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1
64
65 package com.jcorporate.expresso.core.misc;
66
67
77 public class Base64 {
78 static final private int bytesPerLine = 80;
80
81 private final static char[] vec = {
82 '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', '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', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/' };
91 private final static byte padding = (byte) '=';
92
93 public Base64() {
94 }
95
96
100 static private byte convertToNumber(byte inByte) {
101 if (inByte >= 'A' && inByte <= 'Z') {
102 return (byte) (inByte - 'A');
103 }
104 if (inByte >= 'a' && inByte <= 'z') {
105 return (byte) (inByte - 'a' + 26);
106 }
107 if (inByte >= '0' && inByte <= '9') {
108 return (byte) (inByte - '0' + 52);
109 }
110 if (inByte == '+') {
111 return (62);
112 }
113 if (inByte == '/') {
114 return (63);
115 }
116
117 return (-1);
118 }
119
120
128 static public byte[] decode(String  data)
129 throws IllegalArgumentException {
130
131 if (data == null) {
133 throw new IllegalArgumentException ("Base64.decode: data must not be null");
134 }
135 if (data.length() % 4 != 0) {
137 throw new IllegalArgumentException ("Base64.decode: data is not of proper length");
138 }
139
140 byte[] inputBuffer = data.getBytes();
141 int validInputCount = 0;
142 byte[] inBuffer = new byte[inputBuffer.length];
143 int dataLength = inputBuffer.length;
144
145 int i;
151
152 for (i = 0; i < dataLength; i++) {
153 byte temp = convertToNumber(inputBuffer[i]);
154
155 if (temp >= 0) {
156 inBuffer[i] = temp;
157 validInputCount++;
158 }
159 }
160
161 byte[] outBuffer = new byte[dataLength];
162 int startOut = 0;
163 int startIn = 0;
164
165 while (validInputCount > startIn) {
166 int dataLen = validInputCount;
167
168 if (dataLen - startIn > 3) {
169 outBuffer[startOut] = (byte) ((inBuffer[startIn] << 2) +
170 (inBuffer[startIn + 1] >>> 4));
171 outBuffer[startOut + 1] = (byte) ((inBuffer[startIn + 1] << 4) +
172 (inBuffer[startIn + 2] >>> 2));
173 outBuffer[startOut + 2] = (byte) ((inBuffer[startIn + 2] << 6) +
174 (inBuffer[startIn + 3]));
175 startOut += 3;
176 startIn += 4;
177 } else if (dataLen - startIn > 2) {
178 outBuffer[startOut] = (byte) ((inBuffer[startIn] << 2) +
179 (inBuffer[startIn + 1] >>> 4));
180 outBuffer[startOut + 1] = (byte) ((inBuffer[startIn + 1] << 4) +
181 (inBuffer[startIn + 2] >>> 2));
182 startOut += 2;
183 startIn += 3;
184 } else if (dataLen - startIn > 1) {
185 outBuffer[startOut] = (byte) ((inBuffer[startIn] << 2) +
186 (inBuffer[startIn + 1] >>> 4));
187 startOut += 1;
188 startIn += 2;
189 } else {
190 throw new IllegalStateException ("com.jcorporate.expresso.core.misc." +
191 "Base64.Decode: Corrupt Input Data");
192 }
193 }
194
195 byte[] finalOutput = new byte[startOut];
197
198 for (i = 0; i < startOut; i++) {
199 finalOutput[i] = outBuffer[i];
200 }
201
202 inBuffer = null;
203 outBuffer = null;
204
205 return finalOutput;
206 }
207
208
209
222 static public byte[] decodeNoPadding(String data)
223 throws IllegalArgumentException {
224 String myName = "Base64.decodeNoPadding";
225
226 if (data == null) {
227 throw new IllegalArgumentException (myName + " parameter 'data'" +
228 " must not be null");
229 }
230 if (data.length() == 0) {
231 throw new IllegalArgumentException (myName + " parameter 'data'" +
232 " must not be greater than zero length");
233 }
234 for (; data.length() % 4 != 0; data = data + "=") {
236 ;
237 }
238
239 return decode(data);
240 }
241
242
243
250 static public String encode(byte[] inBuffer)
251 throws IllegalArgumentException {
252 if (inBuffer.length == 0) {
253 throw new IllegalArgumentException ("Base64.encode: " +
254 "inBuffer must be > zero bytes in length");
255 }
256
257 int dataSize = inBuffer.length;
258 int startIn = 0;
259 int startOut = 0;
260
261 byte[] outBuffer;
264
265 if (dataSize < 4) {
266 outBuffer = new byte[4];
267 } else {
268 outBuffer = new byte[dataSize * 2];
269 }
270 while (startIn < dataSize) {
272 int dataLen = inBuffer.length;
273 byte a;
274 byte b;
275 byte c;
276
277 if ((startOut % bytesPerLine) + 4 > bytesPerLine) {
279 outBuffer[startOut] = (byte) '\r';
280 outBuffer[startOut + 1] = (byte) '\n';
281 startOut += 2;
282 }
283 if (dataLen - startIn > 2) {
284 a = inBuffer[startIn];
285 b = inBuffer[startIn + 1];
286 c = inBuffer[startIn + 2];
287 outBuffer[startOut] = (byte) vec[(a >>> 2) & 0x3F];
288 outBuffer[startOut + 1] = (byte) vec[((a << 4) & 0x30) +
289 ((b >>> 4) & 0xf)];
290 outBuffer[startOut + 2] = (byte) vec[((b << 2) & 0x3c) +
291 ((c >>> 6) & 0x3)];
292 outBuffer[startOut + 3] = (byte) vec[c & 0x3F];
293 startOut += 4;
294 startIn += 3;
295 } else if (dataLen - startIn == 1) {
296 a = inBuffer[startIn];
297 b = 0;
298 c = 0;
299 outBuffer[startOut] = (byte) vec[(a >>> 2) & 0x3F];
300 outBuffer[startOut + 1] = (byte) vec[((a << 4) & 0x30) +
301 ((b >>> 4) & 0xf)];
302 outBuffer[startOut + 2] = padding;
303 outBuffer[startOut + 3] = padding;
304 startOut += 4;
305 startIn += 2;
306 } else if (dataLen - startIn == 2) {
307 a = inBuffer[startIn];
308 b = inBuffer[startIn + 1];
309 c = 0;
310 outBuffer[startOut] = (byte) vec[(a >>> 2) & 0x3F];
311 outBuffer[startOut + 1] = (byte) vec[((a << 4) & 0x30) +
312 ((b >>> 4) & 0xf)];
313 outBuffer[startOut + 2] = (byte) vec[((b << 2) & 0x3c) +
314 ((c >>> 6) & 0x3)];
315 outBuffer[startOut + 3] = padding;
316 startOut += 4;
317 startIn += 2;
318 }
319 }
320
321 return new String (outBuffer, 0, startOut);
322 }
323
324
325
326
327
328
329
330
344 static public String encodeNoPadding(byte[] inBuffer)
345 throws IllegalArgumentException {
346 String stringWithPadding = encode(inBuffer);
347 int equalsPlacement = stringWithPadding.indexOf((int) '=');
348
349 if (equalsPlacement == -1) {
350 return stringWithPadding;
351 } else {
352 return stringWithPadding.substring(0, equalsPlacement);
353 }
354 }
355
356
357 }
358
359 |
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