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1   /*
2    * $Id: Base64.java 19191 2010-08-25 21:05:23Z tcarlson $
3    * --------------------------------------------------------------------------------------
4    * Copyright (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
5    *
6    * The software in this package is published under the terms of the CPAL v1.0
7    * license, a copy of which has been included with this distribution in the
8    * LICENSE.txt file.
9    */
10  
11  /* 
12   * Encodes and decodes to and from Base64 notation.
13   *
14   * <p>
15   * Change Log:
16   * </p>
17   * <ul>
18   *  <li>current - cleaned up by Holger Hoffstaette (holger@codehaus.org) for Mule;
19   *  removed System.out/err printing and properly throw IOExceptions from all methods.
20   *  <li>v2.1 - Cleaned up javadoc comments and unused variables and methods. Added
21   *   some convenience methods for reading and writing to and from files.</li>
22   *  <li>v2.0.2 - Now specifies UTF-8 encoding in places where the code fails on systems
23   *   with other encodings (like EBCDIC).</li>
24   *  <li>v2.0.1 - Fixed an error when decoding a single byte, that is, when the
25   *   encoded data was a single byte.</li>
26   *  <li>v2.0 - I got rid of methods that used booleans to set options. 
27   *   Now everything is more consolidated and cleaner. The code now detects
28   *   when data that's being decoded is gzip-compressed and will decompress it
29   *   automatically. Generally things are cleaner. You'll probably have to
30   *   change some method calls that you were making to support the new
31   *   options format (<tt>int</tt>s that you "OR" together).</li>
32   *  <li>v1.5.1 - Fixed bug when decompressing and decoding to a             
33   *   byte[] using <tt>decode( String s, boolean gzipCompressed )</tt>.      
34   *   Added the ability to "suspend" encoding in the Output Stream so        
35   *   you can turn on and off the encoding if you need to embed base64       
36   *   data in an otherwise "normal" stream (like an XML file).</li>  
37   *  <li>v1.5 - Output stream pases on flush() command but doesn't do anything itself.
38   *      This helps when using GZIP streams.
39   *      Added the ability to GZip-compress objects before encoding them.</li>
40   *  <li>v1.4 - Added helper methods to read/write files.</li>
41   *  <li>v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.</li>
42   *  <li>v1.3.5 - Added flag to turn on and off line breaks. Fixed bug in input stream
43   *      where last buffer being read, if not completely full, was not returned.</li>
44   *  <li>v1.3.4 - Fixed when "improperly padded stream" error was thrown at the wrong time.</li>
45   *  <li>v1.3.3 - Fixed I/O streams which were totally messed up.</li>
46   * </ul>
47   *
48   * <p>
49   * I am placing this code in the Public Domain. Do with it as you will.
50   * This software comes with no guarantees or warranties but with
51   * plenty of well-wishing instead!
52   * Please visit <a href="http://iharder.net/base64">http://iharder.net/base64</a>
53   * periodically to check for updates or to contribute improvements.
54   * </p>
55   *
56   * @author Robert Harder
57   * @author rob@iharder.net
58   * @version 2.1
59   */
60  
61  package org.mule.util;
62  
63  import java.io.BufferedInputStream;
64  import java.io.ByteArrayInputStream;
65  import java.io.File;
66  import java.io.FileInputStream;
67  import java.io.FileOutputStream;
68  import java.io.FilterInputStream;
69  import java.io.FilterOutputStream;
70  import java.io.IOException;
71  import java.io.ObjectInputStream;
72  import java.io.ObjectOutputStream;
73  import java.io.Serializable;
74  import java.io.UnsupportedEncodingException;
75  import java.util.zip.GZIPInputStream;
76  import java.util.zip.GZIPOutputStream;
77  
78  import org.apache.commons.io.IOUtils;
79  import org.apache.commons.io.output.ByteArrayOutputStream;
80  
81  public final class Base64
82  {
83  
84      /* ******** P U B L I C F I E L D S ******** */
85  
86      /** No options specified. Value is zero. */
87      public static final int NO_OPTIONS = 0;
88  
89      /** Specify encoding. */
90      public static final int ENCODE = 1;
91  
92      /** Specify decoding. */
93      public static final int DECODE = 0;
94  
95      /** Specify that data should be gzip-compressed. */
96      public static final int GZIP = 2;
97  
98      /** Don't break lines when encoding (violates strict Base64 specification) */
99      public static final int DONT_BREAK_LINES = 8;
100 
101     /** Preferred encoding. */
102     public static final String PREFERRED_ENCODING = "UTF-8";
103 
104     /* ******** P R I V A T E F I E L D S ******** */
105 
106     /** Maximum line length (76) of Base64 output. */
107     private static final int MAX_LINE_LENGTH = 76;
108 
109     /** The equals sign (=) as a byte. */
110     private static final byte EQUALS_SIGN = (byte) '=';
111 
112     /** The new line character (\n) as a byte. */
113     private static final byte NEW_LINE = (byte) '\n';
114 
115     /** The 64 valid Base64 values. */
116     private static final byte[] ALPHABET;
117 
118     private static final byte[] NATIVE_ALPHABET =
119     /* May be something funny like EBCDIC */
120     {
121         (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G', (byte) 'H', (byte) 'I',
122         (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R',
123         (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) 'a',
124         (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j',
125         (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's',
126         (byte) 't', (byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z', (byte) '0', (byte) '1',
127         (byte) '2', (byte) '3', (byte) '4', (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '+',
128         (byte) '/'
129     };
130 
131     /** Determine which ALPHABET to use. */
132     static
133     {
134         byte[] bytes;
135         try
136         {
137             bytes = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".getBytes(PREFERRED_ENCODING);
138         } // end try
139         catch (java.io.UnsupportedEncodingException use)
140         {
141             bytes = NATIVE_ALPHABET; // Fall back to native encoding
142         } // end catch
143         ALPHABET = bytes;
144     } // end static
145 
146     /**
147      * Translates a Base64 value to either its 6-bit reconstruction value or a
148      * negative number indicating some other meaning.
149      */
150     private static final byte[] DECODABET = {-9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal
151         // 0 -
152         // 8
153         -5, -5, // Whitespace: Tab and Linefeed
154         -9, -9, // Decimal 11 - 12
155         -5, // Whitespace: Carriage Return
156         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
157         -9, -9, -9, -9, -9, // Decimal 27 - 31
158         -5, // Whitespace: Space
159         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
160         62, // Plus sign at decimal 43
161         -9, -9, -9, // Decimal 44 - 46
162         63, // Slash at decimal 47
163         52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
164         -9, -9, -9, // Decimal 58 - 60
165         -1, // Equals sign at decimal 61
166         -9, -9, -9, // Decimal 62 - 64
167         0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through 'N'
168         14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' through 'Z'
169         -9, -9, -9, -9, -9, -9, // Decimal 91 - 96
170         26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' through
171                                                             // 'm'
172         39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' through
173                                                             // 'z'
174         -9, -9, -9, -9 // Decimal 123 - 126
175     /*
176      * ,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 127 - 139
177      * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 140 - 152
178      * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 153 - 165
179      * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 166 - 178
180      * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 179 - 191
181      * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 192 - 204
182      * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 205 - 217
183      * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 218 - 230
184      * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 231 - 243
185      * -9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9 // Decimal 244 - 255
186      */
187     };
188 
189     // I think I end up not using the BAD_ENCODING indicator.
190     // private static final byte BAD_ENCODING = -9; // Indicates error in
191     // encoding
192     private static final byte WHITE_SPACE_ENC = -5; // Indicates white space in
193     // encoding
194     private static final byte EQUALS_SIGN_ENC = -1; // Indicates equals sign in
195 
196     // encoding
197 
198     /** Defeats instantiation. */
199     private Base64()
200     {
201         super();
202     }
203 
204     /* ******** E N C O D I N G M E T H O D S ******** */
205 
206     /**
207      * Encodes up to the first three bytes of array <var>threeBytes</var> and
208      * returns a four-byte array in Base64 notation. The actual number of significant
209      * bytes in your array is given by <var>numSigBytes</var>. The array
210      * <var>threeBytes</var> needs only be as big as <var>numSigBytes</var>. Code
211      * can reuse a byte array by passing a four-byte array as <var>b4</var>.
212      * 
213      * @param b4 A reusable byte array to reduce array instantiation
214      * @param threeBytes the array to convert
215      * @param numSigBytes the number of significant bytes in your array
216      * @return four byte array in Base64 notation.
217      * @since 1.5.1
218      */
219     private static byte[] encode3to4(byte[] b4, byte[] threeBytes, int numSigBytes)
220     {
221         encode3to4(threeBytes, 0, numSigBytes, b4, 0);
222         return b4;
223     } // end encode3to4
224 
225     /**
226      * Encodes up to three bytes of the array <var>source</var> and writes the
227      * resulting four Base64 bytes to <var>destination</var>. The source and
228      * destination arrays can be manipulated anywhere along their length by
229      * specifying <var>srcOffset</var> and <var>destOffset</var>. This method does
230      * not check to make sure your arrays are large enough to accomodate
231      * <var>srcOffset</var> + 3 for the <var>source</var> array or <var>destOffset</var> +
232      * 4 for the <var>destination</var> array. The actual number of significant
233      * bytes in your array is given by <var>numSigBytes</var>.
234      * 
235      * @param source the array to convert
236      * @param srcOffset the index where conversion begins
237      * @param numSigBytes the number of significant bytes in your array
238      * @param destination the array to hold the conversion
239      * @param destOffset the index where output will be put
240      * @return the <var>destination</var> array
241      * @since 1.3
242      */
243     private static byte[] encode3to4(byte[] source,
244                                      int srcOffset,
245                                      int numSigBytes,
246                                      byte[] destination,
247                                      int destOffset)
248     {
249         // 1 2 3
250         // 01234567890123456789012345678901 Bit position
251         // --------000000001111111122222222 Array position from threeBytes
252         // --------| || || || | Six bit groups to index ALPHABET
253         // >>18 >>12 >> 6 >> 0 Right shift necessary
254         // 0x3f 0x3f 0x3f Additional AND
255 
256         // Create buffer with zero-padding if there are only one or two
257         // significant bytes passed in the array.
258         // We have to shift left 24 in order to flush out the 1's that appear
259         // when Java treats a value as negative that is cast from a byte to an
260         // int.
261         int inBuff = (numSigBytes > 0 ? ((source[srcOffset] << 24) >>> 8) : 0)
262                      | (numSigBytes > 1 ? ((source[srcOffset + 1] << 24) >>> 16) : 0)
263                      | (numSigBytes > 2 ? ((source[srcOffset + 2] << 24) >>> 24) : 0);
264 
265         switch (numSigBytes)
266         {
267             case 3 :
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] = ALPHABET[(inBuff) & 0x3f];
272                 return destination;
273 
274             case 2 :
275                 destination[destOffset] = ALPHABET[(inBuff >>> 18)];
276                 destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
277                 destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
278                 destination[destOffset + 3] = EQUALS_SIGN;
279                 return destination;
280 
281             case 1 :
282                 destination[destOffset] = ALPHABET[(inBuff >>> 18)];
283                 destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
284                 destination[destOffset + 2] = EQUALS_SIGN;
285                 destination[destOffset + 3] = EQUALS_SIGN;
286                 return destination;
287 
288             default :
289                 return destination;
290         } // end switch
291     } // end encode3to4
292 
293     /**
294      * Serializes an object and returns the Base64-encoded version of that serialized
295      * object. If the object cannot be serialized or there is another error, the
296      * method will return <tt>null</tt>. The object is not GZip-compressed before
297      * being encoded.
298      * 
299      * @param serializableObject The object to encode
300      * @return The Base64-encoded object
301      * @since 1.4
302      */
303     public static String encodeObject(Serializable serializableObject) throws IOException
304     {
305         return encodeObject(serializableObject, NO_OPTIONS);
306     } // end encodeObject
307 
308     /**
309      * Serializes an object and returns the Base64-encoded version of that serialized
310      * object. If the object cannot be serialized or there is another error, the
311      * method will return <tt>null</tt>.
312      * <p>
313      * Valid options:
314      * 
315      * <pre>
316      *              GZIP: gzip-compresses object before encoding it.
317      *              DONT_BREAK_LINES: don't break lines at 76 characters
318      *                &lt;i&gt;Note: Technically, this makes your encoding non-compliant.&lt;/i&gt;
319      * </pre>
320      * 
321      * <p>
322      * Example: <code>encodeObject( myObj, Base64.GZIP )</code> or
323      * <p>
324      * Example:
325      * <code>encodeObject( myObj, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
326      * 
327      * @param serializableObject The object to encode
328      * @param options Specified options
329      * @return The Base64-encoded object
330      * @see Base64#GZIP
331      * @see Base64#DONT_BREAK_LINES
332      * @since 2.0
333      */
334     public static String encodeObject(Serializable serializableObject, int options) throws IOException
335     {
336         // Streams
337         ByteArrayOutputStream baos = null;
338         OutputStream b64os = null;
339         ObjectOutputStream oos = null;
340         GZIPOutputStream gzos = null;
341 
342         // Isolate options
343         int gzip = (options & GZIP);
344         int dontBreakLines = (options & DONT_BREAK_LINES);
345 
346         try
347         {
348             // ObjectOutputStream -> (GZIP) -> Base64 -> ByteArrayOutputStream
349             baos = new ByteArrayOutputStream(4096);
350             b64os = new Base64.OutputStream(baos, ENCODE | dontBreakLines);
351 
352             // GZip?
353             if (gzip == GZIP)
354             {
355                 gzos = new GZIPOutputStream(b64os);
356                 oos = new ObjectOutputStream(gzos);
357             } // end if: gzip
358             else
359             {
360                 oos = new ObjectOutputStream(b64os);
361             }
362 
363             oos.writeObject(serializableObject);
364 
365             if (gzos != null)
366             {
367                 gzos.finish();
368                 gzos.close();
369             }
370 
371             oos.close();
372         } // end try
373         catch (IOException e)
374         {
375             return null;
376         } // end catch
377         finally
378         {
379             IOUtils.closeQuietly(oos);
380             IOUtils.closeQuietly(gzos);
381             IOUtils.closeQuietly(b64os);
382             IOUtils.closeQuietly(baos);
383         } // end finally
384 
385         // Return value according to relevant encoding.
386         try
387         {
388             return new String(baos.toByteArray(), PREFERRED_ENCODING);
389         } // end try
390         catch (UnsupportedEncodingException uue)
391         {
392             return new String(baos.toByteArray());
393         } // end catch
394 
395     } // end encode
396 
397     /**
398      * Encodes a byte array into Base64 notation. Does not GZip-compress data.
399      * 
400      * @param source The data to convert
401      * @since 1.4
402      */
403     public static String encodeBytes(byte[] source) throws IOException
404     {
405         return encodeBytes(source, 0, source.length, NO_OPTIONS);
406     } // end encodeBytes
407 
408     /**
409      * Encodes a byte array into Base64 notation.
410      * <p>
411      * Valid options:
412      * 
413      * <pre>
414      *               GZIP: gzip-compresses object before encoding it.
415      *               DONT_BREAK_LINES: don't break lines at 76 characters
416      *                 &lt;i&gt;Note: Technically, this makes your encoding non-compliant.&lt;/i&gt;
417      * </pre>
418      * 
419      * <p>
420      * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
421      * <p>
422      * Example:
423      * <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
424      * 
425      * @param source The data to convert
426      * @param options Specified options
427      * @see Base64#GZIP
428      * @see Base64#DONT_BREAK_LINES
429      * @since 2.0
430      */
431     public static String encodeBytes(byte[] source, int options) throws IOException
432     {
433         return encodeBytes(source, 0, source.length, options);
434     } // end encodeBytes
435 
436     /**
437      * Encodes a byte array into Base64 notation. Does not GZip-compress data.
438      * 
439      * @param source The data to convert
440      * @param off Offset in array where conversion should begin
441      * @param len Length of data to convert
442      * @since 1.4
443      */
444     public static String encodeBytes(byte[] source, int off, int len) throws IOException
445     {
446         return encodeBytes(source, off, len, NO_OPTIONS);
447     } // end encodeBytes
448 
449     /**
450      * Encodes a byte array into Base64 notation.
451      * <p>
452      * Valid options:
453      * 
454      * <pre>
455      *              GZIP: gzip-compresses object before encoding it.
456      *              DONT_BREAK_LINES: don't break lines at 76 characters
457      *                &lt;i&gt;Note: Technically, this makes your encoding non-compliant.&lt;/i&gt;
458      * </pre>
459      * 
460      * <p>
461      * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
462      * <p>
463      * Example:
464      * <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
465      * 
466      * @param source The data to convert
467      * @param off Offset in array where conversion should begin
468      * @param len Length of data to convert
469      * @param options Specified options
470      * @see Base64#GZIP
471      * @see Base64#DONT_BREAK_LINES
472      * @since 2.0
473      */
474     public static String encodeBytes(byte[] source, int off, int len, int options) throws IOException
475     {
476         // Isolate options
477         int dontBreakLines = (options & DONT_BREAK_LINES);
478         int gzip = (options & GZIP);
479 
480         // Compress?
481         if (gzip == GZIP)
482         {
483             ByteArrayOutputStream baos = null;
484             GZIPOutputStream gzos = null;
485             Base64.OutputStream b64os = null;
486 
487             try
488             {
489                 // GZip -> Base64 -> ByteArray
490                 baos = new ByteArrayOutputStream(4096);
491                 b64os = new Base64.OutputStream(baos, ENCODE | dontBreakLines);
492                 gzos = new GZIPOutputStream(b64os);
493 
494                 gzos.write(source, off, len);
495                 gzos.finish();
496                 gzos.close();
497             } // end try
498             catch (IOException e)
499             {
500                 throw e;
501             } // end catch
502             finally
503             {
504                 IOUtils.closeQuietly(gzos);
505                 IOUtils.closeQuietly(b64os);
506                 IOUtils.closeQuietly(baos);
507             } // end finally
508 
509             // Return value according to relevant encoding.
510             try
511             {
512                 return new String(baos.toByteArray(), PREFERRED_ENCODING);
513             } // end try
514             catch (UnsupportedEncodingException uue)
515             {
516                 return new String(baos.toByteArray());
517             } // end catch
518         } // end if: compress
519 
520         // Else, don't compress. Better not to use streams at all then.
521         else
522         {
523             // Convert option to boolean in way that code likes it.
524             boolean breakLines = dontBreakLines == 0;
525 
526             int len43 = len * 4 / 3;
527             byte[] outBuff = new byte[(len43) // Main 4:3
528                                       + ((len % 3) > 0 ? 4 : 0) // Account for
529                                                                 // padding
530                                       + (breakLines ? (len43 / MAX_LINE_LENGTH) : 0)]; // New
531                                                                                         // lines
532 
533             int d = 0;
534             int e = 0;
535             int len2 = len - 2;
536             int lineLength = 0;
537             for (; d < len2; d += 3, e += 4)
538             {
539                 encode3to4(source, d + off, 3, outBuff, e);
540 
541                 lineLength += 4;
542                 if (breakLines && lineLength == MAX_LINE_LENGTH)
543                 {
544                     outBuff[e + 4] = NEW_LINE;
545                     e++;
546                     lineLength = 0;
547                 } // end if: end of line
548             } // en dfor: each piece of array
549 
550             if (d < len)
551             {
552                 encode3to4(source, d + off, len - d, outBuff, e);
553                 e += 4;
554             } // end if: some padding needed
555 
556             // Return value according to relevant encoding.
557             try
558             {
559                 return new String(outBuff, 0, e, PREFERRED_ENCODING);
560             } // end try
561             catch (UnsupportedEncodingException uue)
562             {
563                 return new String(outBuff, 0, e);
564             } // end catch
565 
566         } // end else: don't compress
567 
568     } // end encodeBytes
569 
570     /* ******** D E C O D I N G M E T H O D S ******** */
571 
572     /**
573      * Decodes four bytes from array <var>source</var> and writes the resulting
574      * bytes (up to three of them) to <var>destination</var>. The source and
575      * destination arrays can be manipulated anywhere along their length by
576      * specifying <var>srcOffset</var> and <var>destOffset</var>. This method does
577      * not check to make sure your arrays are large enough to accomodate
578      * <var>srcOffset</var> + 4 for the <var>source</var> array or <var>destOffset</var> +
579      * 3 for the <var>destination</var> array. This method returns the actual number
580      * of bytes that were converted from the Base64 encoding.
581      * 
582      * @param source the array to convert
583      * @param srcOffset the index where conversion begins
584      * @param destination the array to hold the conversion
585      * @param destOffset the index where output will be put
586      * @return the number of decoded bytes converted
587      * @since 1.3
588      */
589     private static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset)
590     {
591         // Example: Dk==
592         if (source[srcOffset + 2] == EQUALS_SIGN)
593         {
594             // Two ways to do the same thing. Don't know which way I like best.
595             // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6
596             // )
597             // | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 );
598             int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
599                           | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12);
600 
601             destination[destOffset] = (byte) (outBuff >>> 16);
602             return 1;
603         }
604 
605         // Example: DkL=
606         else if (source[srcOffset + 3] == EQUALS_SIGN)
607         {
608             // Two ways to do the same thing. Don't know which way I like best.
609             // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6
610             // )
611             // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
612             // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 );
613             int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
614                           | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
615                           | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6);
616 
617             destination[destOffset] = (byte) (outBuff >>> 16);
618             destination[destOffset + 1] = (byte) (outBuff >>> 8);
619             return 2;
620         }
621 
622         // Example: DkLE
623         else
624         {
625             try
626             {
627                 // Two ways to do the same thing. Don't know which way I like
628                 // best.
629                 // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 )
630                 // >>> 6 )
631                 // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
632                 // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 )
633                 // | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 );
634                 int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
635                               | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
636                               | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6)
637                               | ((DECODABET[source[srcOffset + 3]] & 0xFF));
638 
639                 destination[destOffset] = (byte) (outBuff >> 16);
640                 destination[destOffset + 1] = (byte) (outBuff >> 8);
641                 destination[destOffset + 2] = (byte) (outBuff);
642 
643                 return 3;
644             }
645             catch (Exception e)
646             {
647                 // this is not good.
648                 StringBuffer msg = new StringBuffer(64);
649                 msg.append(source[srcOffset]).append(": ").append(DECODABET[source[srcOffset]]);
650                 msg.append(source[srcOffset + 1]).append(": ").append(DECODABET[source[srcOffset + 1]]);
651                 msg.append(source[srcOffset + 2]).append(": ").append(DECODABET[source[srcOffset + 2]]);
652                 msg.append(source[srcOffset + 3]).append(": ").append(DECODABET[source[srcOffset + 3]]);
653                 throw (IllegalStateException) new IllegalStateException(msg.toString()).initCause(e);
654             } // end catch
655         }
656     } // end decodeToBytes
657 
658     /**
659      * Very low-level access to decoding ASCII characters in the form of a byte
660      * array. Does not support automatically gunzipping or any other "fancy"
661      * features.
662      * 
663      * @param source The Base64 encoded data
664      * @param off The offset of where to begin decoding
665      * @param len The length of characters to decode
666      * @return decoded data
667      * @since 1.3
668      */
669     public static byte[] decode(byte[] source, int off, int len)
670     {
671         int len34 = len * 3 / 4;
672         byte[] outBuff = new byte[len34]; // Upper limit on size of output
673         int outBuffPosn = 0;
674 
675         byte[] b4 = new byte[4];
676         int b4Posn = 0;
677         int i = 0;
678         byte sbiCrop = 0;
679         byte sbiDecode = 0;
680         for (i = off; i < off + len; i++)
681         {
682             sbiCrop = (byte) (source[i] & 0x7f); // Only the low seven bits
683             sbiDecode = DECODABET[sbiCrop];
684 
685             if (sbiDecode >= WHITE_SPACE_ENC) // White space, Equals sign or
686             // better
687             {
688                 if (sbiDecode >= EQUALS_SIGN_ENC)
689                 {
690                     b4[b4Posn++] = sbiCrop;
691                     if (b4Posn > 3)
692                     {
693                         outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn);
694                         b4Posn = 0;
695 
696                         // If that was the equals sign, break out of 'for' loop
697                         if (sbiCrop == EQUALS_SIGN)
698                         {
699                             break;
700                         }
701                     } // end if: quartet built
702 
703                 } // end if: equals sign or better
704 
705             } // end if: white space, equals sign or better
706             else
707             {
708                 throw new IllegalArgumentException("Bad Base64 input character at " + i + ": " + source[i]
709                                 + "(decimal)");
710             } // end else:
711         } // each input character
712 
713         byte[] out = new byte[outBuffPosn];
714         System.arraycopy(outBuff, 0, out, 0, outBuffPosn);
715         return out;
716     } // end decode
717 
718     /**
719      * Decodes data from Base64 notation, automatically detecting gzip-compressed
720      * data and decompressing it.
721      * 
722      * @param s the string to decode
723      * @return the decoded data
724      * @since 1.4
725      */
726     public static byte[] decode(String s)
727     {
728         byte[] bytes;
729         try
730         {
731             bytes = s.getBytes(PREFERRED_ENCODING);
732         } // end try
733         catch (UnsupportedEncodingException uee)
734         {
735             bytes = s.getBytes();
736         } // end catch
737         // </change>
738 
739         // Decode
740         bytes = decode(bytes, 0, bytes.length);
741 
742         // Check to see if it's gzip-compressed
743         // GZIP Magic Two-Byte Number: 0x8b1f (35615)
744         if (bytes != null && bytes.length >= 4)
745         {
746 
747             int head = (bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00);
748             if (GZIPInputStream.GZIP_MAGIC == head)
749             {
750                 ByteArrayInputStream bais = null;
751                 GZIPInputStream gzis = null;
752                 ByteArrayOutputStream baos = null;
753                 byte[] buffer = new byte[4096];
754                 int length = 0;
755 
756                 try
757                 {
758                     baos = new ByteArrayOutputStream(4096);
759                     bais = new ByteArrayInputStream(bytes);
760                     gzis = new GZIPInputStream(bais);
761 
762                     while ((length = gzis.read(buffer)) >= 0)
763                     {
764                         baos.write(buffer, 0, length);
765                     } // end while: reading input
766 
767                     // No error? Get new bytes.
768                     bytes = baos.toByteArray();
769 
770                 } // end try
771                 catch (IOException e)
772                 {
773                     // Just return originally-decoded bytes
774                 } // end catch
775                 finally
776                 {
777                     IOUtils.closeQuietly(baos);
778                     IOUtils.closeQuietly(gzis);
779                     IOUtils.closeQuietly(bais);
780                 } // end finally
781 
782             } // end if: gzipped
783         } // end if: bytes.length >= 2
784 
785         return bytes;
786     } // end decode
787 
788     /**
789      * Attempts to decode Base64 data and deserialize a Java Object within. Returns
790      * <tt>null</tt> if there was an error.
791      * 
792      * @param encodedObject The Base64 data to decode
793      * @return The decoded and deserialized object
794      * @since 1.5
795      */
796     public static Object decodeToObject(String encodedObject) throws IOException, ClassNotFoundException
797     {
798         // Decode and gunzip if necessary
799         byte[] objBytes = decode(encodedObject);
800 
801         ByteArrayInputStream bais = null;
802         ObjectInputStream ois = null;
803         Object obj = null;
804 
805         try
806         {
807             bais = new ByteArrayInputStream(objBytes);
808             ois = new ObjectInputStream(bais);
809             obj = ois.readObject();
810         } // end try
811         catch (IOException e)
812         {
813             throw e;
814         } // end catch
815         catch (java.lang.ClassNotFoundException e)
816         {
817             throw e;
818         } // end catch
819         finally
820         {
821             IOUtils.closeQuietly(bais);
822             IOUtils.closeQuietly(ois);
823         } // end finally
824 
825         return obj;
826     } // end decodeObject
827 
828     /**
829      * Convenience method for encoding data to a file.
830      * 
831      * @param dataToEncode byte array of data to encode in base64 form
832      * @param filename Filename for saving encoded data
833      * @since 2.1
834      */
835     public static void encodeToFile(byte[] dataToEncode, String filename) throws IOException
836     {
837         Base64.OutputStream bos = null;
838 
839         try
840         {
841             bos = new Base64.OutputStream(new FileOutputStream(filename), Base64.ENCODE);
842             bos.write(dataToEncode);
843         } // end try
844         catch (IOException e)
845         {
846             throw e;
847         } // end catch: IOException
848         finally
849         {
850             IOUtils.closeQuietly(bos);
851         } // end finally
852     } // end encodeToFile
853 
854     /**
855      * Convenience method for decoding data to a file.
856      * 
857      * @param dataToDecode Base64-encoded data as a string
858      * @param filename Filename for saving decoded data
859      * @since 2.1
860      */
861     public static void decodeToFile(String dataToDecode, String filename) throws IOException
862     {
863         Base64.OutputStream bos = null;
864 
865         try
866         {
867             bos = new Base64.OutputStream(new FileOutputStream(filename), Base64.DECODE);
868             bos.write(dataToDecode.getBytes(PREFERRED_ENCODING));
869         } // end try
870         catch (IOException e)
871         {
872             throw e;
873         } // end catch: IOException
874         finally
875         {
876             IOUtils.closeQuietly(bos);
877         } // end finally
878     } // end decodeToFile
879 
880     /**
881      * Convenience method for reading a base64-encoded file and decoding it.
882      * 
883      * @param filename Filename for reading encoded data
884      * @return decoded byte array or null if unsuccessful
885      * @since 2.1
886      */
887     public static byte[] decodeFromFile(String filename) throws IOException
888     {
889         byte[] decodedData = null;
890         Base64.InputStream bis = null;
891 
892         try
893         {
894             // Set up some useful variables
895             File file = FileUtils.newFile(filename);
896             byte[] buffer = null;
897             int length = 0;
898             int numBytes = 0;
899 
900             // Check for size of file
901             if (file.length() > Integer.MAX_VALUE)
902             {
903                 throw new IllegalArgumentException("File is too big for this convenience method ("
904                                                    + file.length() + " bytes).");
905             } // end if: file too big for int index
906             buffer = new byte[(int) file.length()];
907 
908             // Open a stream
909             bis = new Base64.InputStream(new BufferedInputStream(new FileInputStream(file)), Base64.DECODE);
910 
911             // Read until done
912             while ((numBytes = bis.read(buffer, length, 4096)) >= 0)
913             {
914                 length += numBytes;
915             }
916 
917             // Save in a variable to return
918             decodedData = new byte[length];
919             System.arraycopy(buffer, 0, decodedData, 0, length);
920         } // end try
921         catch (IOException e)
922         {
923             throw e;
924         } // end catch: IOException
925         finally
926         {
927             IOUtils.closeQuietly(bis);
928         } // end finally
929 
930         return decodedData;
931     } // end decodeFromFile
932 
933     /**
934      * Convenience method for reading a binary file and base64-encoding it.
935      * 
936      * @param filename Filename for reading binary data
937      * @return base64-encoded string or null if unsuccessful
938      * @since 2.1
939      */
940     public static String encodeFromFile(String filename) throws IOException
941     {
942         String encodedData = null;
943         Base64.InputStream bis = null;
944 
945         try
946         {
947             // Set up some useful variables
948             File file = FileUtils.newFile(filename);
949             byte[] buffer = new byte[(int) (file.length() * 1.4)];
950             int length = 0;
951             int numBytes = 0;
952 
953             // Open a stream
954             bis = new Base64.InputStream(new BufferedInputStream(new FileInputStream(file)), Base64.ENCODE);
955 
956             // Read until done
957             while ((numBytes = bis.read(buffer, length, 4096)) >= 0)
958             {
959                 length += numBytes;
960             }
961 
962             // Save in a variable to return
963             encodedData = new String(buffer, 0, length, Base64.PREFERRED_ENCODING);
964         } // end try
965         catch (IOException e)
966         {
967             throw e;
968         } // end catch: IOException
969         finally
970         {
971             IOUtils.closeQuietly(bis);
972         } // end finally
973 
974         return encodedData;
975     } // end encodeFromFile
976 
977     /* ******** I N N E R C L A S S I N P U T S T R E A M ******** */
978 
979     /**
980      * A {@link Base64.InputStream} will read data from another <tt>InputStream</tt>,
981      * given in the constructor, and encode/decode to/from Base64 notation on the
982      * fly.
983      * 
984      * @see Base64
985      * @since 1.3
986      */
987     public static class InputStream extends FilterInputStream
988     {
989         private boolean encode; // Encoding or decoding
990         private int position; // Current position in the buffer
991         private byte[] buffer; // Small buffer holding converted data
992         private int bufferLength; // Length of buffer (3 or 4)
993         private int numSigBytes; // Number of meaningful bytes in the buffer
994         private int lineLength;
995         private boolean breakLines; // Break lines at less than 80 characters
996 
997         /**
998          * Constructs a {@link Base64.InputStream} in DECODE mode.
999          * 
1000          * @param in the <tt>InputStream</tt> from which to read data.
1001          * @since 1.3
1002          */
1003         public InputStream(java.io.InputStream in)
1004         {
1005             this(in, DECODE);
1006         } // end constructor
1007 
1008         /**
1009          * Constructs a {@link Base64.InputStream} in either ENCODE or DECODE mode.
1010          * <p>
1011          * Valid options:
1012          * 
1013          * <pre>
1014          *              ENCODE or DECODE: Encode or Decode as data is read.
1015          *              DONT_BREAK_LINES: don't break lines at 76 characters
1016          *                (only meaningful when encoding)
1017          *                &lt;i&gt;Note: Technically, this makes your encoding non-compliant.&lt;/i&gt;
1018          * </pre>
1019          * 
1020          * <p>
1021          * Example: <code>new Base64.InputStream( in, Base64.DECODE )</code>
1022          * 
1023          * @param in the <tt>InputStream</tt> from which to read data.
1024          * @param options Specified options
1025          * @see Base64#ENCODE
1026          * @see Base64#DECODE
1027          * @see Base64#DONT_BREAK_LINES
1028          * @since 2.0
1029          */
1030         public InputStream(java.io.InputStream in, int options)
1031         {
1032             super(in);
1033             this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES;
1034             this.encode = (options & ENCODE) == ENCODE;
1035             this.bufferLength = encode ? 4 : 3;
1036             this.buffer = new byte[bufferLength];
1037             this.position = -1;
1038             this.lineLength = 0;
1039         } // end constructor
1040 
1041         /**
1042          * Reads enough of the input stream to convert to/from Base64 and returns the
1043          * next byte.
1044          * 
1045          * @return next byte
1046          * @since 1.3
1047          */
1048         public int read() throws IOException
1049         {
1050             // Do we need to get data?
1051             if (position < 0)
1052             {
1053                 if (encode)
1054                 {
1055                     byte[] b3 = new byte[3];
1056                     int numBinaryBytes = 0;
1057                     for (int i = 0; i < 3; i++)
1058                     {
1059                         try
1060                         {
1061                             int b = in.read();
1062 
1063                             // If end of stream, b is -1.
1064                             if (b >= 0)
1065                             {
1066                                 b3[i] = (byte) b;
1067                                 numBinaryBytes++;
1068                             } // end if: not end of stream
1069 
1070                         } // end try: read
1071                         catch (IOException e)
1072                         {
1073                             // Only a problem if we got no data at all.
1074                             if (i == 0)
1075                             {
1076                                 throw e;
1077                             }
1078 
1079                         } // end catch
1080                     } // end for: each needed input byte
1081 
1082                     if (numBinaryBytes > 0)
1083                     {
1084                         encode3to4(b3, 0, numBinaryBytes, buffer, 0);
1085                         position = 0;
1086                         numSigBytes = 4;
1087                     } // end if: got data
1088                     else
1089                     {
1090                         return -1;
1091                     } // end else
1092                 } // end if: encoding
1093 
1094                 // Else decoding
1095                 else
1096                 {
1097                     byte[] b4 = new byte[4];
1098                     int i = 0;
1099                     for (i = 0; i < 4; i++)
1100                     {
1101                         // Read four "meaningful" bytes:
1102                         int b = 0;
1103                         do
1104                         {
1105                             b = in.read();
1106                         }
1107                         while (b >= 0 && DECODABET[b & 0x7f] <= WHITE_SPACE_ENC);
1108 
1109                         if (b < 0)
1110                         {
1111                             break; // Reads a -1 if end of stream
1112                         }
1113 
1114                         b4[i] = (byte) b;
1115                     } // end for: each needed input byte
1116 
1117                     if (i == 4)
1118                     {
1119                         numSigBytes = decode4to3(b4, 0, buffer, 0);
1120                         position = 0;
1121                     } // end if: got four characters
1122                     else if (i == 0)
1123                     {
1124                         return -1;
1125                     } // end else if: also padded correctly
1126                     else
1127                     {
1128                         // Must have broken out from above.
1129                         throw new IOException("Improperly padded Base64 input.");
1130                     } // end
1131 
1132                 } // end else: decode
1133             } // end else: get data
1134 
1135             // Got data?
1136             if (position >= 0)
1137             {
1138                 // End of relevant data?
1139                 if ( /* !encode && */position >= numSigBytes)
1140                 {
1141                     return -1;
1142                 }
1143 
1144                 if (encode && breakLines && lineLength >= MAX_LINE_LENGTH)
1145                 {
1146                     lineLength = 0;
1147                     return '\n';
1148                 } // end if
1149                 else
1150                 {
1151                     lineLength++; // This isn't important when decoding
1152                     // but throwing an extra "if" seems
1153                     // just as wasteful.
1154 
1155                     int b = buffer[position++];
1156 
1157                     if (position >= bufferLength)
1158                     {
1159                         position = -1;
1160                     }
1161 
1162                     return b & 0xFF; // This is how you "cast" a byte that's
1163                     // intended to be unsigned.
1164                 } // end else
1165             } // end if: position >= 0
1166 
1167             // Else error
1168             else
1169             {
1170                 // When JDK1.4 is more accepted, use an assertion here.
1171                 throw new IOException("Error in Base64 code reading stream.");
1172             } // end else
1173         } // end read
1174 
1175         /**
1176          * Calls {@link #read()} repeatedly until the end of stream is reached or
1177          * <var>len</var> bytes are read. Returns number of bytes read into array or
1178          * -1 if end of stream is encountered.
1179          * 
1180          * @param dest array to hold values
1181          * @param off offset for array
1182          * @param len max number of bytes to read into array
1183          * @return bytes read into array or -1 if end of stream is encountered.
1184          * @since 1.3
1185          */
1186         public int read(byte[] dest, int off, int len) throws IOException
1187         {
1188             int i;
1189             int b;
1190             for (i = 0; i < len; i++)
1191             {
1192                 b = read();
1193 
1194                 // if( b < 0 && i == 0 )
1195                 // return -1;
1196 
1197                 if (b >= 0)
1198                 {
1199                     dest[off + i] = (byte) b;
1200                 }
1201                 else if (i == 0)
1202                 {
1203                     return -1;
1204                 }
1205                 else
1206                 {
1207                     break; // Out of 'for' loop
1208                 }
1209             } // end for: each byte read
1210             return i;
1211         } // end read
1212 
1213     } // end inner class InputStream
1214 
1215     /* ******** I N N E R C L A S S O U T P U T S T R E A M ******** */
1216 
1217     /**
1218      * A {@link Base64.OutputStream} will write data to another <tt>OutputStream</tt>,
1219      * given in the constructor, and encode/decode to/from Base64 notation on the
1220      * fly.
1221      * 
1222      * @see Base64
1223      * @since 1.3
1224      */
1225     public static class OutputStream extends FilterOutputStream
1226     {
1227         private boolean encode;
1228         private int position;
1229         private byte[] buffer;
1230         private int bufferLength;
1231         private int lineLength;
1232         private boolean breakLines;
1233         private byte[] b4; // Scratch used in a few places
1234         private boolean suspendEncoding;
1235 
1236         /**
1237          * Constructs a {@link Base64.OutputStream} in ENCODE mode.
1238          * 
1239          * @param out the <tt>OutputStream</tt> to which data will be written.
1240          * @since 1.3
1241          */
1242         public OutputStream(java.io.OutputStream out)
1243         {
1244             this(out, ENCODE);
1245         } // end constructor
1246 
1247         /**
1248          * Constructs a {@link Base64.OutputStream} in either ENCODE or DECODE mode.
1249          * <p>
1250          * Valid options:
1251          * 
1252          * <pre>
1253          *              ENCODE or DECODE: Encode or Decode as data is read.
1254          *              DONT_BREAK_LINES: don't break lines at 76 characters
1255          *                (only meaningful when encoding)
1256          *                &lt;i&gt;Note: Technically, this makes your encoding non-compliant.&lt;/i&gt;
1257          * </pre>
1258          * 
1259          * <p>
1260          * Example: <code>new Base64.OutputStream( out, Base64.ENCODE )</code>
1261          * 
1262          * @param out the <tt>OutputStream</tt> to which data will be written.
1263          * @param options Specified options.
1264          * @see Base64#ENCODE
1265          * @see Base64#DECODE
1266          * @see Base64#DONT_BREAK_LINES
1267          * @since 1.3
1268          */
1269         public OutputStream(java.io.OutputStream out, int options)
1270         {
1271             super(out);
1272             this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES;
1273             this.encode = (options & ENCODE) == ENCODE;
1274             this.bufferLength = encode ? 3 : 4;
1275             this.buffer = new byte[bufferLength];
1276             this.position = 0;
1277             this.lineLength = 0;
1278             this.suspendEncoding = false;
1279             this.b4 = new byte[4];
1280         } // end constructor
1281 
1282         /**
1283          * Writes the byte to the output stream after converting to/from Base64
1284          * notation. When encoding, bytes are buffered three at a time before the
1285          * output stream actually gets a write() call. When decoding, bytes are
1286          * buffered four at a time.
1287          * 
1288          * @param theByte the byte to write
1289          * @since 1.3
1290          */
1291         public void write(int theByte) throws IOException
1292         {
1293             // Encoding suspended?
1294             if (suspendEncoding)
1295             {
1296                 super.out.write(theByte);
1297                 return;
1298             } // end if: supsended
1299 
1300             // Encode?
1301             if (encode)
1302             {
1303                 buffer[position++] = (byte) theByte;
1304                 if (position >= bufferLength) // Enough to encode.
1305                 {
1306                     out.write(encode3to4(b4, buffer, bufferLength));
1307 
1308                     lineLength += 4;
1309                     if (breakLines && lineLength >= MAX_LINE_LENGTH)
1310                     {
1311                         out.write(NEW_LINE);
1312                         lineLength = 0;
1313                     } // end if: end of line
1314 
1315                     position = 0;
1316                 } // end if: enough to output
1317             } // end if: encoding
1318 
1319             // Else, Decoding
1320             else
1321             {
1322                 // Meaningful Base64 character?
1323                 if (DECODABET[theByte & 0x7f] > WHITE_SPACE_ENC)
1324                 {
1325                     buffer[position++] = (byte) theByte;
1326                     if (position >= bufferLength) // Enough to output.
1327                     {
1328                         int len = Base64.decode4to3(buffer, 0, b4, 0);
1329                         out.write(b4, 0, len);
1330                         // out.write( Base64.decode4to3( buffer ) );
1331                         position = 0;
1332                     } // end if: enough to output
1333                 } // end if: meaningful base64 character
1334                 else if (DECODABET[theByte & 0x7f] != WHITE_SPACE_ENC)
1335                 {
1336                     throw new IOException("Invalid character in Base64 data.");
1337                 } // end else: not white space either
1338             } // end else: decoding
1339         } // end write
1340 
1341         /**
1342          * Calls {@link #write(int)} repeatedly until <var>len</var> bytes are
1343          * written.
1344          * 
1345          * @param theBytes array from which to read bytes
1346          * @param off offset for array
1347          * @param len max number of bytes to read into array
1348          * @since 1.3
1349          */
1350         public void write(byte[] theBytes, int off, int len) throws IOException
1351         {
1352             // Encoding suspended?
1353             if (suspendEncoding)
1354             {
1355                 super.out.write(theBytes, off, len);
1356                 return;
1357             } // end if: supsended
1358 
1359             for (int i = 0; i < len; i++)
1360             {
1361                 write(theBytes[off + i]);
1362             } // end for: each byte written
1363 
1364         } // end write
1365 
1366         /**
1367          * Method added by PHIL. [Thanks, PHIL. -Rob] This pads the buffer without
1368          * closing the stream.
1369          */
1370         public void flushBase64() throws IOException
1371         {
1372             if (position > 0)
1373             {
1374                 if (encode)
1375                 {
1376                     out.write(encode3to4(b4, buffer, position));
1377                     position = 0;
1378                 } // end if: encoding
1379                 else
1380                 {
1381                     throw new IOException("Base64 input not properly padded.");
1382                 } // end else: decoding
1383             } // end if: buffer partially full
1384 
1385         } // end flush
1386 
1387         /**
1388          * Flushes and closes (I think, in the superclass) the stream.
1389          * 
1390          * @since 1.3
1391          */
1392         public void close() throws IOException
1393         {
1394             // 1. Ensure that pending characters are written
1395             flushBase64();
1396 
1397             // 2. Actually close the stream
1398             // Base class both flushes and closes.
1399             super.close();
1400 
1401             buffer = null;
1402             out = null;
1403         } // end close
1404 
1405         /**
1406          * Suspends encoding of the stream. May be helpful if you need to embed a
1407          * piece of base640-encoded data in a stream.
1408          * 
1409          * @since 1.5.1
1410          */
1411         public void suspendEncoding() throws IOException
1412         {
1413             flushBase64();
1414             this.suspendEncoding = true;
1415         } // end suspendEncoding
1416 
1417         /**
1418          * Resumes encoding of the stream. May be helpful if you need to embed a
1419          * piece of base640-encoded data in a stream.
1420          * 
1421          * @since 1.5.1
1422          */
1423         public void resumeEncoding()
1424         {
1425             this.suspendEncoding = false;
1426         } // end resumeEncoding
1427 
1428     } // end inner class OutputStream
1429 
1430 } // end class Base64