/*
** HTUU.CLASS
**
** ACKNOWLEDGEMENT:
** Main code is taken from the HTUU.C distribution, and was originally
** written by Mark Riordan (riordanmr@clvax1.cl.msu.edu)
** and Ari Luotonen (luotonen@dxcern.cern.ch).
**
** AUTHORS:
** IG Ian Goh ian.goh@jhu.edu
**
** HISTORY:
** Converted HTUU.C "HTUU_encode" function into Java (1.0.2): IG 13 July 1996
** -------------------------------------------------------------
** File contains a routine to convert a buffer
** of bytes to RFC 1113 printable encoding format.
**
** This technique is similar to the familiar Unix uuencode
** format in that it maps 6 binary bits to one ASCII
** character (or more aptly, 3 binary bytes to 4 ASCII
** characters). However, RFC 1113 does not use the same
** mapping to printable characters as uuencode.
**
** Mark Riordan 12 August 1990 and 17 Feb 1991.
** This code is hereby placed in the public domain.
** -------------------------------------------------------------
**
**
*/
package key.util;
public class HTUU {
static String version = "HTUU Class v1.0 7/13/96";
// the Base64 printable encoding characters
static char[] ENC = {
'A','B','C','D','E','F','G','H','I','J','K','L','M',
'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
'a','b','c','d','e','f','g','h','i','j','k','l','m',
'n','o','p','q','r','s','t','u','v','w','x','y','z',
'0','1','2','3','4','5','6','7','8','9','+','/'
};
// function encode takes the "username:password" string and
// converts it into the printable encoding format
public static String encode(String string) {
int i, j;
byte[] byte_array = new byte[3];
StringBuffer buf_coded = new StringBuffer();
// get length of input string
int nbytes = string.length();
for (i = 0; i < nbytes; i+= 3) {
// check to make sure we don't run off the end of input string
if (i + 3 < nbytes)
j = i + 3;
else
j = nbytes;
string.getBytes(i, j, byte_array, 0); // get bytes i..j
if (j - i == 1) {
// missing last two bytes
byte_array[1] = 0;
byte_array[2] = 0;
}
if (j - i == 2) {
// missing last byte
byte_array[2] = 0;
}
// convert the three bytes into four Base64 characters
// and append to the buf_coded string buffer
buf_coded.append(ENC[byte_array[0] >> 2]);
buf_coded.append(ENC[((byte_array[0] << 4) & 060) | ((byte_array[1] >> 4) & 017)]);
buf_coded.append(ENC[((byte_array[1] << 2) & 074) | ((byte_array[2] >> 6) & 03)]);
buf_coded.append(ENC[byte_array[2] & 077]);
} // end for loop
// If nbytes was not a multiple of 3, then we have encoded too
// many characters. Adjust appropriately.
int buf_length = buf_coded.length();
if (i == nbytes+1) {
/* There were only 2 bytes in that last group */
buf_coded.setCharAt(buf_length - 1, '=');
} else if (i == nbytes+2) {
/* There was only 1 byte in that last group */
buf_coded.setCharAt(buf_length - 1, '=');
buf_coded.setCharAt(buf_length - 2, '=');
}
// return the Base64 encoded string
return buf_coded.toString();
} // end String encode (String)
} // end Class HTUU
