// Base64Encoder.java
// $Id: Base64Encoder.java,v 1.1 2002/07/11 12:00:11 ohitz Exp $
// (c) COPYRIGHT MIT and INRIA, 1996.
// Please first read the full copyright statement in file COPYRIGHT.html
package iiuf.util;
import java.io.* ;
import java.math.*;
/**
* BASE64 encoder implementation.
* This object takes as parameter an input stream and an output stream. It
* encodes the input stream, using the BASE64 encoding rules, as defined
* in <a href="http://ds.internic.net/rfc/rfc1521.txt">MIME specification</a>
* and emit the resulting data to the output stream.
* @see iiuf.util.Base64Decoder
*/
public class Base64Encoder {
private static final int BUFFER_SIZE = 1024 ;
private static byte[] encoding = {
(byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D',
(byte) 'E', (byte) 'F', (byte) 'G', (byte) 'H',
(byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L',
(byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P',
(byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T',
(byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X',
(byte) 'Y', (byte) 'Z', (byte) 'a', (byte) 'b',
(byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f',
(byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j',
(byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n',
(byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r',
(byte) 's', (byte) 't', (byte) 'u', (byte) 'v',
(byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z',
(byte) '0', (byte) '1', (byte) '2', (byte) '3',
(byte) '4', (byte) '5', (byte) '6', (byte) '7',
(byte) '8', (byte) '9', (byte) '+', (byte) '/',
(byte) '='
};
InputStream in = null ;
OutputStream out = null ;
boolean stringp = false ;
private final int get1(byte buf[], int off) {
return (buf[off] & 0xfc) >> 2 ;
}
private final int get2(byte buf[], int off) {
return ((buf[off]&0x3) << 4) | ((buf[off+1]&0xf0) >>> 4) ;
}
private final int get3(byte buf[], int off) {
return ((buf[off+1] & 0x0f) << 2) | ((buf[off+2] & 0xc0) >>> 6) ;
}
private static final int get4(byte buf[], int off) {
return buf[off+2] & 0x3f ;
}
/**
* Process the data: encode the input stream to the output stream.
* This method runs through the input stream, encoding it to the output
* stream.
* @exception IOException If we weren't able to access the input stream or
* the output stream.
*/
public void process ()
throws IOException
{
byte buffer[] = new byte[BUFFER_SIZE] ;
int got = -1 ;
int off = 0 ;
int count = 0 ;
while ((got = in.read(buffer, off, BUFFER_SIZE-off)) > 0) {
if ( got >= 3 ) {
got += off;
off = 0;
while (off + 3 <= got) {
int c1 = get1(buffer,off) ;
int c2 = get2(buffer,off) ;
int c3 = get3(buffer,off) ;
int c4 = get4(buffer,off) ;
switch (count) {
case 73:
out.write(encoding[c1]);
out.write(encoding[c2]);
out.write(encoding[c3]);
out.write ('\n') ;
out.write(encoding[c4]) ;
count = 1 ;
break ;
case 74:
out.write(encoding[c1]);
out.write(encoding[c2]);
out.write ('\n') ;
out.write(encoding[c3]);
out.write(encoding[c4]) ;
count = 2 ;
break ;
case 75:
out.write(encoding[c1]);
out.write ('\n') ;
out.write(encoding[c2]);
out.write(encoding[c3]);
out.write(encoding[c4]) ;
count = 3 ;
break ;
case 76:
out.write('\n') ;
out.write(encoding[c1]);
out.write(encoding[c2]);
out.write(encoding[c3]);
out.write(encoding[c4]) ;
count = 4 ;
break ;
default:
out.write(encoding[c1]);
out.write(encoding[c2]);
out.write(encoding[c3]);
out.write(encoding[c4]) ;
count += 4 ;
break ;
}
off += 3 ;
}
// Copy remaining bytes to beginning of buffer:
for ( int i = 0 ; i < 3 ;i++)
buffer[i] = (i < got-off) ? buffer[off+i] : ((byte) 0) ;
off = got-off ;
} else {
// Total read amount is less then 3 bytes:
off += got;
}
}
// Manage the last bytes, from 0 to off:
switch (off) {
case 1:
out.write(encoding[get1(buffer, 0)]) ;
out.write(encoding[get2(buffer, 0)]) ;
out.write('=') ;
out.write('=') ;
break ;
case 2:
out.write(encoding[get1(buffer, 0)]);
out.write(encoding[get2(buffer, 0)]);
out.write(encoding[get3(buffer, 0)]);
out.write('=');
}
return ;
}
/**
* Encode the content of this encoder, as a string.
* This methods encode the String content, that was provided at creation
* time, following the BASE64 rules, as specified in the rfc1521.
* @return A String, reprenting the encoded content of the input String.
*/
public String processString () {
if ( ! stringp )
throw new RuntimeException (this.getClass().getName()
+ "[processString]"
+ "invalid call (not a String)");
try {
process() ;
} catch (IOException e) {
}
return ((ByteArrayOutputStream) out).toString() ;
}
/**
* Create a new Base64 encoder, to encode the given string.
* @param input The String to be encoded.
*/
public Base64Encoder (String input) {
byte bytes[] = input.getBytes();
this.stringp = true ;
this.in = new ByteArrayInputStream(bytes) ;
this.out = new ByteArrayOutputStream () ;
}
/**
* Create a new Base64 encoder, encoding input to output.
* @param in The input stream to be encoded.
* @param out The output stream, to write encoded data to.
*/
public Base64Encoder (InputStream in, OutputStream out) {
this.in = in ;
this.out = out ;
this.stringp = false ;
}
/**
* Create a new Base64 encoder, to encode the given byte array.
* @param input The Byte Array to be encoded.
*/
public Base64Encoder (byte bytes[]) {
this.stringp = true ;
this.in = new ByteArrayInputStream(bytes) ;
this.out = new ByteArrayOutputStream () ;
}
/**
* Create a new Base64 encoder, to encode the given BigInteger.
* @param input The BigInteger to be encoded.
*/
public Base64Encoder (BigInteger bint) {
this.stringp = true ;
this.in = new ByteArrayInputStream(bint.toByteArray()) ;
this.out = new ByteArrayOutputStream () ;
}
/**
* Testing the encoder.
* Run with one argument, prints the encoded version of it.
*/
public static void main (String args[]) {
if ( args.length != 1 ) {
System.out.println ("Base64Encoder <string>") ;
System.exit (0) ;
}
Base64Encoder b = new Base64Encoder (args[0]) ;
System.out.println ("["+b.processString()+"]") ;
// joe:eoj -> am9lOmVvag==
// 12345678:87654321 -> MTIzNDU2Nzg6ODc2NTQzMjE=
}
}