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Android several images downloaded from server are being corrupted

I'm using a function to download an image from a server to the internal memory of my android device, the function is :
private void downloadFile(String myurl, String name) {
// TODO Auto-generated method stub
int count=0;
try {
URL url = new URL(myurl);
URLConnection conexion = url.openConnection();
conexion.connect();
lenghtOfFile = conexion.getContentLength();
Log.d("ANDRO_ASYNC", "Lenght of file: " + lenghtOfFile);
InputStream input = new BufferedInputStream(url.openStream());
OutputStream output = new FileOutputStream(Environment.getExternalStorageDirectory().getAbsolutePath() + "/test library/"+name.replace(" ","")+".png");
byte data[] = new byte[1024];
total = 0;
while ((count = input.read(data)) != -1) {
total += count;
publishProgress(""+(int)((total*100)/lenghtOfFile));
output.write(data, 0, count);
}
output.flush();
output.close();
input.close();
} catch (Exception e) {a=e.toString();}
}
I have 22 images on the server, the problem is that some images are being downloaded as corrupted files, any help please ?

Request Method GET returns wrong content length

Hi i am using an HttpURLConnection that gets a txt file's content and i want to know the size of that file and i use the content length Method but it returns wrong value for example in this code the file's size is 17509 but it returns 5147 ?
so Any Help?
Thanks so much in advance :).
new Thread() {
#Override
public void run() {
String path = parser.getValue(e, "txt");
URL u = null;
try {
u = new URL(path);
HttpURLConnection c = (HttpURLConnection) u
.openConnection();
c.setRequestMethod("GET");
c.connect();
int lenghtOfFile = c.getContentLength();
InputStream in = c.getInputStream();
final ByteArrayOutputStream bo = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
long total = 0;
Log.i("p1",""+lenghtOfFile);
while ((count = in.read(buffer)) != -1) {
total += count;
Log.i("p2",""+total);
bo.write(buffer, 0, count);
}
bo.close();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (ProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}.start();

The content-length is a header set by the server. I would check to make sure that your server is returning the correct content-length. You can do that with cUrl:
curl -v http://path/to/file.txt
That should show you the headers that were sent and returned.

A quick workaround I can think of, is just ignoring the content-length and reading input stream until there's nothing left to read.
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream(8192);
int read = inputStream.read();
while (read != -1) {
byteArrayOutputStream.write((byte) read);
read = inputStream.read();
}
byteArrayOutputStream.flush();
buf = byteArrayOutputStream.toByteArray();

How to write files to an SD Card from the internet?

An example would be a simple image.
I have tried so many things and it just refuses to work despite making a whole lot of sense.
What I've done so far is I'm able to grab 25 pictures and add them to
/sdcard/app name/sub/dir/filename.jpg
They all appear there according to the DDMS but they always have a filesize of 0.
I'm guessing it's probably because of my input stream?
Here's my function that handles the downloading and saving.
public void DownloadPages()
{
for (int fileC = 0; fileC < pageAmount; fileC++)
{
URL url;
String path = "/sdcard/Appname/sub/dir/";
File file = new File(path, fileC + ".jpg");
int size=0;
byte[] buffer=null;
try{
url = new URL("http://images.bluegartr.com/bucket/gallery/56ca6f9f2ef43ab7349c0e6511edb6d6.png");
InputStream in = url.openStream();
size = in.available();
buffer = new byte[size];
in.read(buffer);
in.close();
}catch(Exception e){
}
if (!new File(path).exists())
new File(path).mkdirs();
FileOutputStream out;
try{
out = new FileOutputStream(file);
out.write(buffer);
out.flush();
out.close();
}catch(Exception e){
}
}
}
It just keeps giving me 25 files in that directory but all of their file sizes are zero. I have no idea why. This is practically the same code I've used in a java program.
PS...
If you're gonna give me a solution... I've already tried code like this. It doesn't work.
try{
url = new URL(urlString);
in = new BufferedInputStream(url.openStream());
fout = new FileOutputStream(filename);
byte data[] = new byte[1024];
int count;
System.out.println("Now downloading File: " + filename.substring(0, filename.lastIndexOf(".")));
while ((count = in.read(data, 0, 1024)) != -1){
fout.write(data, 0, count);
}
}finally{
System.out.println("Download complete.");
if (in != null)
in.close();
if (fout != null)
fout.close();
}
}
Here's an image of what my directories look like
http://oi48.tinypic.com/2cpcprm.jpg

A bit change to your second option, try it as following way,
byte data[] = new byte[1024];
long total = 0;
int count;
while ( ( count = input.read(data)) != -1 )
{
total += count;
output.write( data,0,count );
}
This one is different in while statement while ((count = in.read(data, 0, 1024)) != -1)

Using Guava something like this should work:
String fileUrl = "xxx";
File file = null;
InputStream in;
FileOutputStream out;
try {
Uri url = new URI(fileUrl);
in = url.openStream();
out = new FileOutputStream(file)
ByteStreams.copy(in, out);
}
catch (IOException e) {
System.out.println(e.toString());
}
finally {
in.close();
out.flush();
out.close();
}

Android:"Unexpected end of stream" exception downloading large files

I am building an Android Application and I need to download a file from a url, which is 33 MB large.
Here the download task:
try {
int MAX_BUFFER_SIZE = 4096;
URL mUrl = new URL(params[0]);
HttpURLConnection connection = (HttpURLConnection) mUrl.openConnection();
connection.setRequestMethod("GET");
long length = connection.getContentLength(), downloaded = 0;
int read;
byte [] buffer = new byte[(((int)length) > MAX_BUFFER_SIZE) ? MAX_BUFFER_SIZE : (int)length];
String filename = getFilename(mUrl);
File file = new File (SDCARD_ROOT);
if (!file.exists() || !file.isDirectory()){
file.mkdir();
}
this.filename = filename;
file = new File (SDCARD_ROOT + this.filename);
FileOutputStream fos = new FileOutputStream (file);
//Start downloading
InputStream stream = connection.getInputStream();
while ((read=stream.read(buffer)) > -1){
fos.write(buffer, 0, read);
downloaded += read;
publishProgress((int) ((float) downloaded/length * 100));
}
fos.close();
return 1;
} catch (Exception e){
Log.e("REV-PARTS", "Revolver parts error in DownloadTask: " + e.getMessage());
return 2;
}
It works right with small files (1-15 MB), but it will return a "unexpected end of stream" exception with large files.

Setting a chunk size seemed to work for me.
connection.setChunkedStreamingMode(1048576);

For large files you need to set the connection time out manually by using the following code.
I have set the time out to 3 minutes
connection.setConnectTimeout(180000);
connection.setReadTimeout(180000);

While you catch the exception, I try the method downContinue(). I can show my code:
private void downloadApk() {
thread1 = new Thread() {
public void run() {
File oFile = null;
try {
URL url = new URL(PQGLApplication.resrootURL + "apk/PQGLMap.apk");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
ReadableByteChannel channel =
Channels.newChannel(urlConnection.getInputStream());
oFile =
new File(Environment.getExternalStorageDirectory().getAbsolutePath()
+ "/" + "hy_ht_new/" + "test2" + ".apk");
oFile.setWritable(true);
oFile.setReadable(true);
if (oFile.exists()) {
oFile.delete();
}
FileOutputStream fos = new FileOutputStream(oFile);
fileSize = urlConnection.getContentLength();
ByteBuffer buffer = ByteBuffer.allocate(1024);
int noOfBytes = 0;
byte[] data = null;
sendApkMessage(0, 0);
while ((noOfBytes = channel.read(buffer)) > 0) {
data = new byte[noOfBytes];
System.arraycopy(buffer.array(), 0, data, 0, noOfBytes);
buffer.clear();
fos.write(data, 0, noOfBytes);
downLoadFileSize += noOfBytes;
sendApkMessage(1, downLoadFileSize);
}
fos.flush();
fos.close();
channel.close();
sendApkMessage(2, oFile.getAbsolutePath());
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
downContinue();
}
};
};
thread1.start();
}
private void downContinue() {
continueTime++;
try {
if (continueTime == 3) {
continueTime = 0;
sendApkMessage(4, 0);
Log.e("what is the continuetime", "continueTime" + continueTime);
} else {
URL url = new URL(PQGLApplication.resrootURL + "apk/PQGLMap.apk");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
File oFile =
new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/"
+ "hy_ht_new/" + "test2" + ".apk");
RandomAccessFile oSavedFile = new RandomAccessFile(oFile, "rw");
FileOutputStream fos = new FileOutputStream(oFile);
ReadableByteChannel channel = Channels.newChannel(urlConnection.getInputStream());
// oSavedFile.seek(nPos);
ByteBuffer buffer = ByteBuffer.allocate(1024);
byte[] data = null;
int temp = 0;
sendApkMessage(3, oFile.getAbsolutePath());
while ((temp = channel.read(buffer)) > 0) {
data = new byte[temp];
System.arraycopy(buffer.array(), 0, data, 0, temp);
buffer.clear();
fos.write(data, 0, temp);
}
fos.flush();
fos.close();
oSavedFile.close();
sendApkMessage(2, oFile.getAbsolutePath());
continueTime = 0;
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
Log.e("what is the exception", e.toString() + continueTime);
downContinue();
}
}
This downContinue method is used to solve this problem. At least, the file is downloaded successfully!

Android download binary file problems

I am having problems downloading a binary file (video) in my app from the internet. In Quicktime, If I download it directly it works fine but through my app somehow it get's messed up (even though they look exactly the same in a text editor). Here is a example:
URL u = new URL("http://www.path.to/a.mp4?video");
HttpURLConnection c = (HttpURLConnection) u.openConnection();
c.setRequestMethod("GET");
c.setDoOutput(true);
c.connect();
FileOutputStream f = new FileOutputStream(new File(root,"Video.mp4"));
InputStream in = c.getInputStream();
byte[] buffer = new byte[1024];
int len1 = 0;
while ( (len1 = in.read(buffer)) > 0 ) {
f.write(buffer);
}
f.close();

I don't know if it's the only problem, but you've got a classic Java glitch in there: You're not counting on the fact that read() is always allowed to return fewer bytes than you ask for. Thus, your read could get less than 1024 bytes but your write always writes out exactly 1024 bytes possibly including bytes from the previous loop iteration.
Correct with:
while ( (len1 = in.read(buffer)) > 0 ) {
f.write(buffer,0, len1);
}
Perhaps the higher latency networking or smaller packet sizes of 3G on Android are exacerbating the effect?

new DefaultHttpClient().execute(new HttpGet("http://www.path.to/a.mp4?video"))
.getEntity().writeTo(
new FileOutputStream(new File(root,"Video.mp4")));

One problem is your reading of the buffer. If every read of the input stream is not an exact multiple of 1024 you will copy bad data. Use:
byte[] buffer = new byte[1024];
int len1 = 0;
while ( (len1 = in.read(buffer)) != -1 ) {
f.write(buffer,0, len1);
}

public class download extends Activity {
private static String fileName = "file.3gp";
private static final String MY_URL = "Your download url goes here";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
try {
URL url = new URL(MY_URL);
HttpURLConnection c = (HttpURLConnection) url.openConnection();
c.setRequestMethod("GET");
c.setDoOutput(true);
c.connect();
String PATH = Environment.getExternalStorageDirectory()
+ "/download/";
Log.d("Abhan", "PATH: " + PATH);
File file = new File(PATH);
if(!file.exists()) {
file.mkdirs();
}
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.flush();
fos.close();
is.close();
} catch (IOException e) {
Log.e("Abhan", "Error: " + e);
}
Log.i("Abhan", "Check Your File.");
}
}

I fixed the code based on previous feedbacks on this thread. I tested using eclipse and multiple large files. It is working fine. Just have to copy and paste this to your environment and change the http path and the location which you would like the file to be downloaded to.
try {
//this is the file you want to download from the remote server
String path ="http://localhost:8080/somefile.zip";
//this is the name of the local file you will create
String targetFileName
boolean eof = false;
URL u = new URL(path);
HttpURLConnection c = (HttpURLConnection) u.openConnection();
c.setRequestMethod("GET");
c.setDoOutput(true);
c.connect();
FileOutputStream f = new FileOutputStream(new File("c:\\junk\\"+targetFileName));
InputStream in = c.getInputStream();
byte[] buffer = new byte[1024];
int len1 = 0;
while ( (len1 = in.read(buffer)) > 0 ) {
f.write(buffer,0, len1);
}
f.close();
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Good luck
Alireza Aghamohammadi

Just use apache's copy method (Apache Commons IO) - the advantage of using Java!
IOUtils.copy(is, os);
Do not forget to close the streams in a finally block:
try{
...
} finally {
IOUtils.closeQuietly(is);
IOUtils.closeQuietly(os);
}