/base64coder-2010-12-19/src/main/java/biz/source_code/base64Coder/Base64Coder.java
Java | 226 lines | 99 code | 18 blank | 109 comment | 33 complexity | c070311ea6e99f139289e8147f10ab70 MD5 | raw file
- // 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 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 {
- 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