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// Copyright 2003-2010 Christian d'Heureuse, Inventec Informatik AG, Zurich, Switzerland
// www.source-code.biz, www.inventec.ch/chdh
//
// This module is multi-licensed and may be used under the terms
// of any of the following licenses:
//
// EPL, Eclipse Public License, V1.0 or later, http://www.eclipse.org/legal
// LGPL, GNU Lesser General Public License, V2.1 or later, http://www.gnu.org/licenses/lgpl.html
// GPL, GNU General Public License, V2 or later, http://www.gnu.org/licenses/gpl.html
// AL, Apache License, V2.0 or later, http://www.apache.org/licenses
// BSD, BSD License, http://www.opensource.org/licenses/bsd-license.php
// MIT, MIT License, http://www.opensource.org/licenses/MIT
//
// Please contact the author if you need another license.
// This module is provided "as is", without warranties of any kind.
package net.bull.javamelody.internal.model;
import java.util.Arrays;
/**
* A Base64 encoder/decoder.
*
*
* This class is used to encode and decode data in Base64 format as described in RFC 1521.
*
*
* Project home page: www.source-code.biz/base64coder/java
* Author: Christian d'Heureuse, Inventec Informatik AG, Zurich, Switzerland
* Multi-licensed: EPL / LGPL / GPL / AL / BSD / MIT.
* Changed on format and java syntax by Emeric Vernat
*/
public final class Base64Coder {
// The line separator string of the operating system.
private static final String SYSTEM_LINE_SEPARATOR = System.lineSeparator();
// Mapping table from 6-bit nibbles to Base64 characters.
private static final char[] MAP1 = new char[64];
static {
int i = 0;
for (char c = 'A'; c <= 'Z'; c++) {
MAP1[i++] = c;
}
for (char c = 'a'; c <= 'z'; c++) {
MAP1[i++] = c;
}
for (char c = '0'; c <= '9'; c++) {
MAP1[i++] = c;
}
MAP1[i++] = '+';
MAP1[i++] = '/';
}
// Mapping table from Base64 characters to 6-bit nibbles.
private static final byte[] MAP2 = new byte[128];
static {
Arrays.fill(MAP2, (byte) -1);
for (int i = 0; i < 64; i++) {
MAP2[MAP1[i]] = (byte) i;
}
}
// Dummy constructor.
private Base64Coder() {
}
/**
* Encodes a string into Base64 format.
* No blanks or line breaks are inserted.
* @param s A String to be encoded.
* @return A String containing the Base64 encoded data.
*/
public static String encodeString(String s) {
return new String(encode(s.getBytes()));
}
/**
* Encodes a byte array into Base 64 format and breaks the output into lines of 76 characters.
* This method is compatible with sun.misc.BASE64Encoder.encodeBuffer(byte[]).
* @param in An array containing the data bytes to be encoded.
* @return A String containing the Base64 encoded data, broken into lines.
*/
public static String encodeLines(byte[] in) {
return encodeLines(in, 0, in.length, 76, SYSTEM_LINE_SEPARATOR);
}
/**
* Encodes a byte array into Base 64 format and breaks the output into lines.
* @param in An array containing the data bytes to be encoded.
* @param iOff Offset of the first byte in in to be processed.
* @param iLen Number of bytes to be processed in in, starting at iOff.
* @param lineLen Line length for the output data. Should be a multiple of 4.
* @param lineSeparator The line separator to be used to separate the output lines.
* @return A String containing the Base64 encoded data, broken into lines.
*/
public static String encodeLines(byte[] in, int iOff, int iLen, int lineLen,
String lineSeparator) {
final int blockLen = lineLen * 3 / 4;
if (blockLen <= 0) {
throw new IllegalArgumentException();
}
final int lines = (iLen + blockLen - 1) / blockLen;
final int bufLen = (iLen + 2) / 3 * 4 + lines * lineSeparator.length();
final StringBuilder buf = new StringBuilder(bufLen);
int ip = 0;
while (ip < iLen) {
final int l = Math.min(iLen - ip, blockLen);
buf.append(encode(in, iOff + ip, l));
buf.append(lineSeparator);
ip += l;
}
return buf.toString();
}
/**
* Encodes a byte array into Base64 format.
* No blanks or line breaks are inserted in the output.
* @param in An array containing the data bytes to be encoded.
* @return A character array containing the Base64 encoded data.
*/
public static char[] encode(byte[] in) {
return encode(in, 0, in.length);
}
// /**
// * Encodes a byte array into Base64 format.
// * No blanks or line breaks are inserted in the output.
// * @param in An array containing the data bytes to be encoded.
// * @param iLen Number of bytes to process in in.
// * @return A character array containing the Base64 encoded data.
// */
// public static char[] encode(byte[] in, int iLen) {
// return encode(in, 0, iLen);
// }
/**
* Encodes a byte array into Base64 format.
* No blanks or line breaks are inserted in the output.
* @param in An array containing the data bytes to be encoded.
* @param iOff Offset of the first byte in in to be processed.
* @param iLen Number of bytes to process in in, starting at iOff.
* @return A character array containing the Base64 encoded data.
*/
public static char[] encode(byte[] in, int iOff, int iLen) { // NOPMD
final int oDataLen = (iLen * 4 + 2) / 3; // output length without padding
final int oLen = (iLen + 2) / 3 * 4; // output length including padding
final char[] out = new char[oLen];
int ip = iOff;
final int iEnd = iOff + iLen;
int op = 0;
while (ip < iEnd) {
final int i0 = in[ip++] & 0xff;
final int i1 = ip < iEnd ? in[ip++] & 0xff : 0;
final int i2 = ip < iEnd ? in[ip++] & 0xff : 0;
final int o0 = i0 >>> 2;
final int o1 = (i0 & 3) << 4 | i1 >>> 4;
final int o2 = (i1 & 0xf) << 2 | i2 >>> 6;
final int o3 = i2 & 0x3F;
out[op++] = MAP1[o0];
out[op++] = MAP1[o1];
out[op] = op < oDataLen ? MAP1[o2] : '=';
op++;
out[op] = op < oDataLen ? MAP1[o3] : '=';
op++;
}
return out;
}
/**
* Decodes a string from Base64 format.
* No blanks or line breaks are allowed within the Base64 encoded input data.
* @param s A Base64 String to be decoded.
* @return A String containing the decoded data.
*/
public static String decodeString(String s) {
return new String(decode(s));
}
/**
* Decodes a byte array from Base64 format and ignores line separators, tabs and blanks.
* CR, LF, Tab and Space characters are ignored in the input data.
* This method is compatible with sun.misc.BASE64Decoder.decodeBuffer(String).
* @param s A Base64 String to be decoded.
* @return An array containing the decoded data bytes.
*/
public static byte[] decodeLines(String s) {
final char[] buf = new char[s.length()];
int p = 0;
for (int ip = 0; ip < s.length(); ip++) {
final char c = s.charAt(ip);
if (c != ' ' && c != '\r' && c != '\n' && c != '\t') {
buf[p++] = c;
}
}
return decode(buf, 0, p);
}
/**
* Decodes a byte array from Base64 format.
* No blanks or line breaks are allowed within the Base64 encoded input data.
* @param s A Base64 String to be decoded.
* @return An array containing the decoded data bytes.
*/
public static byte[] decode(String s) {
return decode(s.toCharArray());
}
/**
* Decodes a byte array from Base64 format.
* No blanks or line breaks are allowed within the Base64 encoded input data.
* @param in A character array containing the Base64 encoded data.
* @return An array containing the decoded data bytes.
*/
public static byte[] decode(char[] in) {
return decode(in, 0, in.length);
}
/**
* Decodes a byte array from Base64 format.
* No blanks or line breaks are allowed within the Base64 encoded input data.
* @param in A character array containing the Base64 encoded data.
* @param iOff Offset of the first character in in to be processed.
* @param iLen Number of characters to process in in, starting at iOff.
* @return An array containing the decoded data bytes.
*/
// CHECKSTYLE:OFF
public static byte[] decode(char[] in, int iOff, int iLen) { // NOPMD
// CHECKSTYLE:ON
if (iLen % 4 != 0) {
throw new IllegalArgumentException(
"Length of Base64 encoded input string is not a multiple of 4.");
}
int iLength = iLen;
while (iLength > 0 && in[iOff + iLength - 1] == '=') {
iLength--;
}
final int oLen = iLength * 3 / 4;
final byte[] out = new byte[oLen];
int ip = iOff;
final int iEnd = iOff + iLength;
int op = 0;
while (ip < iEnd) {
final int i0 = in[ip++];
final int i1 = in[ip++];
final int i2 = ip < iEnd ? in[ip++] : 'A';
final int i3 = ip < iEnd ? in[ip++] : 'A';
if (i0 > 127 || i1 > 127 || i2 > 127 || i3 > 127) {
throw new IllegalArgumentException("Illegal character in Base64 encoded data.");
}
final int b0 = MAP2[i0];
final int b1 = MAP2[i1];
final int b2 = MAP2[i2];
final int b3 = MAP2[i3];
if (b0 < 0 || b1 < 0 || b2 < 0 || b3 < 0) {
throw new IllegalArgumentException("Illegal character in Base64 encoded data.");
}
final int o0 = b0 << 2 | b1 >>> 4;
final int o1 = (b1 & 0xf) << 4 | b2 >>> 2;
final int o2 = (b2 & 3) << 6 | b3;
out[op++] = (byte) o0;
if (op < oLen) {
out[op++] = (byte) o1;
}
if (op < oLen) {
out[op++] = (byte) o2;
}
}
return out;
}
} // end class Base64Coder