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How to programatically download files with increased speed in android

Hi have implemented programatically downloading of file using inputstream and cipheroutputstream(for encryption). The download is happening very slow. Whereas if i try to download via download manager, it is very fast. What can i do to improve my code and increase the download speed of the file. Below is my code.
private void saveFileUsingEncryption(String aMineType, long length) throws Exception {
int bufferSize = 1024*4;
//byte[] buffer = new byte[1024];
byte[] buffer = new byte[bufferSize];
int bytesRead = 0;
long totalRead = 0;
FileOutputStream outStream = null;
File f = new File(Constants.DWLPATH);
if (!f.exists()) {
f.mkdirs();
}
try {
Cipher aes = Cipher.getInstance("ARC4");
aes.init(Cipher.ENCRYPT_MODE, new SecretKeySpec("mykey".getBytes(), "ARC4"));
if(contDisp==null || contDisp.length()==0) {
// downloadFileName = downloadFileName.replaceAll("[^a-zA-Z0-9_]+", "");
downloadFileName = downloadFileName + "." + getFileExtension(aMineType);
}
outStream = new FileOutputStream(Constants.DWLPATH + downloadFileName,true);
CipherOutputStream out = new CipherOutputStream(outStream, aes);
while ((bytesRead = inputStream.read(buffer, 0, bufferSize)) >= 0) {
out.write(buffer, 0, bytesRead);
try{
// Adjust this value. It shouldn't be too small.
Thread.sleep(50);
}catch (InterruptedException e){
TraceUtils.logException(e);
}
totalRead += bytesRead;
sb=sb.append("\n Total bytes Read:"+totalRead);
Log.e("--",sb.toString());
/* if (this.length > 0) {
Long[] progress = new Long[5];
progress[0] = (long) ((double) totalRead / (double) this.length * 100.0);
publishProgress(progress);
}*/
if (this.isCancelled()) {
if (conn != null)
conn.disconnect();
conn = null;
break;
}
}
Log.e("Download completed","success");
out.flush();
//Utils.putDownloadLogs(requestUrl,mimeType,length, downloadFileName,"Download is Successful",sb.toString(), context);
outStream.close();
buffer = null;
} catch (Exception e) {
TraceUtils.logException( e);
file_newsize = storedFileSizeInDB + totalRead;
if (totalFileSize == 0)
totalFileSize = length;
callback.onRequestInterrupted(file_newsize,totalFileSize);
StringWriter errors = new StringWriter();
e.printStackTrace(new PrintWriter(errors));
// Utils.putDownloadLogs(requestUrl,mimeType,length,downloadFileName,"failure---" + errors.toString(),sb.toString(), context);
throw e;
} finally {
if (outStream != null)
outStream.close();
outStream = null;
}
}

You can use default download manager to download the file because its very easy to implement and provide better features like respond to the internet connection , provide accessibility to add notification in status bar , by running the query on download manager object you can find the total bytes and remaining bytes so you can calculate the progress and after completion of download by tapping the notification one can perform the desired operation.
And also there are many libraries are available for to achieve this like
PRDOWNLOADER
FetchDownloader
This libraires provide you the feature of pause,download, resume download , tracking the progress and cancel download
Also you can customize it as per your need.

Here is the DownloadAndEncryptFileTask.class to download with encryption
public class DownloadAndEncryptFileTask extends AsyncTask<Void, Void, Void> {
private String mUrl;
private File mFile;
private Cipher mCipher;
InputStream inputStream;
FileOutputStream fileOutputStream;
CipherOutputStream cipherOutputStream;
public DownloadAndEncryptFileTask(String url, File file, Cipher cipher) {
if (url == null || url.isEmpty()) {
throw new IllegalArgumentException("You need to supply a url to a clear MP4 file to download and encrypt, or modify the code to use a local encrypted mp4");
}
mUrl = url;
mFile = file;
mCipher = cipher;
}
private void downloadAndEncrypt() throws Exception {
URL url = new URL(mUrl);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
if (mFile.length() > 0) {
connection.setRequestProperty("Range", "bytes=" + mFile.length() + "-");
}
connection.connect();
Log.e("length", mFile.length() + "");
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
throw new IOException("server error: " + connection.getResponseCode() + ", " + connection.getResponseMessage());
}
inputStream = connection.getInputStream();
if (mFile.length() > 0) {
//connection.connect();
fileOutputStream = new FileOutputStream(mFile, true);
} else {
fileOutputStream = new FileOutputStream(mFile);
}
CipherOutputStream cipherOutputStream = new CipherOutputStream(fileOutputStream, mCipher);
byte buffer[] = new byte[1024 * 1024];
int bytesRead;
while ((bytesRead = inputStream.read(buffer)) != -1) {
Log.d(getClass().getCanonicalName(), "reading from http...");
cipherOutputStream.write(buffer, 0, bytesRead);
}
inputStream.close();
cipherOutputStream.close();
connection.disconnect();
}
#Override
protected Void doInBackground(Void... params) {
try {
downloadAndEncrypt();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void aVoid) {
Log.d(getClass().getCanonicalName(), "done");
}
}
Call this class
new DownloadAndEncryptFileTask(
myFeedsModel.getVideo().getVideo360(),
new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS), myFeedsModel.getFile_name()),
OBJECT OF YOUR CIPHER

Android download even if does not exist

try {
URL url = new URL("http://URL/Dragonfly.db");
HttpURLConnection c = (HttpURLConnection) url.openConnection();
c.setRequestMethod("GET");
c.setDoOutput(true);
c.connect();
String[] path = url.getPath().split("/");
String _file = path[path.length - 1];
int lengthOfFile = c.getContentLength();
if(lengthOfFile > 0){ // Copy file if Length > 0
String PATH = db.DB_PATH; ;//Environment.getExternalStorageDirectory()+
Log.v("", "PATH: " + PATH);
File file = new File(PATH);
file.mkdirs();
String fileName = "Dragonfly.db";
File outputFile = new File(file , fileName);
FileOutputStream fos = new FileOutputStream(outputFile);
InputStream is = c.getInputStream();
byte[] buffer = new byte[1024];
int len1 = 0;
while ((len1 = is.read(buffer)) != -1) {
fos.write(buffer, 0, len1);
}
fos.close();
is.close();
}else{
TestAdapter mDbHelper = new TestAdapter(getBaseContext());
mDbHelper.createDatabase();
}
} catch (IOException e) {
e.printStackTrace();
}
I use this code to update database, downloading a new one. but if i dont have a file on server, it replace the database i have for a new empty one (0bytes).
How can i download the file just if it exist on server?

Try to do a status response check:
int responseCode = c.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
{
// update database replacing the old one with the new one
} else {
// continue to use old database
}

Save image from url to sdcard

I am saving image from url to sdcard. But image size is 0 in sdcard. Image is created in sdcard but now retrieve data from url and save. so it is giving me 0 size.
try
{
URL url = new URL("http://api.androidhive.info/images/sample.jpg");
InputStream input = url.openStream();
try {
//The sdcard directory e.g. '/sdcard' can be used directly, or
//more safely abstracted with getExternalStorageDirectory()
File storagePath = Environment.getExternalStorageDirectory();
OutputStream output = new FileOutputStream (new File(storagePath,username+".png"));
try {
byte[] buffer = new byte[2048];
int bytesRead = 0;
while ((bytesRead = input.read(buffer, 0, buffer.length)) >= 0) {
output.write(buffer, 0, bytesRead);
}
} finally {
output.close();
}
} finally {
input.close();
}
} catch(Exception e)
{
System.out.println("error in sd card "+e.toString());
}

Try this code.It works...
You should have permission of internet and write external storage.
try
{
URL url = new URL("Enter the URL to be downloaded");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.connect();
File SDCardRoot = Environment.getExternalStorageDirectory().getAbsoluteFile();
String filename="downloadedFile.png";
Log.i("Local filename:",""+filename);
File file = new File(SDCardRoot,filename);
if(file.createNewFile())
{
file.createNewFile();
}
FileOutputStream fileOutput = new FileOutputStream(file);
InputStream inputStream = urlConnection.getInputStream();
int totalSize = urlConnection.getContentLength();
int downloadedSize = 0;
byte[] buffer = new byte[1024];
int bufferLength = 0;
while ( (bufferLength = inputStream.read(buffer)) > 0 )
{
fileOutput.write(buffer, 0, bufferLength);
downloadedSize += bufferLength;
Log.i("Progress:","downloadedSize:"+downloadedSize+"totalSize:"+ totalSize) ;
}
fileOutput.close();
if(downloadedSize==totalSize) filepath=file.getPath();
}
catch (MalformedURLException e)
{
e.printStackTrace();
}
catch (IOException e)
{
filepath=null;
e.printStackTrace();
}
Log.i("filepath:"," "+filepath) ;
return filepath;

Try this, this may late but it will help someone.
private class ImageDownloadAndSave extends AsyncTask<String, Void, Bitmap>
{
#Override
protected Bitmap doInBackground(String... arg0)
{
downloadImagesToSdCard("","");
return null;
}
private void downloadImagesToSdCard(String downloadUrl,String imageName)
{
try
{
URL url = new URL(img_URL);
/* making a directory in sdcard */
String sdCard=Environment.getExternalStorageDirectory().toString();
File myDir = new File(sdCard,"test.jpg");
/* if specified not exist create new */
if(!myDir.exists())
{
myDir.mkdir();
Log.v("", "inside mkdir");
}
/* checks the file and if it already exist delete */
String fname = imageName;
File file = new File (myDir, fname);
if (file.exists ())
file.delete ();
/* Open a connection */
URLConnection ucon = url.openConnection();
InputStream inputStream = null;
HttpURLConnection httpConn = (HttpURLConnection)ucon;
httpConn.setRequestMethod("GET");
httpConn.connect();
if (httpConn.getResponseCode() == HttpURLConnection.HTTP_OK)
{
inputStream = httpConn.getInputStream();
}
FileOutputStream fos = new FileOutputStream(file);
int totalSize = httpConn.getContentLength();
int downloadedSize = 0;
byte[] buffer = new byte[1024];
int bufferLength = 0;
while ( (bufferLength = inputStream.read(buffer)) >0 )
{
fos.write(buffer, 0, bufferLength);
downloadedSize += bufferLength;
Log.i("Progress:","downloadedSize:"+downloadedSize+"totalSize:"+ totalSize) ;
}
fos.close();
Log.d("test", "Image Saved in sdcard..");
}
catch(IOException io)
{
io.printStackTrace();
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
Declare your network operations in AsyncTask as it will load it as a background task. Don't load network operation on main thread. After this either in button click or in content view call this class like
new ImageDownloadAndSave().execute("");
And don't forget to add the nework permission as:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.INTERNET" />
Hope this will help :-)

Convert a BufferedInputStream to a File

I am loading a image from the web to the local android phone. The code that I have for writing to a file is as follows
BufferedInputStream bisMBImage=null;
InputStream isImage = null;
URL urlImage = null;
URLConnection urlImageCon = null;
try
{
urlImage = new URL(imageURL); //you can write here any link
urlImageCon = urlImage.openConnection();
isImage = urlImageCon.getInputStream();
bisMBImage = new BufferedInputStream(isImage);
int dotPos = imageURL.lastIndexOf(".");
if (dotPos > 0 )
{
imageExt = imageURL.substring(dotPos,imageURL.length());
}
imageFileName = PATH + "t1" + imageExt;
File file = new File(imageFileName);
if (file.exists())
{
file.delete();
Log.d("FD",imageFileName + " deleted");
}
ByteArrayBuffer baf = new ByteArrayBuffer(255);
Log.d("IMAGEWRITE", "Start to write image to Disk");
int current = 0;
try
{
while ((current = bisMBImage.read()) != -1)
{
baf.append((byte) current);
}
FileOutputStream fos = new FileOutputStream(file);
fos.write(baf.toByteArray());
fos.close();
Log.d("IMAGEWRITE", "Image write to Disk done");
}
catch (IOException e)
{
e.printStackTrace();
}
isImage.close();
}
catch (IOException e)
{
Log.d("DownloadImage", "Error: " + e);
}
finally
{
isImage = null;
urlImageCon = null;
urlImage = null;
}
For some reason the whole writing to a file takes 1 minute. Is there a way I can optimize this ?

Your buffer is very small: 255 bytes. You could make it 1024 times bigger (255 kilobytes). This is an acceptable size and this would certainly speed up the thing.
Also, this is very slow as it reads the bytes one by one:
while ((current = bisMBImage.read()) != -1) {
baf.append((byte) current);
}
You should try using the array version of read() instead: read(byte[] buffer, int offset, int byteCount) with an array as large as what I have described above.

You should use the Android HttpClient for file fetching over the java URL Connection. Also your Buffer is very small.
Try this snipped:
FileOutputStream f = new FileOutputStream(new File(root,"yourfile.dat"));
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet request = new HttpGet(urlString);
HttpResponse response = httpClient.execute(request);
InputStream is = response.getEntity().getContent();
byte[] buffer = new byte[1024];
int len1 = 0;
while ( (len1 = is.read(buffer)) > 0 ) {
f.write(buffer,0, len1);
}
f.close();

Download image(SSL) and store it on SDcard in Android?

I need to download a single image at time from the Internet and then save it on the SD card. How do I do it? I have made an attempt, but when I try to view that downloaded image, it shows the message, "No Preview Available". Please see my code below:
public class ImgDownloader {
private static final int IO_BUFFER_SIZE = 4 * 1024;
public static final byte[] downloadImage(String imgURL) {
byte[] data = null;
try {
Log.v("Down", "1");
InputStream in = null;
BufferedOutputStream out = null;
in = new BufferedInputStream(new URL(imgURL).openStream(), 8 * 1024);
Log.v("Down", "2");
final ByteArrayOutputStream dataStream = new ByteArrayOutputStream();
out = new BufferedOutputStream(dataStream, IO_BUFFER_SIZE);
copy(in, out);
out.flush();
Log.v("Down", "3");
data = dataStream.toByteArray();
// bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
Log.v("Down", "4");
} catch (Exception ex) {
ex.printStackTrace();
// System.out.println("Exception in Image Downloader .."
// +ex.getMessage());
}
return data;
}
private static void copy(InputStream in, OutputStream out)
throws IOException {
byte[] b = new byte[IO_BUFFER_SIZE];
int read;
while ((read = in.read(b)) != -1) {
out.write(b, 0, read);
}
}
}
Note:
i have download the image from the SSL connection.
Any ideas? Thanks in advance.

You can try something like
try{
URL url = new URL(downloadUrl); //you can write here any link
File file = new File(absolutePath); //Something like ("/sdcard/file.mp3")
//Create parent directory if it doesn't exists
if(!new File(file.getParent()).exists())
{
System.out.println("Path is created " + new File(file.getParent()).mkdirs());
}
file = new File(absolutePath); //Something like ("/sdcard/file.mp3")
file.createNewFile();
/* Open a connection to that URL. */
URLConnection ucon = url.openConnection();
/*
* Define InputStreams to read from the URLConnection.
*/
InputStream is = ucon.getInputStream();
/*
* Read bytes to the Buffer until there is nothing more to read(-1).
*/
FileOutputStream fos = new FileOutputStream(file);
int size = 1024*1024;
byte[] buf = new byte[size];
int byteRead;
while (((byteRead = is.read(buf)) != -1)) {
fos.write(buf, 0, byteRead);
bytesDownloaded += byteRead;
}
/* Convert the Bytes read to a String. */
fos.close();
}catch(IOException io)
{
networkException = true;
continueRestore = false;
}
catch(Exception e)
{
continueRestore = false;
e.printStackTrace();
}
Make the appropriate changes according to your requirement. I use the same code for downloading files from internet and saving it to SDCard.
Hope it helps !!