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Name the images that i get from a web site in Java

I am scraping a web site and as a last part, I get their product images to the folder. I want to name these images like (product_id + numberOfImages) I mean if product has a 2 images, there will be 2 png like (productId_1) (productId_2).
I have productId and also images there is no problem. I just want to know how to name it as I want. Here is my code.
for(Element imageElement : imageElements){
String strImageURL = imageElement.attr("src");
String strImageName =product_id + "_" + ??;
try {
URL urlImage = new URL(strImageURL);
InputStream in = urlImage.openStream();
byte[] buffer = new byte[4096];
int n = -1;
OutputStream os = new FileOutputStream( IMAGE_DESTINATION_FOLDER + "/" + strImageName );
while ( (n = in.read(buffer)) != -1 ){
os.write(buffer, 0, n);
}
//close the stream
os.close();
} catch (IOException e) {
System.out.println("sponsored product");
}
// for loop images
}

I assume you are asking what to write instead of the ?? in the code in your question. Just create a counter variable.
int counter = 0;
for(Element imageElement : imageElements){
String strImageURL = imageElement.attr("src");
String strImageName = product_id + "_" + (++counter);
try {
URL urlImage = new URL(strImageURL);
InputStream in = urlImage.openStream();
byte[] buffer = new byte[4096];
int n = -1;
OutputStream os = new FileOutputStream( IMAGE_DESTINATION_FOLDER + "/" + strImageName );
while ( (n = in.read(buffer)) != -1 ){
os.write(buffer, 0, n);
}
//close the stream
os.close();
} catch (IOException e) {
System.out.println("sponsored product");
}
// for loop images
}

multi-pag tif to several jpeg files (java)

Hello I was able to convert a tif file to jpeg with the following code that I got from
https://stackoverflow.com/questions/15429011/how-to-convert-tiff-to-jpeg-png-in-java#=
String inPath = "./tifTest/113873996.002.tif";
String otPath = "./tifTest/113873996.002-0.jpeg";
BufferedInputStream input = null;
BufferedOutputStream output = null;
try {
input = new BufferedInputStream(new FileInputStream(inPath), DEFAULT_BUFFER_SIZE);
output = new BufferedOutputStream(new FileOutputStream(otPath), DEFAULT_BUFFER_SIZE);
byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
int length;
while ((length = input.read(buffer)) > 0) {
output.write(buffer, 0, length);
}
} catch (FileNotFoundException ex) {
Logger.getLogger(TifToJpeg.class.getName()).log(Level.SEVERE, null, ex);
} catch (IOException ex) {
Logger.getLogger(TifToJpeg.class.getName()).log(Level.SEVERE, null, ex);
} finally {
try {
output.flush();
output.close();
input.close();
} catch (IOException e) {
e.printStackTrace();
}
}
This only works with one-page tif file, and when I use it with a multi-page tif, it only saves the first page.
How can I modified this to save a mymultipagetif.tif into:
mymultipagetif-0.jpeg
mymultipagetif-1.jpeg
mymultipagetif-2.jpeg
Thanks!

This will takes a multi-page TIFF file (in the SeekableStream), extract the pages in the pages array ("1", "3", "4" for example) and write them into a single multi-page tiff into the file outTIffFileName. Modify as desired.
private String _ExtractListOfPages (SeekableStream ss, String outTiffFileName, String[] pages){
// pageNums is a String array of 0-based page numbers.
try {
TIFFDirectory td = new TIFFDirectory(ss, 0);
if (debugOn) {
System.out.println("Directory has " + Integer.toString(td.getNumEntries()) + " entries");
System.out.println("Getting TIFFFields");
System.out.println("X resolution = " + Float.toString(td.getFieldAsFloat(TIFFImageDecoder.TIFF_X_RESOLUTION)));
System.out.println("Y resolution = " + Float.toString(td.getFieldAsFloat(TIFFImageDecoder.TIFF_Y_RESOLUTION)));
System.out.println("Resolution unit = " + Long.toString(td.getFieldAsLong(TIFFImageDecoder.TIFF_RESOLUTION_UNIT)));
}
ImageDecoder decodedImage = ImageCodec.createImageDecoder("tiff", ss, null);
int count = decodedImage.getNumPages();
if (debugOn) { System.out.println("Input image has " + count + " page(s)"); }
TIFFEncodeParam param = new TIFFEncodeParam();
TIFFField tf = td.getField(259); // Compression as specified in the input file
param.setCompression(tf.getAsInt(0)); // Set the compression of the output to be the same.
param.setLittleEndian(false); // Intel
param.setExtraFields(td.getFields());
FileOutputStream fOut = new FileOutputStream(outTiffFileName);
Vector<RenderedImage> vector = new Vector<RenderedImage>();
RenderedImage page0 = decodedImage.decodeAsRenderedImage(Integer.parseInt(pages[0]));
BufferedImage img0 = new BufferedImage(page0.getColorModel(), (WritableRaster)page0.getData(), false, null);
int pgNum;
// Adding the extra pages starts with the second one on the list.
for (int i = 1; i < pages.length; i++ ) {
pgNum = Integer.parseInt(pages[i]);
if (debugOn) { System.out.println ("Page number " + pgNum); }
RenderedImage page = decodedImage.decodeAsRenderedImage(pgNum);
if (debugOn) { System.out.println ("Page is " + Integer.toString(page.getWidth()) + " pixels wide and "+ Integer.toString(page.getHeight()) + " pixels high."); }
if (debugOn) { System.out.println("Adding page " + pages[i] + " to vector"); }
vector.add(page);
}
param.setExtraImages(vector.iterator());
ImageEncoder encoder = ImageCodec.createImageEncoder("tiff", fOut, param);
if (debugOn) { System.out.println("Encoding page " + pages[0]); }
encoder.encode(decodedImage.decodeAsRenderedImage(Integer.parseInt(pages[0])));
fOut.close();
} catch (Exception e) {
System.out.println(e.toString());
return("Not OK " + e.getMessage());
}
return ("OK");
}

Downloading images overwrites the previous one

void downloadFile(){
try {
Bundle bundle = getIntent().getExtras();
String[] imageUrls = bundle.getStringArray(Extra.IMAGES);
// Log.v(imageUrls, "Creating view...");
int pagerPosition = bundle.getInt(Extra.IMAGE_POSITION, 0);
URL url = new URL(imageUrls[pagerPosition]);
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
//connect
urlConnection.connect();
//set the path where we want to save the file
File SDCardRoot = Environment.getExternalStorageDirectory();
//create a new file, to save the downloaded file
File file = new File(SDCardRoot,"image.png");
FileOutputStream fileOutput = new FileOutputStream(file);
//Stream used for reading the data from the internet
InputStream inputStream = urlConnection.getInputStream();
//this is the total size of the file which we are downloading
totalSize = urlConnection.getContentLength();
runOnUiThread(new Runnable() {
public void run() {
pb.setMax(totalSize);
}
});
//create a buffer...
byte[] buffer = new byte[1024];
int bufferLength = 0;
while ( (bufferLength = inputStream.read(buffer)) > 0 ) {
fileOutput.write(buffer, 0, bufferLength);
downloadedSize += bufferLength;
// update the progressbar //
runOnUiThread(new Runnable() {
public void run() {
pb.setProgress(downloadedSize);
float per = ((float)downloadedSize/totalSize) * 100;
cur_val.setText("Downloaded " + downloadedSize + "KB / " + totalSize + "KB (" + (int)per + "%)" );
}
});
}
//close the output stream when complete //
fileOutput.close();
runOnUiThread(new Runnable() {
public void run() {
// pb.dismiss(); // if you want close it..
}
});
} catch (final MalformedURLException e) {
showError("Error : MalformedURLException " + e);
e.printStackTrace();
} catch (final IOException e) {
showError("Error : IOException " + e);
e.printStackTrace();
}
catch (final Exception e) {
showError("Error : Please check your internet connection " + e);
}
}
Hi, I am using this function for downloading images from URLs which is working fine. But it overwrites the previously downloaded image..
File file = new File(SDCardRoot,"image.png");
How can I change the name with every new download in the above line.. its not accepting anything which is not a string.
Any help would be great.

Its because you always save images with same name image.png ,Change name using current datetime as
So change this
File file = new File(SDCardRoot,"image.png");
to
SimpleDateFormat formatter = new SimpleDateFormat("yyyy_MM_dd_HH_mm_ss");
Date now = new Date();
String fileName = "image" + formatter.format(now) + ".png";
File file = new File(SDCardRoot,fileName);
Edit
You may also use from Calendar as
Calendar calendar = Calendar.getInstance();
SimpleDateFormat formatter = new SimpleDateFormat("yyyy_MM_dd_HH_mm_ss");
String fileName = "image" + formatter.format(calendar.getTime()) + ".png";
File file = new File(SDCardRoot,fileName);

You can Give by this:
Calender calendar=Calender.getInstance();
String fileName = "image_" + calendar.getTimeInMillis() + ".png";
File file = new File(SDCardRoot,fileName);

How to correctly measure download speed with Java / Android

I'm trying to perform an AsyncTask class in my Android application that analyzes the network connection speed in for downloading and uploading. I'm working on the download portion now, but I'm not getting results I expect. I'm testing on a Wifi network that gets 15Mbps down/up speeds consistently, however, the results I'm getting from my application are more around barely 1Mbps. When I run the speed test apk on the device I'm testing on that gets around 3.5Mbps. The function works, just seems to be half the speed it should be. Should the following code produce accurate results?
try {
String DownloadUrl = "http://ipv4.download.thinkbroadband.com:8080/5MB.zip";
String fileName = "testfile.bin";
File dir = new File (context.getFilesDir() + "/temp/");
if(dir.exists()==false) {
dir.mkdirs();
}
URL url = new URL(DownloadUrl); //you can write here any link
File file = new File(context.getFilesDir() + "/temp/" + fileName);
long startTime = System.currentTimeMillis();
Log.d("DownloadManager", "download begining: " + startTime);
Log.d("DownloadManager", "download url:" + url);
Log.d("DownloadManager", "downloaded file name:" + fileName);
/* Open a connection to that URL. */
URLConnection ucon = url.openConnection();
//Define InputStreams to read from the URLConnection.
InputStream is = ucon.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
//Read bytes to the Buffer until there is nothing more to read(-1).
ByteArrayBuffer baf = new ByteArrayBuffer(1024);
int current = 0;
while ((current = bis.read()) != -1) {
baf.append((byte) current);
}
long endTime = System.currentTimeMillis(); //maybe
/* Convert the Bytes read to a String. */
FileOutputStream fos = new FileOutputStream(file);
fos.write(baf.toByteArray());
fos.flush();
fos.close();
File done = new File(context.getFilesDir() + "/temp/" + fileName);
Log.d("DownloadManager", "Location being searched: "+ context.getFilesDir() + "/temp/" + fileName);
double size = done.length();
if(done.exists()) {
done.delete();
}
Log.d("DownloadManager", "download ended: " + ((endTime - startTime) / 1000) + " secs");
double rate = (((size / 1024) / ((endTime - startTime) / 1000)) * 8);
rate = Math.round( rate * 100.0 ) / 100.0;
String ratevalue;
if(rate > 1000)
ratevalue = String.valueOf(rate / 1024).concat(" Mbps");
else
ratevalue = String.valueOf(rate).concat(" Kbps");
Log.d("DownloadManager", "download speed: "+ratevalue);
} catch (IOException e) {
Log.d("DownloadManager", "Error: " + e);
}
Example output
10-08 15:09:52.658: D/DownloadManager(13714): download ended: 70 secs
10-08 15:09:52.662: D/DownloadManager(13714): download speed: 585.14 Kbps
Thanks in advance for the help. If there is a better method, please let me know.

Following on my comments, here is an example of how to read several bytes from the stream
//Define InputStreams to read from the URLConnection.
InputStream is = ucon.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
//I usually use a ByteArrayOutputStream, as it is more common.
ByteArrayOutputStream baos = new ByteArrayOutputStream();
int red = 0;
// This size can be changed
byte[] buf = new byte[1024];
while ((red = bis.read(buf)) != -1) {
baos.write(buf, 0, red);
}
What this does is it reads into a byte[] buffer, and return the amount of read bytes. This is in turn written to the OutputStream, specifying the amount of bytes to write.
ByteArrayOutputStream also have a toByteArray that behaves similarly.
Alternatively, you can also write directly to the file, if you consider that the write to file operation is significantly faster than the read function :
// Simply start by defining the fileoutputstream
FileOutputStream fos = new FileOutputStream(file);
int red = 0;
// This size can be changed
byte[] buf = new byte[1024];
while ((red = bis.read(buf)) != -1) {
// And directly write to it.
fos.write(buf, 0, red);
}
long endTime = System.currentTimeMillis(); //maybe
// Flush after, as this may trigger a commit to disk.
fos.flush();
fos.close();
Moreover, if you really only care about the download speed, it is not mandatory to write to the file, or to anywhere, this would be sufficient :
long size = 0;
byte[] buf = new byte[1024];
while ((red = bis.read(buf)) != -1) {
size += red;
}

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!