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1
17
18 package org.apache.geronimo.util.encoders;
19
20 import java.io.IOException  ;
21 import java.io.OutputStream ;
22
23 public class Base64Encoder
24 implements Encoder
25 {
26 protected final byte[] encodingTable =
27 {
28 (byte)'A', (byte)'B', (byte)'C', (byte)'D', (byte)'E', (byte)'F', (byte)'G',
29 (byte)'H', (byte)'I', (byte)'J', (byte)'K', (byte)'L', (byte)'M', (byte)'N',
30 (byte)'O', (byte)'P', (byte)'Q', (byte)'R', (byte)'S', (byte)'T', (byte)'U',
31 (byte)'V', (byte)'W', (byte)'X', (byte)'Y', (byte)'Z',
32 (byte)'a', (byte)'b', (byte)'c', (byte)'d', (byte)'e', (byte)'f', (byte)'g',
33 (byte)'h', (byte)'i', (byte)'j', (byte)'k', (byte)'l', (byte)'m', (byte)'n',
34 (byte)'o', (byte)'p', (byte)'q', (byte)'r', (byte)'s', (byte)'t', (byte)'u',
35 (byte)'v',
36 (byte)'w', (byte)'x', (byte)'y', (byte)'z',
37 (byte)'0', (byte)'1', (byte)'2', (byte)'3', (byte)'4', (byte)'5', (byte)'6',
38 (byte)'7', (byte)'8', (byte)'9',
39 (byte)'+', (byte)'/'
40 };
41
42 protected byte padding = (byte)'=';
43
44
47 protected final byte[] decodingTable = new byte[128];
48
49 protected void initialiseDecodingTable()
50 {
51 for (int i = 0; i < encodingTable.length; i++)
52 {
53 decodingTable[encodingTable[i]] = (byte)i;
54 }
55 }
56
57 public Base64Encoder()
58 {
59 initialiseDecodingTable();
60 }
61
62
67 public int encode(
68 byte[] data,
69 int off,
70 int length,
71 OutputStream out)
72 throws IOException
73 {
74 int modulus = length % 3;
75 int dataLength = (length - modulus);
76 int a1, a2, a3;
77
78 for (int i = off; i < off + dataLength; i += 3)
79 {
80 a1 = data[i] & 0xff;
81 a2 = data[i + 1] & 0xff;
82 a3 = data[i + 2] & 0xff;
83
84 out.write(encodingTable[(a1 >>> 2) & 0x3f]);
85 out.write(encodingTable[((a1 << 4) | (a2 >>> 4)) & 0x3f]);
86 out.write(encodingTable[((a2 << 2) | (a3 >>> 6)) & 0x3f]);
87 out.write(encodingTable[a3 & 0x3f]);
88 }
89
90
93 int b1, b2, b3;
94 int d1, d2;
95
96 switch (modulus)
97 {
98 case 0:
99 break;
100 case 1:
101 d1 = data[off + dataLength] & 0xff;
102 b1 = (d1 >>> 2) & 0x3f;
103 b2 = (d1 << 4) & 0x3f;
104
105 out.write(encodingTable[b1]);
106 out.write(encodingTable[b2]);
107 out.write(padding);
108 out.write(padding);
109 break;
110 case 2:
111 d1 = data[off + dataLength] & 0xff;
112 d2 = data[off + dataLength + 1] & 0xff;
113
114 b1 = (d1 >>> 2) & 0x3f;
115 b2 = ((d1 << 4) | (d2 >>> 4)) & 0x3f;
116 b3 = (d2 << 2) & 0x3f;
117
118 out.write(encodingTable[b1]);
119 out.write(encodingTable[b2]);
120 out.write(encodingTable[b3]);
121 out.write(padding);
122 break;
123 }
124
125 return (dataLength / 3) * 4 + ((modulus == 0) ? 0 : 4);
126 }
127
128 private boolean ignore(
129 char c)
130 {
131 return (c == '\n' || c =='\r' || c == '\t' || c == ' ');
132 }
133
134
140 public int decode(
141 byte[] data,
142 int off,
143 int length,
144 OutputStream out)
145 throws IOException
146 {
147 byte[] bytes;
148 byte b1, b2, b3, b4;
149 int outLen = 0;
150
151 int end = off + length;
152
153 while (end > 0)
154 {
155 if (!ignore((char)data[end - 1]))
156 {
157 break;
158 }
159
160 end--;
161 }
162
163 int i = off;
164 int finish = end - 4;
165
166 while (i < finish)
167 {
168 while ((i < finish) && ignore((char)data[i]))
169 {
170 i++;
171 }
172
173 b1 = decodingTable[data[i++]];
174
175 while ((i < finish) && ignore((char)data[i]))
176 {
177 i++;
178 }
179
180 b2 = decodingTable[data[i++]];
181
182 while ((i < finish) && ignore((char)data[i]))
183 {
184 i++;
185 }
186
187 b3 = decodingTable[data[i++]];
188
189 while ((i < finish) && ignore((char)data[i]))
190 {
191 i++;
192 }
193
194 b4 = decodingTable[data[i++]];
195
196 out.write((b1 << 2) | (b2 >> 4));
197 out.write((b2 << 4) | (b3 >> 2));
198 out.write((b3 << 6) | b4);
199
200 outLen += 3;
201 }
202
203 if (data[end - 2] == padding)
204 {
205 b1 = decodingTable[data[end - 4]];
206 b2 = decodingTable[data[end - 3]];
207
208 out.write((b1 << 2) | (b2 >> 4));
209
210 outLen += 1;
211 }
212 else if (data[end - 1] == padding)
213 {
214 b1 = decodingTable[data[end - 4]];
215 b2 = decodingTable[data[end - 3]];
216 b3 = decodingTable[data[end - 2]];
217
218 out.write((b1 << 2) | (b2 >> 4));
219 out.write((b2 << 4) | (b3 >> 2));
220
221 outLen += 2;
222 }
223 else
224 {
225 b1 = decodingTable[data[end - 4]];
226 b2 = decodingTable[data[end - 3]];
227 b3 = decodingTable[data[end - 2]];
228 b4 = decodingTable[data[end - 1]];
229
230 out.write((b1 << 2) | (b2 >> 4));
231 out.write((b2 << 4) | (b3 >> 2));
232 out.write((b3 << 6) | b4);
233
234 outLen += 3;
235 }
236
237 return outLen;
238 }
239
240
246 public int decode(
247 String data,
248 OutputStream out)
249 throws IOException
250 {
251 byte[] bytes;
252 byte b1, b2, b3, b4;
253 int length = 0;
254
255 int end = data.length();
256
257 while (end > 0)
258 {
259 if (!ignore(data.charAt(end - 1)))
260 {
261 break;
262 }
263
264 end--;
265 }
266
267 int i = 0;
268 int finish = end - 4;
269
270 while (i < finish)
271 {
272 while ((i < finish) && ignore(data.charAt(i)))
273 {
274 i++;
275 }
276
277 b1 = decodingTable[data.charAt(i++)];
278
279 while ((i < finish) && ignore(data.charAt(i)))
280 {
281 i++;
282 }
283 b2 = decodingTable[data.charAt(i++)];
284
285 while ((i < finish) && ignore(data.charAt(i)))
286 {
287 i++;
288 }
289 b3 = decodingTable[data.charAt(i++)];
290
291 while ((i < finish) && ignore(data.charAt(i)))
292 {
293 i++;
294 }
295 b4 = decodingTable[data.charAt(i++)];
296
297 out.write((b1 << 2) | (b2 >> 4));
298 out.write((b2 << 4) | (b3 >> 2));
299 out.write((b3 << 6) | b4);
300
301 length += 3;
302 }
303
304 if (data.charAt(end - 2) == padding)
305 {
306 b1 = decodingTable[data.charAt(end - 4)];
307 b2 = decodingTable[data.charAt(end - 3)];
308
309 out.write((b1 << 2) | (b2 >> 4));
310
311 length += 1;
312 }
313 else if (data.charAt(end - 1) == padding)
314 {
315 b1 = decodingTable[data.charAt(end - 4)];
316 b2 = decodingTable[data.charAt(end - 3)];
317 b3 = decodingTable[data.charAt(end - 2)];
318
319 out.write((b1 << 2) | (b2 >> 4));
320 out.write((b2 << 4) | (b3 >> 2));
321
322 length += 2;
323 }
324 else
325 {
326 b1 = decodingTable[data.charAt(end - 4)];
327 b2 = decodingTable[data.charAt(end - 3)];
328 b3 = decodingTable[data.charAt(end - 2)];
329 b4 = decodingTable[data.charAt(end - 1)];
330
331 out.write((b1 << 2) | (b2 >> 4));
332 out.write((b2 << 4) | (b3 >> 2));
333 out.write((b3 << 6) | b4);
334
335 length += 3;
336 }
337
338 return length;
339 }
340 }
341 |
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