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1 package org.myoodb.util;
25
26 public final class MimeBase64
27 {
28 private int m_buf = 0;
29 private int m_buf_bytes = 0;
30 private int m_line_length = 0;
31 private char[] m_line = new char[74];
32 private StringBuilder  m_strOut = new StringBuilder ();
33 private java.io.ByteArrayOutputStream m_streamOut = new java.io.ByteArrayOutputStream ();
34
35 private byte[] m_token = new byte[4];
36 private byte[] m_bytes = new byte[3];
37 private int m_token_length = 0;
38
39 private final static byte NUL = 127;
40 private final static byte EOF = 126;
41
42 private final static char[] ENCODE_MAP =
43 {
44 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
45 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
46 '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'
47 };
48
57 private final static byte[] DECODE_MAP =
58 {
59 NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL,
60 NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, 62, NUL, NUL, NUL, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
61 NUL, NUL, NUL, EOF, NUL, NUL, NUL, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, NUL, NUL,
62 NUL, NUL, NUL, NUL, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, NUL, NUL, NUL,
63 NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL,
64 NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL,
65 NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL,
66 NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL,
67 NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL, NUL
68 };
69
78
87
96
105 private final void encode_token()
106 {
107 int i = m_line_length;
108 m_line[i] = ENCODE_MAP[0x3F & m_buf >> 18];
109 m_line[i + 1] = ENCODE_MAP[0x3F & m_buf >> 12];
110 m_line[i + 2] = ENCODE_MAP[0x3F & m_buf >> 6];
111 m_line[i + 3] = ENCODE_MAP[0x3F & m_buf];
112 m_line_length += 4;
113 m_buf = 0;
114 m_buf_bytes = 0;
115 }
116
117 private final void encode_partial_token()
118 {
119 int i = m_line_length;
120 m_line[i] = ENCODE_MAP[0x3F & m_buf >> 18];
121 m_line[i + 1] = ENCODE_MAP[0x3F & m_buf >> 12];
122
123 if (m_buf_bytes == 1)
124 {
125 m_line[i + 2] = '=';
126 }
127 else
128 {
129 m_line[i + 2] = ENCODE_MAP[0x3F & m_buf >> 6];
130 }
131
132 if (m_buf_bytes <= 2)
133 {
134 m_line[i + 3] = '=';
135 }
136 else
137 {
138 m_line[i + 3] = ENCODE_MAP[0x3F & m_buf];
139 }
140 m_line_length += 4;
141 m_buf = 0;
142 m_buf_bytes = 0;
143 }
144
145 private final void flush_line()
146 {
147 m_strOut.append(m_line, 0, m_line_length);
148 m_line_length = 0;
149 }
150
151 public final void translate(byte[] in)
152 {
153 int in_length = in.length;
154
155 for (int i = 0; i < in_length; i++)
156 {
157 if (m_buf_bytes == 0)
158 {
159 m_buf = m_buf & 0x00FFFF | in[i] << 16;
160 }
161 else if (m_buf_bytes == 1)
162 {
163 m_buf = m_buf & 0xFF00FF | in[i] << 8 & 0x00FFFF;
164 }
165 else
166 {
167 m_buf = m_buf & 0xFFFF00 | in[i] & 0x0000FF;
168 }
169
170 if (++m_buf_bytes == 3)
171 {
172 encode_token();
173 if (m_line_length >= 72)
174 {
175 flush_line();
176 }
177 }
178
179 if (i == (in_length - 1))
180 {
181 if (m_buf_bytes > 0 && m_buf_bytes < 3)
182 {
183 encode_partial_token();
184 }
185 if (m_line_length > 0)
186 {
187 flush_line();
188 }
189 }
190 }
191
192 for (int i = 0; i < m_line.length; i++)
193 {
194 m_line[i] = 0;
195 }
196 }
197
198 public char[] getCharArray()
199 {
200 char[] ch;
201
202 if (m_buf_bytes != 0)
203 {
204 encode_partial_token();
205 }
206 flush_line();
207 for (int i = 0; i < m_line.length; i++)
208 {
209 m_line[i] = 0;
210 }
211 ch = new char[m_strOut.length()];
212 m_strOut.getChars(0, m_strOut.length(), ch, 0);
213 return ch;
214 }
215
216 private void decode_token()
217 {
218 int num = m_token[0] << 18 | m_token[1] << 12 | m_token[2] << 6 | m_token[3];
219
220 m_bytes[0] = (byte)(0xFF & num >> 16);
221 m_bytes[1] = (byte)(0xFF & num >> 8);
222 m_bytes[2] = (byte)(0xFF & num);
223
224 m_streamOut.write(m_bytes, 0, 3);
225 }
226
227 private final void decode_final_token()
228 {
229
230 byte b0 = m_token[0];
231 byte b1 = m_token[1];
232 byte b2 = m_token[2];
233 byte b3 = m_token[3];
234
235 int eq_count = 0;
236
237 if (b0 == EOF) {
238 b0 = 0;
239 eq_count++;
240 }
241 if (b1 == EOF) {
242 b1 = 0;
243 eq_count++;
244 }
245 if (b2 == EOF) {
246 b2 = 0;
247 eq_count++;
248 }
249 if (b3 == EOF) {
250 b3 = 0;
251 eq_count++;
252 }
253
254 int num = b0 << 18 | b1 << 12 | b2 << 6 | b3;
255
256 m_streamOut.write((byte)(num >> 16));
257 if (eq_count <= 1)
258 {
259 m_streamOut.write((byte)(num >> 8 & 0xFF));
260 if (eq_count == 0)
261 {
262 m_streamOut.write((byte)(num & 0xFF));
263 }
264 }
265 }
266
267 private void eof()
268 {
269 if (m_token != null && m_token_length != 0)
270 {
271 while (m_token_length < 4)
272 {
273 m_token[m_token_length++] = EOF;
274 }
275 decode_final_token();
276 }
277 m_token_length = 0;
278 m_token = new byte[4];
279 m_bytes = new byte[3];
280 }
281
282 public final void translate(char[] ch)
283 {
284 translate(ch, 0, ch.length);
285 }
286
287 public final void translate(char[] ch, int offset, int length)
288 {
289 if (m_token == null)
290 {
291 return;
292 }
293
294 for (int i = offset; i < offset + length; i++)
295 {
296 byte t = DECODE_MAP[ch[i] & 0xff];
297
298 if (t == EOF)
299 {
300 eof();
301 }
302 else
303 {
304 if (t != NUL)
305 {
306 m_token[m_token_length++] = t;
307 }
308 }
309 if (m_token_length == 4)
310 {
311 decode_token();
312 m_token_length = 0;
313 }
314 }
315 }
316
317 public byte[] getByteArray()
318 {
319 eof();
320 return m_streamOut.toByteArray();
321 }
322 }
323 |
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