[Advanced-java] XOR of byte

[mailing_list_sg at yahoo.com (Kwan Hon Luen)]

Hi ,

I heard that when   A  XOR  B   =   C

then     C    XOR    B    =    A

I have the following code, can someone guide me on this ??

import com.Ostermiller.util.*;
import java.io.*;

public class test
{
    public static void main (String args[])
    {
  String str = "FIRST";
  String str2 = "SECOND";

  byte[] myByte = {};
  byte[] myByte2 = {};
  try
  {
   myByte = str.getBytes( "UTF8" );
   myByte2 = str2.getBytes( "UTF8" );
  }
  catch ( UnsupportedEncodingException e )
  {
  }

  MD5 myMD5 = new MD5();

  //String MD5_1 = myMD5.getHashString(myByte);
  byte[] MD5_1_byte = myMD5.getHash(myByte);
  //String MD5_2 = myMD5.getHashString(myByte2);
  byte[] MD5_2_byte = myMD5.getHash(myByte2);


//////   How do I do a XOR between  MD5_1_byte     and    MD5_2_byte  ??
/////    Assuming  ( MD5_1_byte )   XOR  ( MD5_2_byte )  =   myXORresult
/////    How do I do a XOR between  myXORresult   and  MD5_1_byte   to get
MD5_2_byte  ??


 }
}




----- Original Message -----
From: "H.J. Tsai" <hjtsai@xxxxxxxxxxxx>
To: <mailing_list_sg@xxxxxxxxx>
Sent: Friday, March 01, 2002 1:07 AM


>
> Look up the binary operators '^' and '&' and do something
> like the following
>
> byte[] b1 = ...
> byte[] b2 = ...
>
> for (int i=0; i<b1.length; i++) {
>      byte b = (byte) (b1[i] ^ b2[i]);
>      int  i = (b1[i] ^ b2[i]) & 0xff;
> }
>
> Regards
> HJ Tsai
>
>  >Hi ,
>  >How do I do a XOR between two byte[] arrays ?
>  >
>  >thks,
>  >Hon Luen


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