Check programmatically if a downloaded MP3/OGG file is valid/complete in android

Question

I am downloading audio files MP3/ OGG programmatically from user provided URLs. I further would proceed to set the downloaded files as ringtone/alarmtone. However, I need to programmatically verify that the file downloaded is a valid MP3/OGG file and is playable. What way can I make sure that the file that has been downloaded is a valid MP3/OGG file and not a junk header from a fake URL.

Code I am using to download :

try {
        URL url = new URL(link);
        httpConn = (HttpURLConnection) url.openConnection();
        httpConn.setRequestMethod("GET");
        httpConn.setReadTimeout(20000);
        httpConn.setConnectTimeout(10000);
        httpConn.connect();
        int responseCode = httpConn.getResponseCode();
        if (responseCode != HttpURLConnection.HTTP_OK) {
            Log.i(TAG, "http response error code "+responseCode+" for "+name);
            return -1;
        }

        int lenghtOfFile = httpConn.getContentLength();
        Log.d(TAG, "Length of file to download: " + lenghtOfFile + " for " + name + " id_download "+id_download);
        if (lenghtOfFile == -1) {
            return -1; // no length to download
        }
        // input stream to read file - with 8k buffer
        input = new BufferedInputStream(httpConn.getInputStream(),1000000);

        // Delete the outfile first
        File deleteFile = new File(outfile);
        if (deleteFile.exists()) {
            if (deleteFile.delete())
                Log.i(TAG, "File deleted " + outfile);
            else
                Log.i(TAG, "File could'nt be deleted " + outfile);
        }

        output = new FileOutputStream(outfile);
        byte data[] = new byte[1000000];

        long total = 0;
        int progress = 0;
        long mLastUpdate = 0;

        int count = 0;
        while ((count = input.read(data)) != -1) {
            total += count;
            progress = (int) ((total * 100) / lenghtOfFile);
            Log.d(TAG, name + " progress " + progress+"  count "+count+" total "+total);
            output.write(data, 0, count);
            if (System.currentTimeMillis() - mLastUpdate > 1000) {
                mLastUpdate = System.currentTimeMillis();
            }
        }

        output.flush();
    } catch (Exception e) {
        Log.e(TAG, "Exception in downloadUrl() " + e + " for " + name + "  " + id_download + "  "+task_id);
        return -1;
    } finally {
        try {
            if (output != null) {
                output.close();
            }
            if (input != null) {
                input.close();
            }
            if (httpConn != null) {
                httpConn.disconnect();
            }
        } catch (Exception ex) {
            Log.e(TAG,"Exception in close "+ex);
        }
    }

Answer 1

You can check for the End of the download stream, if it is called, its an indication, your files downloaded with complete length. Accept this answer if it works for you? Thanks

Answer 2

I resolved the issue by using MediaMetadataRetriever classe's API "extractMetadata(MediaMetadataRetriever.METADATA_KEY_DURATION)". This returns a valid duration if its a valid mp3/ ogg file. Else I catch a runtime exception and return from my API.