com.cloudinary.util.Base64Coder Maven / Gradle / Ivy
//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
//AGPL, GNU Affero General Public License V3 or later, http://www.gnu.org/licenses/agpl.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 com.cloudinary.util;
/**
* A Base64 encoder/decoder.
*
*
* This class is used to encode and decode data in Base64 format as described in
* RFC 1521.
*
* @author Christian d'Heureuse, Inventec Informatik AG, Zurich, Switzerland,
* www.source-code.biz
*/
@SuppressWarnings({"UnusedAssignment"})
public class Base64Coder {
// Mapping table from 6-bit nibbles to Base64 characters.
private static final char[] map1 = new char[64];
// Mapping table from Base64 characters to 6-bit nibbles.
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++] = '/';
}
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 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 iOff Offset of the first byte in {@code in} to be processed.
* @param iLen Number of bytes to process in {@code in}, starting at
* {@code iOff}.
* @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;
}
public static String encodeURLSafeString(String s) {
return encodeURLSafeString(s.getBytes());
}
public static String encodeURLSafeString(byte[] digest) {
char[] encode = encode(digest);
for (int i = 0; i < encode.length; i++) {
if (encode[i] == '+') {
encode[i] = '-';
} else if (encode[i] == '/') {
encode[i] = '_';
}
}
return new String(encode);
}
}