1 // Copyright 2003-2010 Christian d'Heureuse, Inventec Informatik AG, Zurich, Switzerland
2 // www.source-code.biz, www.inventec.ch/chdh
3 //
4 // This module is multi-licensed and may be used under the terms
5 // of any of the following licenses:
6 //
7 // EPL, Eclipse Public License, V1.0 or later, http://www.eclipse.org/legal
8 // LGPL, GNU Lesser General Public License, V2.1 or later, http://www.gnu.org/licenses/lgpl.html
9 // GPL, GNU General Public License, V2 or later, http://www.gnu.org/licenses/gpl.html
10 // AL, Apache License, V2.0 or later, http://www.apache.org/licenses
11 // BSD, BSD License, http://www.opensource.org/licenses/bsd-license.php
12 //
13 // Please contact the author if you need another license.
14 // This module is provided "as is", without warranties of any kind.
15
16 package org.yaml.snakeyaml.external.biz.base64Coder;
17
18 /**
19 * A Base64 encoder/decoder.
20 *
21 * <p>
22 * This class is used to encode and decode data in Base64 format as described in
23 * RFC 1521.
24 *
25 * <p>
26 * Project home page: <a
27 * href="http://www.source-code.biz/base64coder/java/">www.
28 * source-code.biz/base64coder/java</a><br>
29 * Author: Christian d'Heureuse, Inventec Informatik AG, Zurich, Switzerland<br>
30 * Multi-licensed: EPL / LGPL / GPL / AL / BSD.
31 */
32 public class Base64Coder {
33
34 // The line separator string of the operating system.
35 private static final String systemLineSeparator = System.getProperty("line.separator");
36
37 // Mapping table from 6-bit nibbles to Base64 characters.
38 private static char[] map1 = new char[64];
39 static {
40 int i = 0;
41 for (char c = 'A'; c <= 'Z'; c++)
42 map1[i++] = c;
43 for (char c = 'a'; c <= 'z'; c++)
44 map1[i++] = c;
45 for (char c = '0'; c <= '9'; c++)
46 map1[i++] = c;
47 map1[i++] = '+';
48 map1[i++] = '/';
49 }
50
51 // Mapping table from Base64 characters to 6-bit nibbles.
52 private static byte[] map2 = new byte[128];
53 static {
54 for (int i = 0; i < map2.length; i++)
55 map2[i] = -1;
56 for (int i = 0; i < 64; i++)
57 map2[map1[i]] = (byte) i;
58 }
59
60 /**
61 * Encodes a string into Base64 format. No blanks or line breaks are
62 * inserted.
63 *
64 * @param s
65 * A String to be encoded.
66 * @return A String containing the Base64 encoded data.
67 */
68 public static String encodeString(String s) {
69 return new String(encode(s.getBytes()));
70 }
71
72 /**
73 * Encodes a byte array into Base 64 format and breaks the output into lines
74 * of 76 characters. This method is compatible with
75 * <code>sun.misc.BASE64Encoder.encodeBuffer(byte[])</code>.
76 *
77 * @param in
78 * An array containing the data bytes to be encoded.
79 * @return A String containing the Base64 encoded data, broken into lines.
80 */
81 public static String encodeLines(byte[] in) {
82 return encodeLines(in, 0, in.length, 76, systemLineSeparator);
83 }
84
85 /**
86 * Encodes a byte array into Base 64 format and breaks the output into
87 * lines.
88 *
89 * @param in
90 * An array containing the data bytes to be encoded.
91 * @param iOff
92 * Offset of the first byte in <code>in</code> to be processed.
93 * @param iLen
94 * Number of bytes to be processed in <code>in</code>, starting
95 * at <code>iOff</code>.
96 * @param lineLen
97 * Line length for the output data. Should be a multiple of 4.
98 * @param lineSeparator
99 * The line separator to be used to separate the output lines.
100 * @return A String containing the Base64 encoded data, broken into lines.
101 */
102 public static String encodeLines(byte[] in, int iOff, int iLen, int lineLen,
103 String lineSeparator) {
104 int blockLen = (lineLen * 3) / 4;
105 if (blockLen <= 0)
106 throw new IllegalArgumentException();
107 int lines = (iLen + blockLen - 1) / blockLen;
108 int bufLen = ((iLen + 2) / 3) * 4 + lines * lineSeparator.length();
109 StringBuilder buf = new StringBuilder(bufLen);
110 int ip = 0;
111 while (ip < iLen) {
112 int l = Math.min(iLen - ip, blockLen);
113 buf.append(encode(in, iOff + ip, l));
114 buf.append(lineSeparator);
115 ip += l;
116 }
117 return buf.toString();
118 }
119
120 /**
121 * Encodes a byte array into Base64 format. No blanks or line breaks are
122 * inserted in the output.
123 *
124 * @param in
125 * An array containing the data bytes to be encoded.
126 * @return A character array containing the Base64 encoded data.
127 */
128 public static char[] encode(byte[] in) {
129 return encode(in, 0, in.length);
130 }
131
132 /**
133 * Encodes a byte array into Base64 format. No blanks or line breaks are
134 * inserted in the output.
135 *
136 * @param in
137 * An array containing the data bytes to be encoded.
138 * @param iLen
139 * Number of bytes to process in <code>in</code>.
140 * @return A character array containing the Base64 encoded data.
141 */
142 public static char[] encode(byte[] in, int iLen) {
143 return encode(in, 0, iLen);
144 }
145
146 /**
147 * Encodes a byte array into Base64 format. No blanks or line breaks are
148 * inserted in the output.
149 *
150 * @param in
151 * An array containing the data bytes to be encoded.
152 * @param iOff
153 * Offset of the first byte in <code>in</code> to be processed.
154 * @param iLen
155 * Number of bytes to process in <code>in</code>, starting at
156 * <code>iOff</code>.
157 * @return A character array containing the Base64 encoded data.
158 */
159 public static char[] encode(byte[] in, int iOff, int iLen) {
160 int oDataLen = (iLen * 4 + 2) / 3; // output length without padding
161 int oLen = ((iLen + 2) / 3) * 4; // output length including padding
162 char[] out = new char[oLen];
163 int ip = iOff;
164 int iEnd = iOff + iLen;
165 int op = 0;
166 while (ip < iEnd) {
167 int i0 = in[ip++] & 0xff;
168 int i1 = ip < iEnd ? in[ip++] & 0xff : 0;
169 int i2 = ip < iEnd ? in[ip++] & 0xff : 0;
170 int o0 = i0 >>> 2;
171 int o1 = ((i0 & 3) << 4) | (i1 >>> 4);
172 int o2 = ((i1 & 0xf) << 2) | (i2 >>> 6);
173 int o3 = i2 & 0x3F;
174 out[op++] = map1[o0];
175 out[op++] = map1[o1];
176 out[op] = op < oDataLen ? map1[o2] : '=';
177 op++;
178 out[op] = op < oDataLen ? map1[o3] : '=';
179 op++;
180 }
181 return out;
182 }
183
184 /**
185 * Decodes a string from Base64 format. No blanks or line breaks are allowed
186 * within the Base64 encoded input data.
187 *
188 * @param s
189 * A Base64 String to be decoded.
190 * @return A String containing the decoded data.
191 * @throws IllegalArgumentException
192 * If the input is not valid Base64 encoded data.
193 */
194 public static String decodeString(String s) {
195 return new String(decode(s));
196 }
197
198 /**
199 * Decodes a byte array from Base64 format and ignores line separators, tabs
200 * and blanks. CR, LF, Tab and Space characters are ignored in the input
201 * data. This method is compatible with
202 * <code>sun.misc.BASE64Decoder.decodeBuffer(String)</code>.
203 *
204 * @param s
205 * A Base64 String to be decoded.
206 * @return An array containing the decoded data bytes.
207 * @throws IllegalArgumentException
208 * If the input is not valid Base64 encoded data.
209 */
210 public static byte[] decodeLines(String s) {
211 char[] buf = new char[s.length()];
212 int p = 0;
213 for (int ip = 0; ip < s.length(); ip++) {
214 char c = s.charAt(ip);
215 if (c != ' ' && c != '\r' && c != '\n' && c != '\t')
216 buf[p++] = c;
217 }
218 return decode(buf, 0, p);
219 }
220
221 /**
222 * Decodes a byte array from Base64 format. No blanks or line breaks are
223 * allowed within the Base64 encoded input data.
224 *
225 * @param s
226 * A Base64 String to be decoded.
227 * @return An array containing the decoded data bytes.
228 * @throws IllegalArgumentException
229 * If the input is not valid Base64 encoded data.
230 */
231 public static byte[] decode(String s) {
232 return decode(s.toCharArray());
233 }
234
235 /**
236 * Decodes a byte array from Base64 format. No blanks or line breaks are
237 * allowed within the Base64 encoded input data.
238 *
239 * @param in
240 * A character array containing the Base64 encoded data.
241 * @return An array containing the decoded data bytes.
242 * @throws IllegalArgumentException
243 * If the input is not valid Base64 encoded data.
244 */
245 public static byte[] decode(char[] in) {
246 return decode(in, 0, in.length);
247 }
248
249 /**
250 * Decodes a byte array from Base64 format. No blanks or line breaks are
251 * allowed within the Base64 encoded input data.
252 *
253 * @param in
254 * A character array containing the Base64 encoded data.
255 * @param iOff
256 * Offset of the first character in <code>in</code> to be
257 * processed.
258 * @param iLen
259 * Number of characters to process in <code>in</code>, starting
260 * at <code>iOff</code>.
261 * @return An array containing the decoded data bytes.
262 * @throws IllegalArgumentException
263 * If the input is not valid Base64 encoded data.
264 */
265 public static byte[] decode(char[] in, int iOff, int iLen) {
266 if (iLen % 4 != 0)
267 throw new IllegalArgumentException(
268 "Length of Base64 encoded input string is not a multiple of 4.");
269 while (iLen > 0 && in[iOff + iLen - 1] == '=')
270 iLen--;
271 int oLen = (iLen * 3) / 4;
272 byte[] out = new byte[oLen];
273 int ip = iOff;
274 int iEnd = iOff + iLen;
275 int op = 0;
276 while (ip < iEnd) {
277 int i0 = in[ip++];
278 int i1 = in[ip++];
279 int i2 = ip < iEnd ? in[ip++] : 'A';
280 int i3 = ip < iEnd ? in[ip++] : 'A';
281 if (i0 > 127 || i1 > 127 || i2 > 127 || i3 > 127)
282 throw new IllegalArgumentException("Illegal character in Base64 encoded data.");
283 int b0 = map2[i0];
284 int b1 = map2[i1];
285 int b2 = map2[i2];
286 int b3 = map2[i3];
287 if (b0 < 0 || b1 < 0 || b2 < 0 || b3 < 0)
288 throw new IllegalArgumentException("Illegal character in Base64 encoded data.");
289 int o0 = (b0 << 2) | (b1 >>> 4);
290 int o1 = ((b1 & 0xf) << 4) | (b2 >>> 2);
291 int o2 = ((b2 & 3) << 6) | b3;
292 out[op++] = (byte) o0;
293 if (op < oLen)
294 out[op++] = (byte) o1;
295 if (op < oLen)
296 out[op++] = (byte) o2;
297 }
298 return out;
299 }
300
301 // Dummy constructor.
302 private Base64Coder() {
303 }
304
305 } // end class Base64Coder