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/Users/lyon/j4p/src/utils/Base64.java
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1 package utils;
2
3 /**
4 * Encodes and decodes to and from Base64 notation.
5 * <p/>
6 * <p/>
7 * Change Log:
8 * </p>
9 * <ul>
10 * <li>v2.1 - Cleaned up javadoc comments and unused variables and methods. Added
11 * some convenience methods for reading and writing to and from files.</li>
12 * <li>v2.0.2 - Now specifies UTF-8 encoding in places where the code fails on systems
13 * with other encodings (like EBCDIC).</li>
14 * <li>v2.0.1 - Fixed an error when decoding a single byte, that is, when the
15 * encoded data was a single byte.</li>
16 * <li>v2.0 - I got rid of methods that used booleans to set options.
17 * Now everything is more consolidated and cleaner. The code now detects
18 * when data that's being decoded is gzip-compressed and will decompress it
19 * automatically. Generally things are cleaner. You'll probably have to
20 * change some method calls that you were making to support the new
21 * options format (<tt>int</tt>s that you "OR" together).</li>
22 * <li>v1.5.1 - Fixed bug when decompressing and decoding to a
23 * byte[] using <tt>decode( String s, boolean gzipCompressed )</tt>.
24 * Added the ability to "suspend" encoding in the Output Stream so
25 * you can turn on and off the encoding if you need to embed base64
26 * data in an otherwise "normal" stream (like an XML file).</li>
27 * <li>v1.5 - Output stream pases on flush() command but doesn't do anything itself.
28 * This helps when using GZIP streams.
29 * Added the ability to GZip-compress objects before encoding them.</li>
30 * <li>v1.4 - Added helper methods to read/write files.</li>
31 * <li>v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.</li>
32 * <li>v1.3.5 - Added flag to turn on and off line breaks. Fixed bug in input stream
33 * where last buffer being read, if not completely full, was not returned.</li>
34 * <li>v1.3.4 - Fixed when "improperly padded stream" error was thrown at the wrong time.</li>
35 * <li>v1.3.3 - Fixed I/O streams which were totally messed up.</li>
36 * </ul>
37 * <p/>
38 * <p/>
39 * I am placing this code in the Public Domain. Do with it as you will.
40 * This software comes with no guarantees or warranties but with
41 * plenty of well-wishing instead!
42 * Please visit <a href="http://iharder.net/base64">http://iharder.net/base64</a>
43 * periodically to check for updates or to contribute improvements.
44 * </p>
45 *
46 * @author Robert Harder
47 * @author rob@iharder.net
48 * @version 2.1
49 */
50 public class Base64 {
51
52 /* ******** P U B L I C F I E L D S ******** */
53
54
55 /**
56 * No options specified. Value is zero.
57 */
58 public final static int NO_OPTIONS = 0;
59
60 /**
61 * Specify encoding.
62 */
63 public final static int ENCODE = 1;
64
65
66 /**
67 * Specify decoding.
68 */
69 public final static int DECODE = 0;
70
71
72 /**
73 * Specify that data should be gzip-compressed.
74 */
75 public final static int GZIP = 2;
76
77
78 /**
79 * Don't break lines when encoding (violates strict Base64 specification)
80 */
81 public final static int DONT_BREAK_LINES = 8;
82
83
84 /* ******** P R I V A T E F I E L D S ******** */
85
86
87 /**
88 * Maximum line length (76) of Base64 output.
89 */
90 private final static int MAX_LINE_LENGTH = 76;
91
92
93 /**
94 * The equals sign (=) as a byte.
95 */
96 private final static byte EQUALS_SIGN = (byte) '=';
97
98
99 /**
100 * The new line character (\n) as a byte.
101 */
102 private final static byte NEW_LINE = (byte) '\n';
103
104
105 /**
106 * Preferred encoding.
107 */
108 private final static String PREFERRED_ENCODING = "UTF-8";
109
110
111 /**
112 * The 64 valid Base64 values.
113 */
114 private final static byte[] ALPHABET;
115 private final static byte[] _NATIVE_ALPHABET = /* May be something funny like EBCDIC */
116 {
117 (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G',
118 (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N',
119 (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U',
120 (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z',
121 (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g',
122 (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n',
123 (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u',
124 (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z',
125 (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5',
126 (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '+', (byte) '/'
127 };
128
129 /** Determine which ALPHABET to use. */
130 static {
131 byte[] __bytes;
132 try {
133 __bytes =
134 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".getBytes(PREFERRED_ENCODING);
135 } // end try
136 catch (java.io.UnsupportedEncodingException use) {
137 __bytes = _NATIVE_ALPHABET; // Fall back to native encoding
138 } // end catch
139 ALPHABET = __bytes;
140 } // end static
141
142
143 /**
144 * Translates a Base64 value to either its 6-bit reconstruction value
145 * or a negative number indicating some other meaning.
146 */
147 private final static byte[] DECODABET =
148 {
149 -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8
150 -5, -5, // Whitespace: Tab and Linefeed
151 -9, -9, // Decimal 11 - 12
152 -5, // Whitespace: Carriage Return
153 -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
154 -9, -9, -9, -9, -9, // Decimal 27 - 31
155 -5, // Whitespace: Space
156 -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
157 62, // Plus sign at decimal 43
158 -9, -9, -9, // Decimal 44 - 46
159 63, // Slash at decimal 47
160 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
161 -9, -9, -9, // Decimal 58 - 60
162 -1, // Equals sign at decimal 61
163 -9, -9, -9, // Decimal 62 - 64
164 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through 'N'
165 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' through 'Z'
166 -9, -9, -9, -9, -9, -9, // Decimal 91 - 96
167 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' through 'm'
168 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' through 'z'
169 -9, -9, -9, -9 // Decimal 123 - 126
170 /*,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 127 - 139
171 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 140 - 152
172 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 153 - 165
173 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 166 - 178
174 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 179 - 191
175 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 192 - 204
176 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 205 - 217
177 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 218 - 230
178 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 231 - 243
179 -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9 // Decimal 244 - 255 */
180 };
181
182 // I think I end up not using the BAD_ENCODING indicator.
183 //private final static byte BAD_ENCODING = -9; // Indicates error in encoding
184 private final static byte WHITE_SPACE_ENC = -5; // Indicates white space in encoding
185 private final static byte EQUALS_SIGN_ENC = -1; // Indicates equals sign in encoding
186
187
188 /**
189 * Defeats instantiation.
190 */
191 private Base64() {
192 }
193
194
195
196 /* ******** E N C O D I N G M E T H O D S ******** */
197
198
199 /**
200 * Encodes up to the first three bytes of array <var>threeBytes</var>
201 * and returns a four-byte array in Base64 notation.
202 * The actual number of significant bytes in your array is
203 * given by <var>numSigBytes</var>.
204 * The array <var>threeBytes</var> needs only be as big as
205 * <var>numSigBytes</var>.
206 * Code can reuse a byte array by passing a four-byte array as <var>b4</var>.
207 *
208 * @param b4 A reusable byte array to reduce array instantiation
209 * @param threeBytes the array to convert
210 * @param numSigBytes the number of significant bytes in your array
211 * @return four byte array in Base64 notation.
212 * @since 1.5.1
213 */
214 private static byte[] encode3to4(byte[] b4, byte[] threeBytes, int numSigBytes) {
215 encode3to4(threeBytes, 0, numSigBytes, b4, 0);
216 return b4;
217 } // end encode3to4
218
219
220 /**
221 * Encodes up to three bytes of the array <var>source</var>
222 * and writes the resulting four Base64 bytes to <var>destination</var>.
223 * The source and destination arrays can be manipulated
224 * anywhere along their length by specifying
225 * <var>srcOffset</var> and <var>destOffset</var>.
226 * This method does not check to make sure your arrays
227 * are large enough to accomodate <var>srcOffset</var> + 3 for
228 * the <var>source</var> array or <var>destOffset</var> + 4 for
229 * the <var>destination</var> array.
230 * The actual number of significant bytes in your array is
231 * given by <var>numSigBytes</var>.
232 *
233 * @param source the array to convert
234 * @param srcOffset the index where conversion begins
235 * @param numSigBytes the number of significant bytes in your array
236 * @param destination the array to hold the conversion
237 * @param destOffset the index where output will be put
238 * @return the <var>destination</var> array
239 * @since 1.3
240 */
241 private static byte[] encode3to4(byte[] source, int srcOffset, int numSigBytes,
242 byte[] destination, int destOffset) {
243 // 1 2 3
244 // 01234567890123456789012345678901 Bit position
245 // --------000000001111111122222222 Array position from threeBytes
246 // --------| || || || | Six bit groups to index ALPHABET
247 // >>18 >>12 >> 6 >> 0 Right shift necessary
248 // 0x3f 0x3f 0x3f Additional AND
249
250 // Create buffer with zero-padding if there are only one or two
251 // significant bytes passed in the array.
252 // We have to shift left 24 in order to flush out the 1's that appear
253 // when Java treats a value as negative that is cast from a byte to an int.
254 int inBuff = (numSigBytes > 0 ? ((source[srcOffset] << 24) >>> 8) : 0)
255 |
256 (numSigBytes > 1 ? ((source[srcOffset + 1] << 24) >>> 16) : 0)
257 | (numSigBytes > 2 ? ((source[srcOffset + 2] << 24) >>> 24) : 0);
258
259 switch (numSigBytes) {
260 case 3:
261 destination[destOffset] = ALPHABET[(inBuff >>> 18)];
262 destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
263 destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
264 destination[destOffset + 3] = ALPHABET[(inBuff) & 0x3f];
265 return destination;
266
267 case 2:
268 destination[destOffset] = ALPHABET[(inBuff >>> 18)];
269 destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
270 destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
271 destination[destOffset + 3] = EQUALS_SIGN;
272 return destination;
273
274 case 1:
275 destination[destOffset] = ALPHABET[(inBuff >>> 18)];
276 destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
277 destination[destOffset + 2] = EQUALS_SIGN;
278 destination[destOffset + 3] = EQUALS_SIGN;
279 return destination;
280
281 default:
282 return destination;
283 } // end switch
284 } // end encode3to4
285
286
287 /**
288 * Serializes an object and returns the Base64-encoded
289 * version of that serialized object. If the object
290 * cannot be serialized or there is another error,
291 * the method will return <tt>null</tt>.
292 * The object is not GZip-compressed before being encoded.
293 *
294 * @param serializableObject The object to encode
295 * @return The Base64-encoded object
296 * @since 1.4
297 */
298 public static String encodeObject(java.io.Serializable serializableObject) {
299 return encodeObject(serializableObject, NO_OPTIONS);
300 } // end encodeObject
301
302
303 /**
304 * Serializes an object and returns the Base64-encoded
305 * version of that serialized object. If the object
306 * cannot be serialized or there is another error,
307 * the method will return <tt>null</tt>.
308 * <p/>
309 * Valid options:<pre>
310 * GZIP: gzip-compresses object before encoding it.
311 * DONT_BREAK_LINES: don't break lines at 76 characters
312 * <i>Note: Technically, this makes your encoding non-compliant.</i>
313 * </pre>
314 * <p/>
315 * Example: <code>encodeObject( myObj, Base64.GZIP )</code> or
316 * <p/>
317 * Example: <code>encodeObject( myObj, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
318 *
319 * @param serializableObject The object to encode
320 * @param options Specified options
321 * @return The Base64-encoded object
322 * @see Base64#GZIP
323 * @see Base64#DONT_BREAK_LINES
324 * @since 2.0
325 */
326 public static String encodeObject(java.io.Serializable serializableObject, int options) {
327 // Streams
328 java.io.ByteArrayOutputStream baos = null;
329 java.io.OutputStream b64os = null;
330 java.io.ObjectOutputStream oos = null;
331 java.util.zip.GZIPOutputStream gzos = null;
332
333 // Isolate options
334 int gzip = (options & GZIP);
335 int dontBreakLines = (options & DONT_BREAK_LINES);
336
337 try {
338 // ObjectOutputStream -> (GZIP) -> Base64 -> ByteArrayOutputStream
339 baos = new java.io.ByteArrayOutputStream();
340 b64os = new Base64.OutputStream(baos, ENCODE | dontBreakLines);
341
342 // GZip?
343 if (gzip == GZIP) {
344 gzos = new java.util.zip.GZIPOutputStream(b64os);
345 oos = new java.io.ObjectOutputStream(gzos);
346 } // end if: gzip
347 else
348 oos = new java.io.ObjectOutputStream(b64os);
349
350 oos.writeObject(serializableObject);
351 } // end try
352 catch (java.io.IOException e) {
353 e.printStackTrace();
354 return null;
355 } // end catch
356 finally {
357 try {
358 oos.close();
359 } catch (Exception e) {
360 }
361 try {
362 gzos.close();
363 } catch (Exception e) {
364 }
365 try {
366 b64os.close();
367 } catch (Exception e) {
368 }
369 try {
370 baos.close();
371 } catch (Exception e) {
372 }
373 } // end finally
374
375 // Return value according to relevant encoding.
376 try {
377 return new String(baos.toByteArray(), PREFERRED_ENCODING);
378 } // end try
379 catch (java.io.UnsupportedEncodingException uue) {
380 return new String(baos.toByteArray());
381 } // end catch
382
383 } // end encode
384
385
386 /**
387 * Encodes a byte array into Base64 notation.
388 * Does not GZip-compress data.
389 *
390 * @param source The data to convert
391 * @since 1.4
392 */
393 public static String encodeBytes(byte[] source) {
394 return encodeBytes(source, 0, source.length, NO_OPTIONS);
395 } // end encodeBytes
396
397
398 /**
399 * Encodes a byte array into Base64 notation.
400 * <p/>
401 * Valid options:<pre>
402 * GZIP: gzip-compresses object before encoding it.
403 * DONT_BREAK_LINES: don't break lines at 76 characters
404 * <i>Note: Technically, this makes your encoding non-compliant.</i>
405 * </pre>
406 * <p/>
407 * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
408 * <p/>
409 * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
410 *
411 * @param source The data to convert
412 * @param options Specified options
413 * @see Base64#GZIP
414 * @see Base64#DONT_BREAK_LINES
415 * @since 2.0
416 */
417 public static String encodeBytes(byte[] source, int options) {
418 return encodeBytes(source, 0, source.length, options);
419 } // end encodeBytes
420
421
422 /**
423 * Encodes a byte array into Base64 notation.
424 * Does not GZip-compress data.
425 *
426 * @param source The data to convert
427 * @param off Offset in array where conversion should begin
428 * @param len Length of data to convert
429 * @since 1.4
430 */
431 public static String encodeBytes(byte[] source, int off, int len) {
432 return encodeBytes(source, off, len, NO_OPTIONS);
433 } // end encodeBytes
434
435
436 /**
437 * Encodes a byte array into Base64 notation.
438 * <p/>
439 * Valid options:<pre>
440 * GZIP: gzip-compresses object before encoding it.
441 * DONT_BREAK_LINES: don't break lines at 76 characters
442 * <i>Note: Technically, this makes your encoding non-compliant.</i>
443 * </pre>
444 * <p/>
445 * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
446 * <p/>
447 * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
448 *
449 * @param source The data to convert
450 * @param off Offset in array where conversion should begin
451 * @param len Length of data to convert
452 * @param options Specified options
453 * @see Base64#GZIP
454 * @see Base64#DONT_BREAK_LINES
455 * @since 2.0
456 */
457 public static String encodeBytes(byte[] source, int off, int len, int options) {
458 // Isolate options
459 int dontBreakLines = (options & DONT_BREAK_LINES);
460 int gzip = (options & GZIP);
461
462 // Compress?
463 if (gzip == GZIP) {
464 java.io.ByteArrayOutputStream baos = null;
465 java.util.zip.GZIPOutputStream gzos = null;
466 Base64.OutputStream b64os = null;
467
468
469 try {
470 // GZip -> Base64 -> ByteArray
471 baos = new java.io.ByteArrayOutputStream();
472 b64os = new Base64.OutputStream(baos, ENCODE | dontBreakLines);
473 gzos = new java.util.zip.GZIPOutputStream(b64os);
474
475 gzos.write(source, off, len);
476 gzos.close();
477 } // end try
478 catch (java.io.IOException e) {
479 e.printStackTrace();
480 return null;
481 } // end catch
482 finally {
483 try {
484 gzos.close();
485 } catch (Exception e) {
486 }
487 try {
488 b64os.close();
489 } catch (Exception e) {
490 }
491 try {
492 baos.close();
493 } catch (Exception e) {
494 }
495 } // end finally
496
497 // Return value according to relevant encoding.
498 try {
499 return new String(baos.toByteArray(), PREFERRED_ENCODING);
500 } // end try
501 catch (java.io.UnsupportedEncodingException uue) {
502 return new String(baos.toByteArray());
503 } // end catch
504 } // end if: compress
505
506 // Else, don't compress. Better not to use streams at all then.
507 else {
508 // Convert option to boolean in way that code likes it.
509 boolean breakLines = dontBreakLines == 0;
510
511 int len43 = len * 4 / 3;
512 byte[] outBuff = new byte[(len43) // Main 4:3
513 +
514 ((len % 3) > 0 ? 4 : 0) // Account for padding
515 + (breakLines ? (len43 / MAX_LINE_LENGTH) : 0)]; // New lines
516 int d = 0;
517 int e = 0;
518 int len2 = len - 2;
519 int lineLength = 0;
520 for (; d < len2; d += 3, e += 4) {
521 encode3to4(source, d + off, 3, outBuff, e);
522
523 lineLength += 4;
524 if (breakLines && lineLength == MAX_LINE_LENGTH) {
525 outBuff[e + 4] = NEW_LINE;
526 e++;
527 lineLength = 0;
528 } // end if: end of line
529 } // en dfor: each piece of array
530
531 if (d < len) {
532 encode3to4(source, d + off, len - d, outBuff, e);
533 e += 4;
534 } // end if: some padding needed
535
536
537 // Return value according to relevant encoding.
538 try {
539 return new String(outBuff, 0, e, PREFERRED_ENCODING);
540 } // end try
541 catch (java.io.UnsupportedEncodingException uue) {
542 return new String(outBuff, 0, e);
543 } // end catch
544
545 } // end else: don't compress
546
547 } // end encodeBytes
548
549
550
551
552
553 /* ******** D E C O D I N G M E T H O D S ******** */
554
555
556 /**
557 * Decodes four bytes from array <var>source</var>
558 * and writes the resulting bytes (up to three of them)
559 * to <var>destination</var>.
560 * The source and destination arrays can be manipulated
561 * anywhere along their length by specifying
562 * <var>srcOffset</var> and <var>destOffset</var>.
563 * This method does not check to make sure your arrays
564 * are large enough to accomodate <var>srcOffset</var> + 4 for
565 * the <var>source</var> array or <var>destOffset</var> + 3 for
566 * the <var>destination</var> array.
567 * This method returns the actual number of bytes that
568 * were converted from the Base64 encoding.
569 *
570 * @param source the array to convert
571 * @param srcOffset the index where conversion begins
572 * @param destination the array to hold the conversion
573 * @param destOffset the index where output will be put
574 * @return the number of decoded bytes converted
575 * @since 1.3
576 */
577 private static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset) {
578 // Example: Dk==
579 if (source[srcOffset + 2] == EQUALS_SIGN) {
580 // Two ways to do the same thing. Don't know which way I like best.
581 //int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
582 // | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 );
583 int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
584 | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12);
585
586 destination[destOffset] = (byte) (outBuff >>> 16);
587 return 1;
588 }
589
590 // Example: DkL=
591 else if (source[srcOffset + 3] == EQUALS_SIGN) {
592 // Two ways to do the same thing. Don't know which way I like best.
593 //int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
594 // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
595 // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 );
596 int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
597 |
598 ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
599 | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6);
600
601 destination[destOffset] = (byte) (outBuff >>> 16);
602 destination[destOffset + 1] = (byte) (outBuff >>> 8);
603 return 2;
604 }
605
606 // Example: DkLE
607 else {
608 try {
609 // Two ways to do the same thing. Don't know which way I like best.
610 //int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
611 // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
612 // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 )
613 // | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 );
614 int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
615 |
616 ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
617 |
618 ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6)
619 | ((DECODABET[source[srcOffset + 3]] & 0xFF));
620
621
622 destination[destOffset] = (byte) (outBuff >> 16);
623 destination[destOffset + 1] = (byte) (outBuff >> 8);
624 destination[destOffset + 2] = (byte) (outBuff);
625
626 return 3;
627 } catch (Exception e) {
628 System.out.println("" + source[srcOffset] + ": " + (DECODABET[source[srcOffset]]));
629 System.out.println("" + source[srcOffset + 1] + ": " + (DECODABET[source[srcOffset + 1]]));
630 System.out.println("" + source[srcOffset + 2] + ": " + (DECODABET[source[srcOffset + 2]]));
631 System.out.println("" + source[srcOffset + 3] + ": " + (DECODABET[source[srcOffset + 3]]));
632 return -1;
633 } //e nd catch
634 }
635 } // end decodeToBytes
636
637
638 /**
639 * Very low-level access to decoding ASCII characters in
640 * the form of a byte array. Does not support automatically
641 * gunzipping or any other "fancy" features.
642 *
643 * @param source The Base64 encoded data
644 * @param off The offset of where to begin decoding
645 * @param len The length of characters to decode
646 * @return decoded data
647 * @since 1.3
648 */
649 public static byte[] decode(byte[] source, int off, int len) {
650 int len34 = len * 3 / 4;
651 byte[] outBuff = new byte[len34]; // Upper limit on size of output
652 int outBuffPosn = 0;
653
654 byte[] b4 = new byte[4];
655 int b4Posn = 0;
656 int i = 0;
657 byte sbiCrop = 0;
658 byte sbiDecode = 0;
659 for (i = off; i < off + len; i++) {
660 sbiCrop = (byte) (source[i] & 0x7f); // Only the low seven bits
661 sbiDecode = DECODABET[sbiCrop];
662
663 if (sbiDecode >= WHITE_SPACE_ENC) // White space, Equals sign or better
664 {
665 if (sbiDecode >= EQUALS_SIGN_ENC) {
666 b4[b4Posn++] = sbiCrop;
667 if (b4Posn > 3) {
668 outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn);
669 b4Posn = 0;
670
671 // If that was the equals sign, break out of 'for' loop
672 if (sbiCrop == EQUALS_SIGN)
673 break;
674 } // end if: quartet built
675
676 } // end if: equals sign or better
677
678 } // end if: white space, equals sign or better
679 else {
680 System.err.println("Bad Base64 input character at " + i + ": " + source[i] + "(decimal)");
681 return null;
682 } // end else:
683 } // each input character
684
685 byte[] out = new byte[outBuffPosn];
686 System.arraycopy(outBuff, 0, out, 0, outBuffPosn);
687 return out;
688 } // end decode
689
690
691 /**
692 * Decodes data from Base64 notation, automatically
693 * detecting gzip-compressed data and decompressing it.
694 *
695 * @param s the string to decode
696 * @return the decoded data
697 * @since 1.4
698 */
699 public static byte[] decode(String s) {
700 byte[] bytes;
701 try {
702 bytes = s.getBytes(PREFERRED_ENCODING);
703 } // end try
704 catch (java.io.UnsupportedEncodingException uee) {
705 bytes = s.getBytes();
706 } // end catch
707 //</change>
708
709 // Decode
710 bytes = decode(bytes, 0, bytes.length);
711
712
713 // Check to see if it's gzip-compressed
714 // GZIP Magic Two-Byte Number: 0x8b1f (35615)
715 if (bytes != null && bytes.length >= 4) {
716
717 int head = ((int) bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00);
718 if (java.util.zip.GZIPInputStream.GZIP_MAGIC == head) {
719 java.io.ByteArrayInputStream bais = null;
720 java.util.zip.GZIPInputStream gzis = null;
721 java.io.ByteArrayOutputStream baos = null;
722 byte[] buffer = new byte[2048];
723 int length = 0;
724
725 try {
726 baos = new java.io.ByteArrayOutputStream();
727 bais = new java.io.ByteArrayInputStream(bytes);
728 gzis = new java.util.zip.GZIPInputStream(bais);
729
730 while ((length = gzis.read(buffer)) >= 0) {
731 baos.write(buffer, 0, length);
732 } // end while: reading input
733
734 // No error? Get new bytes.
735 bytes = baos.toByteArray();
736
737 } // end try
738 catch (java.io.IOException e) {
739 // Just return originally-decoded bytes
740 } // end catch
741 finally {
742 try {
743 baos.close();
744 } catch (Exception e) {
745 }
746 try {
747 gzis.close();
748 } catch (Exception e) {
749 }
750 try {
751 bais.close();
752 } catch (Exception e) {
753 }
754 } // end finally
755
756 } // end if: gzipped
757 } // end if: bytes.length >= 2
758
759 return bytes;
760 } // end decode
761
762
763 /**
764 * Attempts to decode Base64 data and deserialize a Java
765 * Object within. Returns <tt>null</tt> if there was an error.
766 *
767 * @param encodedObject The Base64 data to decode
768 * @return The decoded and deserialized object
769 * @since 1.5
770 */
771 public static Object decodeToObject(String encodedObject) {
772 // Decode and gunzip if necessary
773 byte[] objBytes = decode(encodedObject);
774
775 java.io.ByteArrayInputStream bais = null;
776 java.io.ObjectInputStream ois = null;
777 Object obj = null;
778
779 try {
780 bais = new java.io.ByteArrayInputStream(objBytes);
781 ois = new java.io.ObjectInputStream(bais);
782
783 obj = ois.readObject();
784 } // end try
785 catch (java.io.IOException e) {
786 e.printStackTrace();
787 obj = null;
788 } // end catch
789 catch (java.lang.ClassNotFoundException e) {
790 e.printStackTrace();
791 obj = null;
792 } // end catch
793 finally {
794 try {
795 bais.close();
796 } catch (Exception e) {
797 }
798 try {
799 ois.close();
800 } catch (Exception e) {
801 }
802 } // end finally
803
804 return obj;
805 } // end decodeObject
806
807
808 /**
809 * Convenience method for encoding data to a file.
810 *
811 * @param dataToEncode byte array of data to encode in base64 form
812 * @param filename Filename for saving encoded data
813 * @return <tt>true</tt> if successful, <tt>false</tt> otherwise
814 * @since 2.1
815 */
816 public static boolean encodeToFile(byte[] dataToEncode, String filename) {
817 boolean success = false;
818 Base64.OutputStream bos = null;
819 try {
820 bos = new Base64.OutputStream(new java.io.FileOutputStream(filename), Base64.ENCODE);
821 bos.write(dataToEncode);
822 success = true;
823 } // end try
824 catch (java.io.IOException e) {
825
826 success = false;
827 } // end catch: IOException
828 finally {
829 try {
830 bos.close();
831 } catch (Exception e) {
832 }
833 } // end finally
834
835 return success;
836 } // end encodeToFile
837
838
839 /**
840 * Convenience method for decoding data to a file.
841 *
842 * @param dataToDecode Base64-encoded data as a string
843 * @param filename Filename for saving decoded data
844 * @return <tt>true</tt> if successful, <tt>false</tt> otherwise
845 * @since 2.1
846 */
847 public static boolean decodeToFile(String dataToDecode, String filename) {
848 boolean success = false;
849 Base64.OutputStream bos = null;
850 try {
851 bos = new Base64.OutputStream(new java.io.FileOutputStream(filename), Base64.DECODE);
852 bos.write(dataToDecode.getBytes(PREFERRED_ENCODING));
853 success = true;
854 } // end try
855 catch (java.io.IOException e) {
856 success = false;
857 } // end catch: IOException
858 finally {
859 try {
860 bos.close();
861 } catch (Exception e) {
862 }
863 } // end finally
864
865 return success;
866 } // end decodeToFile
867
868
869 /**
870 * Convenience method for reading a base64-encoded
871 * file and decoding it.
872 *
873 * @param filename Filename for reading encoded data
874 * @return decoded byte array or null if unsuccessful
875 * @since 2.1
876 */
877 public static byte[] decodeFromFile(String filename) {
878 byte[] decodedData = null;
879 Base64.InputStream bis = null;
880 try {
881 // Set up some useful variables
882 java.io.File file = new java.io.File(filename);
883 byte[] buffer = null;
884 int length = 0;
885 int numBytes = 0;
886
887 // Check for size of file
888 if (file.length() > Integer.MAX_VALUE) {
889 System.err.println("File is too big for this convenience method (" + file.length() + " bytes).");
890 return null;
891 } // end if: file too big for int index
892 buffer = new byte[(int) file.length()];
893
894 // Open a stream
895 bis = new Base64.InputStream(new java.io.BufferedInputStream(new java.io.FileInputStream(file)), Base64.DECODE);
896
897 // Read until done
898 while ((numBytes = bis.read(buffer, length, 4096)) >= 0)
899 length += numBytes;
900
901 // Save in a variable to return
902 decodedData = new byte[length];
903 System.arraycopy(buffer, 0, decodedData, 0, length);
904
905 } // end try
906 catch (java.io.IOException e) {
907 System.err.println("Error decoding from file " + filename);
908 } // end catch: IOException
909 finally {
910 try {
911 bis.close();
912 } catch (Exception e) {
913 }
914 } // end finally
915
916 return decodedData;
917 } // end decodeFromFile
918
919
920 /**
921 * Convenience method for reading a binary file
922 * and base64-encoding it.
923 *
924 * @param filename Filename for reading binary data
925 * @return base64-encoded string or null if unsuccessful
926 * @since 2.1
927 */
928 public static String encodeFromFile(String filename) {
929 String encodedData = null;
930 Base64.InputStream bis = null;
931 try {
932 // Set up some useful variables
933 java.io.File file = new java.io.File(filename);
934 byte[] buffer = new byte[(int) (file.length() * 1.4)];
935 int length = 0;
936 int numBytes = 0;
937
938 // Open a stream
939 bis = new Base64.InputStream(new java.io.BufferedInputStream(new java.io.FileInputStream(file)), Base64.ENCODE);
940
941 // Read until done
942 while ((numBytes = bis.read(buffer, length, 4096)) >= 0)
943 length += numBytes;
944
945 // Save in a variable to return
946 encodedData = new String(buffer, 0, length, Base64.PREFERRED_ENCODING);
947
948 } // end try
949 catch (java.io.IOException e) {
950 System.err.println("Error encoding from file " + filename);
951 } // end catch: IOException
952 finally {
953 try {
954 bis.close();
955 } catch (Exception e) {
956 }
957 } // end finally
958
959 return encodedData;
960 } // end encodeFromFile
961
962
963
964
965 /* ******** I N N E R C L A S S I N P U T S T R E A M ******** */
966
967
968
969 /**
970 * A {@link Base64.InputStream} will read data from another
971 * <tt>java.io.InputStream</tt>, given in the constructor,
972 * and encode/decode to/from Base64 notation on the fly.
973 *
974 * @see Base64
975 * @since 1.3
976 */
977 public static class InputStream extends java.io.FilterInputStream {
978 private boolean encode; // Encoding or decoding
979 private int position; // Current position in the buffer
980 private byte[] buffer; // Small buffer holding converted data
981 private int bufferLength; // Length of buffer (3 or 4)
982 private int numSigBytes; // Number of meaningful bytes in the buffer
983 private int lineLength;
984 private boolean breakLines; // Break lines at less than 80 characters
985
986
987 /**
988 * Constructs a {@link Base64.InputStream} in DECODE mode.
989 *
990 * @param in the <tt>java.io.InputStream</tt> from which to read data.
991 * @since 1.3
992 */
993 public InputStream(java.io.InputStream in) {
994 this(in, DECODE);
995 } // end constructor
996
997
998 /**
999 * Constructs a {@link Base64.InputStream} in
1000 * either ENCODE or DECODE mode.
1001 * <p/>
1002 * Valid options:<pre>
1003 * ENCODE or DECODE: Encode or Decode as data is read.
1004 * DONT_BREAK_LINES: don't break lines at 76 characters
1005 * (only meaningful when encoding)
1006 * <i>Note: Technically, this makes your encoding non-compliant.</i>
1007 * </pre>
1008 * <p/>
1009 * Example: <code>new Base64.InputStream( in, Base64.DECODE )</code>
1010 *
1011 * @param in the <tt>java.io.InputStream</tt> from which to read data.
1012 * @param options Specified options
1013 * @see Base64#ENCODE
1014 * @see Base64#DECODE
1015 * @see Base64#DONT_BREAK_LINES
1016 * @since 2.0
1017 */
1018 public InputStream(java.io.InputStream in, int options) {
1019 super(in);
1020 this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES;
1021 this.encode = (options & ENCODE) == ENCODE;
1022 this.bufferLength = encode ? 4 : 3;
1023 this.buffer = new byte[bufferLength];
1024 this.position = -1;
1025 this.lineLength = 0;
1026 } // end constructor
1027
1028 /**
1029 * Reads enough of the input stream to convert
1030 * to/from Base64 and returns the next byte.
1031 *
1032 * @return next byte
1033 * @since 1.3
1034 */
1035 public int read() throws java.io.IOException {
1036 // Do we need to get data?
1037 if (position < 0) {
1038 if (encode) {
1039 byte[] b3 = new byte[3];
1040 int numBinaryBytes = 0;
1041 for (int i = 0; i < 3; i++) {
1042 try {
1043 int b = in.read();
1044
1045 // If end of stream, b is -1.
1046 if (b >= 0) {
1047 b3[i] = (byte) b;
1048 numBinaryBytes++;
1049 } // end if: not end of stream
1050
1051 } // end try: read
1052 catch (java.io.IOException e) {
1053 // Only a problem if we got no data at all.
1054 if (i == 0)
1055 throw e;
1056
1057 } // end catch
1058 } // end for: each needed input byte
1059
1060 if (numBinaryBytes > 0) {
1061 encode3to4(b3, 0, numBinaryBytes, buffer, 0);
1062 position = 0;
1063 numSigBytes = 4;
1064 } // end if: got data
1065 else {
1066 return -1;
1067 } // end else
1068 } // end if: encoding
1069
1070 // Else decoding
1071 else {
1072 byte[] b4 = new byte[4];
1073 int i = 0;
1074 for (i = 0; i < 4; i++) {
1075 // Read four "meaningful" bytes:
1076 int b = 0;
1077 do {
1078 b = in.read();
1079 } while (b >= 0 && DECODABET[b & 0x7f] <= WHITE_SPACE_ENC);
1080
1081 if (b < 0)
1082 break; // Reads a -1 if end of stream
1083
1084 b4[i] = (byte) b;
1085 } // end for: each needed input byte
1086
1087 if (i == 4) {
1088 numSigBytes = decode4to3(b4, 0, buffer, 0);
1089 position = 0;
1090 } // end if: got four characters
1091 else if (i == 0) {
1092 return -1;
1093 } // end else if: also padded correctly
1094 else {
1095 // Must have broken out from above.
1096 throw new java.io.IOException("Improperly padded Base64 input.");
1097 } // end
1098
1099 } // end else: decode
1100 } // end else: get data
1101
1102 // Got data?
1103 if (position >= 0) {
1104 // End of relevant data?
1105 if (/*!encode &&*/ position >= numSigBytes)
1106 return -1;
1107
1108 if (encode && breakLines && lineLength >= MAX_LINE_LENGTH) {
1109 lineLength = 0;
1110 return '\n';
1111 } // end if
1112 else {
1113 lineLength++; // This isn't important when decoding
1114 // but throwing an extra "if" seems
1115 // just as wasteful.
1116
1117 int b = buffer[position++];
1118
1119 if (position >= bufferLength)
1120 position = -1;
1121
1122 return b & 0xFF; // This is how you "cast" a byte that's
1123 // intended to be unsigned.
1124 } // end else
1125 } // end if: position >= 0
1126
1127 // Else error
1128 else {
1129 // When JDK1.4 is more accepted, use an assertion here.
1130 throw new java.io.IOException("Error in Base64 code reading stream.");
1131 } // end else
1132 } // end read
1133
1134
1135 /**
1136 * Calls {@link #read()} repeatedly until the end of stream
1137 * is reached or <var>len</var> bytes are read.
1138 * Returns number of bytes read into array or -1 if
1139 * end of stream is encountered.
1140 *
1141 * @param dest array to hold values
1142 * @param off offset for array
1143 * @param len max number of bytes to read into array
1144 * @return bytes read into array or -1 if end of stream is encountered.
1145 * @since 1.3
1146 */
1147 public int read(byte[] dest, int off, int len) throws java.io.IOException {
1148 int i;
1149 int b;
1150 for (i = 0; i < len; i++) {
1151 b = read();
1152
1153 //if( b < 0 && i == 0 )
1154 // return -1;
1155
1156 if (b >= 0)
1157 dest[off + i] = (byte) b;
1158 else if (i == 0)
1159 return -1;
1160 else
1161 break; // Out of 'for' loop
1162 } // end for: each byte read
1163 return i;
1164 } // end read
1165
1166 } // end inner class InputStream
1167
1168
1169
1170
1171
1172
1173 /* ******** I N N E R C L A S S O U T P U T S T R E A M ******** */
1174
1175
1176
1177 /**
1178 * A {@link Base64.OutputStream} will write data to another
1179 * <tt>java.io.OutputStream</tt>, given in the constructor,
1180 * and encode/decode to/from Base64 notation on the fly.
1181 *
1182 * @see Base64
1183 * @since 1.3
1184 */
1185 public static class OutputStream extends java.io.FilterOutputStream {
1186 private boolean encode;
1187 private int position;
1188 private byte[] buffer;
1189 private int bufferLength;
1190 private int lineLength;
1191 private boolean breakLines;
1192 private byte[] b4; // Scratch used in a few places
1193 private boolean suspendEncoding;
1194
1195 /**
1196 * Constructs a {@link Base64.OutputStream} in ENCODE mode.
1197 *
1198 * @param out the <tt>java.io.OutputStream</tt> to which data will be written.
1199 * @since 1.3
1200 */
1201 public OutputStream(java.io.OutputStream out) {
1202 this(out, ENCODE);
1203 } // end constructor
1204
1205
1206 /**
1207 * Constructs a {@link Base64.OutputStream} in
1208 * either ENCODE or DECODE mode.
1209 * <p/>
1210 * Valid options:<pre>
1211 * ENCODE or DECODE: Encode or Decode as data is read.
1212 * DONT_BREAK_LINES: don't break lines at 76 characters
1213 * (only meaningful when encoding)
1214 * <i>Note: Technically, this makes your encoding non-compliant.</i>
1215 * </pre>
1216 * <p/>
1217 * Example: <code>new Base64.OutputStream( out, Base64.ENCODE )</code>
1218 *
1219 * @param out the <tt>java.io.OutputStream</tt> to which data will be written.
1220 * @param options Specified options.
1221 * @see Base64#ENCODE
1222 * @see Base64#DECODE
1223 * @see Base64#DONT_BREAK_LINES
1224 * @since 1.3
1225 */
1226 public OutputStream(java.io.OutputStream out, int options) {
1227 super(out);
1228 this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES;
1229 this.encode = (options & ENCODE) == ENCODE;
1230 this.bufferLength = encode ? 3 : 4;
1231 this.buffer = new byte[bufferLength];
1232 this.position = 0;
1233 this.lineLength = 0;
1234 this.suspendEncoding = false;
1235 this.b4 = new byte[4];
1236 } // end constructor
1237
1238
1239 /**
1240 * Writes the byte to the output stream after
1241 * converting to/from Base64 notation.
1242 * When encoding, bytes are buffered three
1243 * at a time before the output stream actually
1244 * gets a write() call.
1245 * When decoding, bytes are buffered four
1246 * at a time.
1247 *
1248 * @param theByte the byte to write
1249 * @since 1.3
1250 */
1251 public void write(int theByte) throws java.io.IOException {
1252 // Encoding suspended?
1253 if (suspendEncoding) {
1254 super.out.write(theByte);
1255 return;
1256 } // end if: supsended
1257
1258 // Encode?
1259 if (encode) {
1260 buffer[position++] = (byte) theByte;
1261 if (position >= bufferLength) // Enough to encode.
1262 {
1263 out.write(encode3to4(b4, buffer, bufferLength));
1264
1265 lineLength += 4;
1266 if (breakLines && lineLength >= MAX_LINE_LENGTH) {
1267 out.write(NEW_LINE);
1268 lineLength = 0;
1269 } // end if: end of line
1270
1271 position = 0;
1272 } // end if: enough to output
1273 } // end if: encoding
1274
1275 // Else, Decoding
1276 else {
1277 // Meaningful Base64 character?
1278 if (DECODABET[theByte & 0x7f] > WHITE_SPACE_ENC) {
1279 buffer[position++] = (byte) theByte;
1280 if (position >= bufferLength) // Enough to output.
1281 {
1282 int len = Base64.decode4to3(buffer, 0, b4, 0);
1283 out.write(b4, 0, len);
1284 //out.write( Base64.decode4to3( buffer ) );
1285 position = 0;
1286 } // end if: enough to output
1287 } // end if: meaningful base64 character
1288 else if (DECODABET[theByte & 0x7f] != WHITE_SPACE_ENC) {
1289 throw new java.io.IOException("Invalid character in Base64 data.");
1290 } // end else: not white space either
1291 } // end else: decoding
1292 } // end write
1293
1294
1295 /**
1296 * Calls {@link #write(int)} repeatedly until <var>len</var>
1297 * bytes are written.
1298 *
1299 * @param theBytes array from which to read bytes
1300 * @param off offset for array
1301 * @param len max number of bytes to read into array
1302 * @since 1.3
1303 */
1304 public void write(byte[] theBytes, int off, int len) throws java.io.IOException {
1305 // Encoding suspended?
1306 if (suspendEncoding) {
1307 super.out.write(theBytes, off, len);
1308 return;
1309 } // end if: supsended
1310
1311 for (int i = 0; i < len; i++) {
1312 write(theBytes[off + i]);
1313 } // end for: each byte written
1314
1315 } // end write
1316
1317
1318 /**
1319 * Method added by PHIL. [Thanks, PHIL. -Rob]
1320 * This pads the buffer without closing the stream.
1321 */
1322 public void flushBase64() throws java.io.IOException {
1323 if (position > 0) {
1324 if (encode) {
1325 out.write(encode3to4(b4, buffer, position));
1326 position = 0;
1327 } // end if: encoding
1328 else {
1329 throw new java.io.IOException("Base64 input not properly padded.");
1330 } // end else: decoding
1331 } // end if: buffer partially full
1332
1333 } // end flush
1334
1335
1336 /**
1337 * Flushes and closes (I think, in the superclass) the stream.
1338 *
1339 * @since 1.3
1340 */
1341 public void close() throws java.io.IOException {
1342 // 1. Ensure that pending characters are written
1343 flushBase64();
1344
1345 // 2. Actually close the stream
1346 // Base class both flushes and closes.
1347 super.close();
1348
1349 buffer = null;
1350 out = null;
1351 } // end close
1352
1353
1354 /**
1355 * Suspends encoding of the stream.
1356 * May be helpful if you need to embed a piece of
1357 * base640-encoded data in a stream.
1358 *
1359 * @since 1.5.1
1360 */
1361 public void suspendEncoding() throws java.io.IOException {
1362 flushBase64();
1363 this.suspendEncoding = true;
1364 } // end suspendEncoding
1365
1366
1367 /**
1368 * Resumes encoding of the stream.
1369 * May be helpful if you need to embed a piece of
1370 * base640-encoded data in a stream.
1371 *
1372 * @since 1.5.1
1373 */
1374 public void resumeEncoding() {
1375 this.suspendEncoding = false;
1376 } // end resumeEncoding
1377
1378
1379 } // end inner class OutputStream
1380
1381
1382 } // end class Base64
1383