// 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 | |
// | |
// Please contact the author if you need another license. | |
// This module is provided "as is", without warranties of any kind. | |
package biz.source_code.base64Coder; | |
/** | |
* A Base64 encoder/decoder. | |
* | |
* <p> | |
* This class is used to encode and decode data in Base64 format as described in | |
* RFC 1521. | |
* | |
* <p> | |
* Project home page: <a | |
* href="http://www.source-code.biz/base64coder/java/">www. | |
* source-code.biz/base64coder/java</a><br> | |
* Author: Christian d'Heureuse, Inventec Informatik AG, Zurich, Switzerland<br> | |
* Multi-licensed: EPL / LGPL / GPL / AL / BSD. | |
*/ | |
public class Base64Coder { | |
// The line separator string of the operating system. | |
private static final String systemLineSeparator = System.getProperty("line.separator"); | |
// Mapping table from 6-bit nibbles to Base64 characters. | |
private static 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 byte[] map2 = new byte[128]; | |
static { | |
for (int i = 0; i < map2.length; i++) | |
map2[i] = -1; | |
for (int i = 0; i < 64; i++) | |
map2[map1[i]] = (byte) i; | |
} | |
/** | |
* 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 | |
* <code>sun.misc.BASE64Encoder.encodeBuffer(byte[])</code>. | |
* | |
* @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, systemLineSeparator); | |
} | |
/** | |
* 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 <code>in</code> to be processed. | |
* @param iLen | |
* Number of bytes to be processed in <code>in</code>, starting | |
* at <code>iOff</code>. | |
* @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) { | |
int blockLen = (lineLen * 3) / 4; | |
if (blockLen <= 0) | |
throw new IllegalArgumentException(); | |
int lines = (iLen + blockLen - 1) / blockLen; | |
int bufLen = ((iLen + 2) / 3) * 4 + lines * lineSeparator.length(); | |
StringBuilder buf = new StringBuilder(bufLen); | |
int ip = 0; | |
while (ip < iLen) { | |
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 <code>in</code>. | |
* @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 <code>in</code> to be processed. | |
* @param iLen | |
* Number of bytes to process in <code>in</code>, starting at | |
* <code>iOff</code>. | |
* @return A character array containing the Base64 encoded data. | |
*/ | |
public static char[] encode(byte[] in, int iOff, int iLen) { | |
int oDataLen = (iLen * 4 + 2) / 3; // output length without padding | |
int oLen = ((iLen + 2) / 3) * 4; // output length including padding | |
char[] out = new char[oLen]; | |
int ip = iOff; | |
int iEnd = iOff + iLen; | |
int op = 0; | |
while (ip < iEnd) { | |
int i0 = in[ip++] & 0xff; | |
int i1 = ip < iEnd ? in[ip++] & 0xff : 0; | |
int i2 = ip < iEnd ? in[ip++] & 0xff : 0; | |
int o0 = i0 >>> 2; | |
int o1 = ((i0 & 3) << 4) | (i1 >>> 4); | |
int o2 = ((i1 & 0xf) << 2) | (i2 >>> 6); | |
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. | |
* @throws IllegalArgumentException | |
* If the input is not valid Base64 encoded 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 | |
* <code>sun.misc.BASE64Decoder.decodeBuffer(String)</code>. | |
* | |
* @param s | |
* A Base64 String to be decoded. | |
* @return An array containing the decoded data bytes. | |
* @throws IllegalArgumentException | |
* If the input is not valid Base64 encoded data. | |
*/ | |
public static byte[] decodeLines(String s) { | |
char[] buf = new char[s.length()]; | |
int p = 0; | |
for (int ip = 0; ip < s.length(); ip++) { | |
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. | |
* @throws IllegalArgumentException | |
* If the input is not valid Base64 encoded data. | |
*/ | |
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. | |
* @throws IllegalArgumentException | |
* If the input is not valid Base64 encoded data. | |
*/ | |
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 <code>in</code> to be | |
* processed. | |
* @param iLen | |
* Number of characters to process in <code>in</code>, starting | |
* at <code>iOff</code>. | |
* @return An array containing the decoded data bytes. | |
* @throws IllegalArgumentException | |
* If the input is not valid Base64 encoded data. | |
*/ | |
public static byte[] decode(char[] in, int iOff, int iLen) { | |
if (iLen % 4 != 0) | |
throw new IllegalArgumentException( | |
"Length of Base64 encoded input string is not a multiple of 4."); | |
while (iLen > 0 && in[iOff + iLen - 1] == '=') | |
iLen--; | |
int oLen = (iLen * 3) / 4; | |
byte[] out = new byte[oLen]; | |
int ip = iOff; | |
int iEnd = iOff + iLen; | |
int op = 0; | |
while (ip < iEnd) { | |
int i0 = in[ip++]; | |
int i1 = in[ip++]; | |
int i2 = ip < iEnd ? in[ip++] : 'A'; | |
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."); | |
int b0 = map2[i0]; | |
int b1 = map2[i1]; | |
int b2 = map2[i2]; | |
int b3 = map2[i3]; | |
if (b0 < 0 || b1 < 0 || b2 < 0 || b3 < 0) | |
throw new IllegalArgumentException("Illegal character in Base64 encoded data."); | |
int o0 = (b0 << 2) | (b1 >>> 4); | |
int o1 = ((b1 & 0xf) << 4) | (b2 >>> 2); | |
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; | |
} | |
// Dummy constructor. | |
private Base64Coder() { | |
} | |
} // end class Base64Coder |