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download image but the size of image is not correct in kotlin

I found a amazing problem in downloading image.
The url of image is http://www.xbiquge.la/files/article/image/50/50353/50353s.jpg
I can open and save it in the chrome.but when I download it by the code,it fail.
I can't open it by the imageviewer.
Note:The size of wrong image is less than the right image file's.And other image of other website is ok.
I don't know what happen.Please help,Thanks advance
Following is my code
val imgUrl = "http://www.xbiquge.la/files/article/image/50/50353/50353s.jpg"
val conn = URL(imgUrl).openConnection()
val bytes = conn.getInputStream().readBytes()
File("D:\\test.jpg").writeBytes(bytes)
I also try to use java to download the image.it's also failure...
URL url = new URL("http://www.xbiquge.la/files/article/image/50/50353/50353s.jpg");
URLConnection connection=url.openConnection();
InputStream inputStream = connection.getInputStream();
BufferedInputStream bufferedInputStream = new BufferedInputStream(inputStream);
BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(new FileOutputStream(new File("d:\\download.jpg")));
int c;
byte[] temp = new byte[1024 * 2];
while ((c = bufferedInputStream.read(temp)) != -1) {
bufferedOutputStream.write(temp,0,c);
}
bufferedOutputStream.close();
inputStream.close();

It looks like the question answered here: Kotlin: How to save image from Internet to internal storage
I think you need to specify the format and compressiontype of how you want the image to be saved.

I found the right solution.
The reason is that the file is gzip file.
Must use following code to download it.
val openConnection = URL(url).openConnection()
//if the image file is gzip
val bytes = if (openConnection.contentEncoding == "gzip") {
GZIPInputStream(openConnection.getInputStream()).readBytes()
} else {
openConnection.getInputStream().readBytes()
}
val file = File("e:\\text.jpg")
file.writeBytes(bytes)

using Java to download file

I am trying to download a file from this url, but the code hang at getInputStream();
I type this url in the browser. the url is accessible
http://filehost.blob.core.windows.net/firmware/version.txt
What is the cause of it ?
URL url = new URL("http://filehost.blob.core.windows.net/firmware/version.txt");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.connect();
InputStream inputStream = urlConnection.getInputStream(); //hang at this line
int totalSize = urlConnection.getContentLength();

READING THE FILE CONTENT
SOLUTION
Use URL with Scanner.
CODE
URL url = new URL("http://filehost.blob.core.windows.net/firmware/version.txt");
Scanner s = new Scanner(url.openStream());
while (s.hasNextLine())
System.out.println(s.nextLine());
s.close();
OUTPUT
1.016
NOTE MalformedURLException and IOException must be thrown or handled.
DOWNLOADING THE FILE
SOLUTION
Use JAVA NIO.
CODE
URL website = new URL("http://filehost.blob.core.windows.net/firmware/version.txt");
ReadableByteChannel rbc = Channels.newChannel(website.openStream());
FileOutputStream fos = new FileOutputStream("C:/temp/version.txt");
fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
fos.close();
OUTPUT file has been created at c:\test\version.txt with 5 bytes size
NOTE MalformedURLException, FileNotFoundException and IOException must be thrown or handled.

I tried your code snippet and could not reproduce your problem - it does not hang for me. I think that your network (configuration) may have some problems and that your code hangs until some timeout occurs.

Downloading a file created in server using Java

I am trying to download a file from a given URL. The URL is not a direct file URL. When this URL is provided in browser manually, we get a prompt for download/save.
For example, http://www.my-domain.com/download/type/salary/format/excel
I have no issues in the URL which has the file name directly in the URL. In the above URL, based on the format and type, server generates the file.
In Java I am trying to download the file using the below code. The file is created, but the content is just the domain content and not the actual excel data.
URL url = new URL("http://www.my-domain.com/download/type/salary/format/excel");
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
float totalDataRead = 0;
BufferedInputStream in = new BufferedInputStream(connection.getInputStream());
FileOutputStream fos = new FileOutputStream("c:\\test.xls");
BufferedOutputStream bout = new BufferedOutputStream(fos, 1024);
byte[] data = new byte[1024];
int i = 0;
while ((i = in.read(data, 0, 1024)) >= 0) {
totalDataRead = totalDataRead + i;
bout.write(data, 0, i);
}
bout.close();
in.close();

The content is whatever the server sent for that URL. You can't do anything about that from the client end. If it contained Javascript for example it won't get executed.

When you want to solve a problem you have to use the adequate tools to get the thing done. The adequate tools can be found at poi.apache.org. Have a look at Apache POI.

Android copying large inputstream to file very slow

I have an app that is downloading a zip file and then copying this file to a temporary file on the sd card on the phone, but it is being very very slow.
InputStream in = new BufferedInputStream(url.openStream(), 1024);
File tempFile = File.createTempFile("arc", ".zip", targetDir); //target dir is a file
String tempFilePath = tempFile.getAbsolutePath();
OutputStream out = new BufferedOutputStream(new FileOutputStream(tempFile));
//copying file (in different void)
byte[] buffer = new byte[8192];
int len;
len = in.read(buffer);
enter code here
//it loops here for AGES
while (len >= 0) {
out.write(buffer, 0, len);
len = in.read(buffer);
}
in.close();
out.close();
My file is about 20MB, initially I had the buffer size of 1024, and changed it to 8192 thinking it may speed it up but it seemed to make no difference? I always finishes, and I get no errors it just takes ages!
I have searched to try and find a solution but I'm not coming up with anything so I may be going about this totally the wrong way?
Can anyone see what I'm doing wrong?
Bex

Donot increase buffer size. That may cause your application MemoryOutOfBoundsException.
There are varous factors for which your download will be slow. Weak internet connection, Weak file transfer and receiveing mode is also responsible. It also depend on capacity of device. Check whether you are using following code to create inputstream
URL u = new URL("enter url url here");
HttpURLConnection c = (HttpURLConnection) u.openConnection();
c.setRequestMethod("GET");
c.setDoOutput(true);
c.connect();
InputStream in = c.getInputStream();
Thanks
Deepak

URL Connection (FTP) in Java - Simple Question

I have a simple question. I'm trying to upload a file to my ftp server in Java.
I have a file on my computer, and I want to make a copy of that file and upload it. I tried manually writing each byte of the file to the output stream, but that doesn't work for complicated files, like zip files or pdf files.
File file = some file on my computer;
String name = file.getName();
URL url = new URL("ftp://user:password#domain.com/" + name +";type=i");
URLConnection urlc = url.openConnection();
OutputStream os = urlc.getOutputStream();
//then what do I do?
Just for kicks, here is what I tried to do:
OutputStream os = urlc.getOutputStream();
BufferedReader br = new BufferedReader(new FileReader(file));
String line = br.readLine();
while(line != null && (!line.equals(""))) {
os.write(line.getBytes());
os.write("\n".getBytes());
line = br.readLine();
}
os.close();
For example, when I do this with a pdf and then try and open the pdf that I run with this program, it says an error occurred when trying to open the pdf. I'm guessing because I am writing a "\n" to the file? How do I copy the file without doing this?

Do not use any of the Reader or Writer classes when you're trying to copy the byte-for-byte exact contents of a binary file. Use these only for plain text! Instead, use the InputStream and OutputStream classes; they do not interpret the data at all, while the Reader and Writer classes interpret the data as characters. For example
OutputStream os = urlc.getOutputStream();
FileInputStreamReader fis = new FileInputStream(file);
byte[] buffer = new byte[1000];
int count = 0;
while((count = fis.read(buffer)) > 0) {
os.write(buffer, 0, count);
}
Whether your URLConnection usage is correct here, I don't know; using Apache Commons FTP (as suggested elsewhere) would be an excellent idea. Regardless, this would be the way to read the file.

Use a BufferedInputStream to read and BufferedOutputStream to write. Take a look at this post: http://www.ajaxapp.com/2009/02/21/a-simple-java-ftp-connection-file-download-and-upload/
InputStream is = new FileInputStream(localfilename);
BufferedInputStream bis = new BufferedInputStream(is);
OutputStream os =m_client.getOutputStream();
BufferedOutputStream bos = new BufferedOutputStream(os);
byte[] buffer = new byte[1024];
int readCount;
while( (readCount = bis.read(buffer)) > 0) {
bos.write(buffer, 0, readCount);
}
bos.close();

FTP usually opens another connection for data transfer.
So I am not convinced that this approach with URLConnection is going
to work.
I highly recommend that you use specialized ftp client. Apache commons
may have one.
Check this out
http://commons.apache.org/net/api/org/apache/commons/net/ftp/FTPClient.html