RE: base64 encoded content

[Dale Manny]

Holger:

I knew something had been said on this subject previously...I took note but
it is not impacting me yet.  See the attached note from Jason Robertson on
1/29/2001.  I didn't see any ack of someone handling his patch.

Dale




-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]
Sent: Thursday, February 08, 2001 9:25 AM
To: [EMAIL PROTECTED]
Subject: base64 encoded content




Hi,

I'm using the Base64 class to encode and decode binary data in xml files
and encountered some strange things I hope someone can explain.

If I'm encoding a byte array with a size of 33552 bytes I get an array of
the length 44736, which seems correct to me. Decoding it returns an array
with 33553 bytes - one more than the original byte array. This looks like a
bug, am I right? If I'm right, does anyone has fixed it already?

The second strange effect occurs while parsing the xml document with the
encoded data. The document looks like that:

     <content>/KJjndlkh/lhjnlkj...</content>

The SAX parser splits my content into three parts, invoking the
"characters" method three times. Am I doing something wrong?

Thanks for any idea!
Holger



---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]

--- Begin Message ---

The utils class Base64 has a bug in the decode method - the byte array
returned has the wrong length. This simple example shows the problem:

public class test
{
    public static void main( String args[] ) 
    {
        byte[] original = new byte[1];
        original[0] = 'A';
        
        byte[] encoded = org.apache.xerces.utils.Base64.encode( original );
        byte[] decoded = org.apache.xerces.utils.Base64.decode( encoded );
        
        if ( original.length != decoded.length )
        {
            System.out.println( "Sizes aren't the same!" );
            System.out.println( "Original: '" + new String( original ) + "'"
);
            System.out.println( "Decoded : '" + new String( decoded ) + "'"
);
        }
    }
}
 
The output is this:
 
     Sizes aren't the same!
     Original: 'A'
     Decoded : 'A   '
 
Note the extra spaces after the decoded value (actually zero-value bytes, I
think). The problem in the code is that no adjustment is made for padding
characters when the size of the output buffer is determined:
 
        decodedData      = new byte[ numberQuadruple*3 + 1 ];

Should be:
 
        decodedData      = new byte[ numberQuadruple*3 - numberPadCharacters
];
 
(where numberPadCharacters must be determined). 
 
Not really sure why the +1 is there on the current code, seems very C-ish in
that the code is assuming it's a string and is making room for the
null-terminating character.
 
Jason

--- End Message ---