How to read und hash files!?

Hi...
I'm facing some "InputStream" problems.
I want to hash files which is successful if files are < ~50MB. Here's my code...
long length = file.length();
InputStream in = new BufferedInputStream(new FileInputStream(file));
               byte[] message = new byte[(int)length];
                int offset = 0;
                  int numRead = 0;
                  while (offset < message.length
                         && (numRead=in.read(message, offset, message.length-offset)) >= 0)
                      offset += numRead;
MessageDigest md = MessageDigest.getInstance("MD5");
hash = md.digest(message);
* toHexString
**When I choose a file which is larger than 50 MB I get the following error:
Exception in thread "AWT-EventQueue-0" java.lang.OutOfMemoryError: Java heap space
I know what that error means and what could solve this but not how.

Have a look at the class java.security.DigestInputStream.

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Read and write one text file is not a problem, but what confusies me is how to read several text files at one time, in the meanwhile,
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I have reviewed some files and it is not helpful

Either with a 'for' loop like in the lib you have attached, or like this attached VI
that's it
Message Edited by devchander on 05-30-2006 05:11 AM
Attachments:
MULTIPLE READ.vi ‏44 KB

How to read multiple dat files.

Hello Everyone!
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import java.io.*;
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deepak_1your.com wrote:
hi,
If you want to read a file guarding yourself agianst exceptions....
check this article.... the code presented in this article might suit your needs...
[http://1your.com/fusion/infusions/articles/readarticle.php?article_id=17|http://1your.com/fusion/infusions/articles/readarticle.php?article_id=17]
And how does that help with a DataInputStream?

How to read an xml file from headers

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Edited by: 836719 on Feb 14, 2011 8:15 PM

836719 wrote:
ok i explain what i want to do maybe u can help me more,
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Edited by: user9003827 on Apr 13, 2010 3:42 AM

I think i have mixed it up :)
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}Edited by: Yannick.O on 13-Apr-2010 05:52

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