my code.

@Override
    protected Void doInBackground(String... sUrl) 
    {
        InputStream input = null;
        OutputStream output = null;
        try 
        {
            URL link = new URL(sUrl[0]);
            HttpURLConnection urlConnection = (HttpURLConnection)link.openConnection();
            urlConnection.setRequestMethod("GET");
            urlConnection.setDoOutput(true);
            urlConnection.connect();
            int fileLength = urlConnection.getContentLength();
            Log.v("Download file length", ""+fileLength);
            input = urlConnection.getInputStream();
            int downloadedSize = 0;
            output = new FileOutputStream(Environment.getExternalStorageDirectory()
                    .getAbsolutePath()+"/audiofolder/1.mp3.mp3");

            byte[] data = new byte[1024];
            int bufferLength = 0;

            while (((bufferLength = input.read(data)) > 0)) 
            {
                output.write(data, 0, bufferLength);
                downloadedSize += bufferLength;
                publishProgress((int)((downloadedSize/fileLength) * 100));
            }//while
            output.flush();
            output.close();
            input.close();
        }//try 
        catch (MalformedURLException e) 
        {
            e.printStackTrace();
        }//catch
        catch (IOException e) 
        {
            e.printStackTrace();
        }//catch
        return null;
    }//diInBackground

Answer 1

in My Application the Below Code Works Perfectly. you can try this Out.

    @Override
    protected Void doInBackground(String... aurl) {

        try {

            URL url = new URL(aurl[0]);
            URLConnection conexion = url.openConnection();
            conexion.connect();

            File file = new File("mnt/sdcard/");
            file.mkdirs();
            File outputfile = new File(file, title + ".mp3");
            FileOutputStream fileOutput = new FileOutputStream(outputfile);
            InputStream inputStream = conexion.getInputStream();
            int totalSize = conexion.getContentLength();
            int downloadedSize = 0;
            byte[] buffer = new byte[1024];
            int bufferLength = 0;  
            while ((bufferLength = inputStream.read(buffer)) != -1) {
                downloadedSize += bufferLength;
                onProgressUpdate((int) ((downloadedSize * 100) / totalSize));
                fileOutput.write(buffer, 0, bufferLength);
            }
            fileOutput.close();
        } catch (Exception e) {
            download = true;
            e.printStackTrace();

        }
        return null;

    }

Answer 2

Check your link. When you see length of content = -1, it mean there is no length of content in header of link. It don't force under your download progress. You only download 29KB because it download website, .html not file mp3. Yout can copy and paste your link on brower to check.

Answer 3

From Android Documentation:

https://developer.android.com/reference/java/net/URLConnection.html#getContentLength()

getContentLength returns:

the content length of the resource that this connection's URL references, -1 if the content length is not known, or if the content length is greater than Integer.MAX_VALUE.