Current File : //proc/thread-self/root/home/waritko/yacy/libbuild/WebCat-swf/src/pt/tumba/parser/swf/Base64.java
package pt.tumba.parser.swf;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.StringReader;
import java.io.StringWriter;
import java.io.Writer;
import java.util.HashMap;
/**
* Base64 encoding/decoding utilities
*
*@author unknown
*@created 15 de Setembro de 2002
*/
public class Base64 {
private static final Base64 _theInstance = new Base64();
private Base64() {
}
public static Base64 getInstance() {
return _theInstance;
}
public final static char[] charset =
{
'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', '+', '/'
};
public final static char paddingChar = '=';
protected static HashMap charLookup = new HashMap();
static {
//initialize the hashtable
for (int i = 0; i < charset.length; i++) {
charLookup.put(new Character(charset[i]),
new Integer(i));
}
}
/**
* Description of the Method
*
*@param in Description of the Parameter
*@param out Description of the Parameter
*@exception Exception Description of the Exception
*/
public static void decode(Reader in, OutputStream out)
throws Exception {
char[] chars = new char[4];
int[] sixbit = new int[4];
//--Process the input stream in 4-character chunks
while (true) {
int numread = 0;
while (numread < 4) {
int read = in.read();
if (read < 0) {
break;
}
//end of input
char aChar = (char) read;
if (Character.isWhitespace(aChar)) {
continue;
}
//skip w/s
chars[numread++] = aChar;
}
if (numread == 0) {
return;
}
//end of input
if (numread != 4) {
throw new Exception("Incomplete character quartet at end of Base64 input");
}
//--Convert chars to six-bit values
for (int i = 0; i < 4; i++) {
Integer value = (Integer) charLookup.get(new Character(chars[i]));
if (value == null) {
if (chars[i] != '=' || i < 2) {
throw new Exception("Invalid char ("
+ chars[i] + ") in Base64 data");
}
sixbit[i] = -1;
} else {
sixbit[i] = value.intValue();
}
}
//--Write first 6 bits and top 2 bits from second value
out.write((sixbit[0] << 2) + (sixbit[1] >> 4));
//System.out.println( (sixbit[0] << 2) + (sixbit[1] >> 4) );
//--Get bottom four bits of second value
int val = (sixbit[1] & 0xf) << 4;
if (sixbit[2] >= 0) {
//third value is valid
//--Add top four bits of third value
val += sixbit[2] >> 2;
out.write(val);
//System.out.println( val );
//--Get bottom two bits of third value
val = (sixbit[2] & 0x3) << 6;
if (sixbit[3] >= 0) {
//fourth value is valid
val += sixbit[3];
out.write(val);
//System.out.println( val );
}
}
}
}
/**
* Description of the Method
*
*@param base64 Description of the Parameter
*@return Description of the Return Value
*@exception Exception Description of the Exception
*/
public static byte[] decode(String base64)
throws Exception {
//if base64 is invalid
ByteArrayOutputStream out = new ByteArrayOutputStream();
StringReader in = new StringReader(base64);
decode(in, out);
in.close();
out.flush();
out.close();
return out.toByteArray();
}
/**
* Description of the Method
*
*@param in Description of the Parameter
*@param out Description of the Parameter
*@exception IOException Description of the Exception
*/
public static void encode(InputStream in, Writer out)
throws IOException {
int column = 0;
//--Process 3 bytes in each loop - writing 4 base64 chars to the output
while (true) {
int byte1 = in.read();
int byte2 = in.read();
int byte3 = in.read();
if (byte1 < 0) {
return;
}
//end-of-data
//--Wrap output at column 72
if (column >= 72) {
column = 0;
out.write('\n');
}
out.write(charset[byte1 >> 2]);
//write top 6 bits of byte 1
int index = (byte1 & 0x3) << 4;
//get bottom two bits of byte 1
if (byte2 < 0) {
//no more data
out.write(charset[index]);
out.write(paddingChar);
out.write(paddingChar);
return;
}
index += byte2 >> 4;
//add the top 4 bits of byte 2
out.write(charset[index]);
index = (byte2 & 0xf) << 2;
//get bottom 4 bits of byte 2
if (byte3 < 0) {
//more more data
out.write(charset[index]);
out.write(paddingChar);
return;
}
index += byte3 >> 6;
//add top 2 bits of byte 3
out.write(charset[index]);
out.write(charset[byte3 & 0x3f]);
//write bottom 6 bits of byte 3
//--Advance column counter
column += 4;
}
}
/**
* Description of the Method
*
*@param data Description of the Parameter
*@return Description of the Return Value
*/
public static String encode(byte[] data) {
try {
return encode(data, 0, data.length);
} catch (ArrayIndexOutOfBoundsException aiobe) {
return aiobe.toString();
}
}
/**
* Description of the Method
*
*@param data Description of the Parameter
*@param start Description of the Parameter
*@param length Description of the Parameter
*@return Description of the Return
* Value
*@exception ArrayIndexOutOfBoundsException Description of the Exception
*/
public static String encode(byte[] data, int start, int length)
throws ArrayIndexOutOfBoundsException {
StringWriter out = new StringWriter();
ByteArrayInputStream in = new ByteArrayInputStream(data, start, length);
try {
encode(in, out);
in.close();
out.flush();
out.close();
} catch (IOException ioe) {
return ioe.toString();
}
return out.toString();
}
/**
* If args.length > 0 then encode binary on stdin to base64 on stdout, else
* decode base64 on stdin to binary on stdout
*
*@param args The command line arguments
*@exception Exception Description of the Exception
*/
public static void main(String[] args) throws Exception {
if (args.length > 0) {
OutputStreamWriter out = new OutputStreamWriter(System.out);
encode(System.in, out);
out.flush();
return;
}
decode(new InputStreamReader(System.in), System.out);
System.out.flush();
}
}
Mini Shell