/*
    * ModeShape (http://www.modeshape.org)
    * See the COPYRIGHT.txt file distributed with this work for information
    * regarding copyright ownership.  Some portions may be licensed
    * to Red Hat, Inc. under one or more contributor license agreements.
    * See the AUTHORS.txt file in the distribution for a full listing of 
    * individual contributors. 
    *
    * ModeShape is free software. Unless otherwise indicated, all code in ModeShape
   * is licensed to you under the terms of the GNU Lesser General Public License as
   * published by the Free Software Foundation; either version 2.1 of
   * the License, or (at your option) any later version.
   *
   * ModeShape is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this software; if not, write to the Free
   * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
   * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
   */
  package org.modeshape.common.util;
  
  import java.io.BufferedInputStream;
  import java.io.IOException;
  import org.modeshape.common.SystemFailureException;
  
  /**
   * <p>
   * Encodes and decodes to and from Base64 notation.
   * </p>
   * <p>
   * Homepage: <a href="http://iharder.net/base64">http://iharder.net/base64</a>.
   * </p>
   * <p>
   * Example:
   * </p>
   * <code>String encoded = Base64.encode( myByteArray );</code> <br /> <code>byte[] myByteArray = Base64.decode( encoded );</code>
   * <p>
   * The <tt>options</tt> parameter, which appears in a few places, is used to pass several pieces of information to the encoder. In
   * the "higher level" methods such as encodeBytes( bytes, options ) the options parameter can be used to indicate such things as
   * first gzipping the bytes before encoding them, not inserting linefeeds, and encoding using the URL-safe and Ordered dialects.
   * </p>
   * <p>
   * Note, according to <a href="http://www.faqs.org/rfcs/rfc3548.html">RFC3548</a>, Section 2.1, implementations should not add
   * line feeds unless explicitly told to do so. I've got Base64 set to this behavior now, although earlier versions broke lines by
   * default.
   * </p>
   * <p>
   * The constants defined in Base64 can be OR-ed together to combine options, so you might make a call like this:
   * </p>
   * <code>String encoded = Base64.encodeBytes( mybytes, Base64.GZIP | Base64.DO_BREAK_LINES );</code>
   * <p>
   * to compress the data before encoding it and then making the output have newline characters.
   * </p>
   * <p>
   * Also...
   * </p>
   * <code>String encoded = Base64.encodeBytes( crazyString.getBytes() );</code>
   * <p>
   * Change Log:
   * </p>
   * <ul>
   * <li>v2.3.7 - Fixed subtle bug when base 64 input stream contained the value 01111111, which is an invalid base 64 character but
   * should not throw an ArrayIndexOutOfBoundsException either. Led to discovery of mishandling (or potential for better handling)
   * of other bad input characters. You should now get an IOException if you try decoding something that has bad characters in it.</li>
   * <li>v2.3.6 - Fixed bug when breaking lines and the final byte of the encoded string ended in the last column; the buffer was
   * not properly shrunk and contained an extra (null) byte that made it into the string.</li>
   * <li>v2.3.5 - Fixed bug in {@link #encodeFromFile} where estimated buffer size was wrong for files of size 31, 34, and 37 bytes.
   * </li>
   * <li>v2.3.4 - Fixed bug when working with gzipped streams whereby flushing the Base64.OutputStream closed the Base64 encoding
   * (by padding with equals signs) too soon. Also added an option to suppress the automatic decoding of gzipped streams. Also added
   * experimental support for specifying a class loader when using the
   * {@link #decodeToObject(java.lang.String, int, java.lang.ClassLoader)} method.</li>
   * <li>v2.3.3 - Changed default char encoding to US-ASCII which reduces the internal Java footprint with its CharEncoders and so
   * forth. Fixed some javadocs that were inconsistent. Removed imports and specified things like java.io.IOException explicitly
   * inline.</li>
   * <li>v2.3.2 - Reduced memory footprint! Finally refined the "guessing" of how big the final encoded data will be so that the
   * code doesn't have to create two output arrays: an oversized initial one and then a final, exact-sized one. Big win when using
   * the {@link #encodeBytesToBytes(byte[])} family of methods (and not using the gzip options which uses a different mechanism with
   * streams and stuff).</li>
   * <li>v2.3.1 - Added {@link #encodeBytesToBytes(byte[], int, int, int)} and some similar helper methods to be more efficient with
   * memory by not returning a String but just a byte array.</li>
   * <li>v2.3 - <strong>This is not a drop-in replacement!</strong> This is two years of comments and bug fixes queued up and
   * finally executed. Thanks to everyone who sent me stuff, and I'm sorry I wasn't able to distribute your fixes to everyone else.
   * Much bad coding was cleaned up including throwing exceptions where necessary instead of returning null values or something
   * similar. Here are some changes that may affect you:
   * <ul>
   * <li><em>Does not break lines, by default.</em> This is to keep in compliance with <a
   * href="http://www.faqs.org/rfcs/rfc3548.html">RFC3548</a>.</li>
   * <li><em>Throws exceptions instead of returning null values.</em> Because some operations (especially those that may permit the
   * GZIP option) use IO streams, there is a possiblity of an java.io.IOException being thrown. After some discussion and thought,
   * I've changed the behavior of the methods to throw java.io.IOExceptions rather than return null if ever there's an error. I
   * think this is more appropriate, though it will require some changes to your code. Sorry, it should have been done this way to
   * begin with.</li>
   * <li><em>Removed all references to System.out, System.err, and the like.</em> Shame on me. All I can say is sorry they were ever
   * there.</li>
  * <li><em>Throws NullPointerExceptions and IllegalArgumentExceptions</em> as needed such as when passed arrays are null or
  * offsets are invalid.</li>
  * <li>Cleaned up as much javadoc as I could to avoid any javadoc warnings. This was especially annoying before for people who
  * were thorough in their own projects and then had gobs of javadoc warnings on this file.</li>
  * </ul>
  * <li>v2.2.1 - Fixed bug using URL_SAFE and ORDERED encodings. Fixed bug when using very small files (~&lt; 40 bytes).</li>
  * <li>v2.2 - Added some helper methods for encoding/decoding directly from one file to the next. Also added a main() method to
  * support command line encoding/decoding from one file to the next. Also added these Base64 dialects:
  * <ol>
  * <li>The default is RFC3548 format.</li>
  * <li>Calling Base64.setFormat(Base64.BASE64_FORMAT.URLSAFE_FORMAT) generates URL and file name friendly format as described in
  * Section 4 of RFC3548. http://www.faqs.org/rfcs/rfc3548.html</li>
  * <li>Calling Base64.setFormat(Base64.BASE64_FORMAT.ORDERED_FORMAT) generates URL and file name friendly format that preserves
  * lexical ordering as described in http://www.faqs.org/qa/rfcc-1940.html</li>
  * </ol>
  * Special thanks to Jim Kellerman at <a href="http://www.powerset.com/">http://www.powerset.com/</a> for contributing the new
  * Base64 dialects.</li>
  * <li>v2.1 - Cleaned up javadoc comments and unused variables and methods. Added some convenience methods for reading and writing
  * to and from files.</li>
  * <li>v2.0.2 - Now specifies UTF-8 encoding in places where the code fails on systems with other encodings (like EBCDIC).</li>
  * <li>v2.0.1 - Fixed an error when decoding a single byte, that is, when the encoded data was a single byte.</li>
  * <li>v2.0 - I got rid of methods that used booleans to set options. Now everything is more consolidated and cleaner. The code
  * now detects when data that's being decoded is gzip-compressed and will decompress it automatically. Generally things are
  * cleaner. You'll probably have to change some method calls that you were making to support the new options format (<tt>int</tt>s
  * that you "OR" together).</li>
  * <li>v1.5.1 - Fixed bug when decompressing and decoding to a byte[] using <tt>decode( String s, boolean gzipCompressed )</tt>.
  * Added the ability to "suspend" encoding in the Output Stream so you can turn on and off the encoding if you need to embed
  * base64 data in an otherwise "normal" stream (like an XML file).</li>
  * <li>v1.5 - Output stream pases on flush() command but doesn't do anything itself. This helps when using GZIP streams. Added the
  * ability to GZip-compress objects before encoding them.</li>
  * <li>v1.4 - Added helper methods to read/write files.</li>
  * <li>v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.</li>
  * <li>v1.3.5 - Added flag to turn on and off line breaks. Fixed bug in input stream where last buffer being read, if not
  * completely full, was not returned.</li>
  * <li>v1.3.4 - Fixed when "improperly padded stream" error was thrown at the wrong time.</li>
  * <li>v1.3.3 - Fixed I/O streams which were totally messed up.</li>
  * </ul>
  * <p>
  * I am placing this code in the Public Domain. Do with it as you will. This software comes with no guarantees or warranties but
  * with plenty of well-wishing instead! Please visit <a href="http://iharder.net/base64">http://iharder.net/base64</a>
  * periodically to check for updates or to contribute improvements.
  * </p>
  * 
  * @author Robert Harder
  * @author rob@iharder.net
  * @version 2.3.7
  */
 public class Base64 {
 
     /* ********  P U B L I C   F I E L D S  ******** */
 
     /** No options specified. Value is zero. */
     public final static int NO_OPTIONS = 0;
 
     /** Specify encoding in first bit. Value is one. */
     public final static int ENCODE = 1;
 
     /** Specify decoding in first bit. Value is zero. */
     public final static int DECODE = 0;
 
     /** Specify that data should be gzip-compressed in second bit. Value is two. */
     public final static int GZIP = 2;
 
     /** Specify that gzipped data should <em>not</em> be automatically gunzipped. */
     public final static int DONT_GUNZIP = 4;
 
     /** Do break lines when encoding. Value is 8. */
     public final static int DO_BREAK_LINES = 8;
 
     /**
      * Encode using Base64-like encoding that is URL- and Filename-safe as described in Section 4 of RFC3548: <a
      * href="http://www.faqs.org/rfcs/rfc3548.html">http://www.faqs.org/rfcs/rfc3548.html</a>. It is important to note that data
      * encoded this way is <em>not</em> officially valid Base64, or at the very least should not be called Base64 without also
      * specifying that is was encoded using the URL- and Filename-safe dialect.
      */
     public final static int URL_SAFE = 16;
 
     /**
      * Encode using the special "ordered" dialect of Base64 described here: <a
      * href="http://www.faqs.org/qa/rfcc-1940.html">http://www.faqs.org/qa/rfcc-1940.html</a>.
      */
     public final static int ORDERED = 32;
 
     /* ********  P R I V A T E   F I E L D S  ******** */
 
     /** Maximum line length (76) of Base64 output. */
     private final static int MAX_LINE_LENGTH = 76;
 
     /** The equals sign (=) as a byte. */
     private final static byte EQUALS_SIGN = (byte)'=';
 
     /** The new line character (\n) as a byte. */
     private final static byte NEW_LINE = (byte)'\n';
 
     /** Preferred encoding. */
     private final static String PREFERRED_ENCODING = "US-ASCII";
 
     private final static byte WHITE_SPACE_ENC = -5; // Indicates white space in encoding
     private final static byte EQUALS_SIGN_ENC = -1; // Indicates equals sign in encoding
 
     /* ********  S T A N D A R D   B A S E 6 4   A L P H A B E T  ******** */
 
     /** The 64 valid Base64 values. */
     /* Host platform me be something funny like EBCDIC, so we hardcode these values. */
     private final static byte[] _STANDARD_ALPHABET = {(byte)'A', (byte)'B', (byte)'C', (byte)'D', (byte)'E', (byte)'F',
         (byte)'G', (byte)'H', (byte)'I', (byte)'J', (byte)'K', (byte)'L', (byte)'M', (byte)'N', (byte)'O', (byte)'P', (byte)'Q',
         (byte)'R', (byte)'S', (byte)'T', (byte)'U', (byte)'V', (byte)'W', (byte)'X', (byte)'Y', (byte)'Z', (byte)'a', (byte)'b',
         (byte)'c', (byte)'d', (byte)'e', (byte)'f', (byte)'g', (byte)'h', (byte)'i', (byte)'j', (byte)'k', (byte)'l', (byte)'m',
         (byte)'n', (byte)'o', (byte)'p', (byte)'q', (byte)'r', (byte)'s', (byte)'t', (byte)'u', (byte)'v', (byte)'w', (byte)'x',
         (byte)'y', (byte)'z', (byte)'0', (byte)'1', (byte)'2', (byte)'3', (byte)'4', (byte)'5', (byte)'6', (byte)'7', (byte)'8',
         (byte)'9', (byte)'+', (byte)'/'};
 
     /**
      * Translates a Base64 value to either its 6-bit reconstruction value or a negative number indicating some other meaning.
      **/
     private final static byte[] _STANDARD_DECODABET = {-9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8
         -5, -5, // Whitespace: Tab and Linefeed
         -9, -9, // Decimal 11 - 12
         -5, // Whitespace: Carriage Return
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
         -9, -9, -9, -9, -9, // Decimal 27 - 31
         -5, // Whitespace: Space
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
         62, // Plus sign at decimal 43
         -9, -9, -9, // Decimal 44 - 46
         63, // Slash at decimal 47
         52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
         -9, -9, -9, // Decimal 58 - 60
         -1, // Equals sign at decimal 61
         -9, -9, -9, // Decimal 62 - 64
         0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through 'N'
         14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' through 'Z'
         -9, -9, -9, -9, -9, -9, // Decimal 91 - 96
         26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' through 'm'
         39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' through 'z'
         -9, -9, -9, -9, -9 // Decimal 123 - 127
         , -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 128 - 139
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 140 - 152
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 153 - 165
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 166 - 178
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 179 - 191
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 192 - 204
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 205 - 217
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 218 - 230
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 231 - 243
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9 // Decimal 244 - 255
     };
 
     /* ********  U R L   S A F E   B A S E 6 4   A L P H A B E T  ******** */
 
     /**
      * Used in the URL- and Filename-safe dialect described in Section 4 of RFC3548: <a
      * href="http://www.faqs.org/rfcs/rfc3548.html">http://www.faqs.org/rfcs/rfc3548.html</a>. Notice that the last two bytes
      * become "hyphen" and "underscore" instead of "plus" and "slash."
      */
     private final static byte[] _URL_SAFE_ALPHABET = {(byte)'A', (byte)'B', (byte)'C', (byte)'D', (byte)'E', (byte)'F',
         (byte)'G', (byte)'H', (byte)'I', (byte)'J', (byte)'K', (byte)'L', (byte)'M', (byte)'N', (byte)'O', (byte)'P', (byte)'Q',
         (byte)'R', (byte)'S', (byte)'T', (byte)'U', (byte)'V', (byte)'W', (byte)'X', (byte)'Y', (byte)'Z', (byte)'a', (byte)'b',
         (byte)'c', (byte)'d', (byte)'e', (byte)'f', (byte)'g', (byte)'h', (byte)'i', (byte)'j', (byte)'k', (byte)'l', (byte)'m',
         (byte)'n', (byte)'o', (byte)'p', (byte)'q', (byte)'r', (byte)'s', (byte)'t', (byte)'u', (byte)'v', (byte)'w', (byte)'x',
         (byte)'y', (byte)'z', (byte)'0', (byte)'1', (byte)'2', (byte)'3', (byte)'4', (byte)'5', (byte)'6', (byte)'7', (byte)'8',
         (byte)'9', (byte)'-', (byte)'_'};
 
     /**
      * Used in decoding URL- and Filename-safe dialects of Base64.
      */
     private final static byte[] _URL_SAFE_DECODABET = {-9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8
         -5, -5, // Whitespace: Tab and Linefeed
         -9, -9, // Decimal 11 - 12
         -5, // Whitespace: Carriage Return
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
         -9, -9, -9, -9, -9, // Decimal 27 - 31
         -5, // Whitespace: Space
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
         -9, // Plus sign at decimal 43
         -9, // Decimal 44
         62, // Minus sign at decimal 45
         -9, // Decimal 46
         -9, // Slash at decimal 47
         52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
         -9, -9, -9, // Decimal 58 - 60
         -1, // Equals sign at decimal 61
         -9, -9, -9, // Decimal 62 - 64
         0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through 'N'
         14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' through 'Z'
         -9, -9, -9, -9, // Decimal 91 - 94
         63, // Underscore at decimal 95
         -9, // Decimal 96
         26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' through 'm'
         39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' through 'z'
         -9, -9, -9, -9, -9 // Decimal 123 - 127
         , -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 128 - 139
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 140 - 152
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 153 - 165
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 166 - 178
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 179 - 191
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 192 - 204
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 205 - 217
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 218 - 230
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 231 - 243
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9 // Decimal 244 - 255
     };
 
     /* ********  O R D E R E D   B A S E 6 4   A L P H A B E T  ******** */
 
     /**
      * I don't get the point of this technique, but someone requested it, and it is described here: <a
      * href="http://www.faqs.org/qa/rfcc-1940.html">http://www.faqs.org/qa/rfcc-1940.html</a>.
      */
     private final static byte[] _ORDERED_ALPHABET = {(byte)'-', (byte)'0', (byte)'1', (byte)'2', (byte)'3', (byte)'4', (byte)'5',
         (byte)'6', (byte)'7', (byte)'8', (byte)'9', (byte)'A', (byte)'B', (byte)'C', (byte)'D', (byte)'E', (byte)'F', (byte)'G',
         (byte)'H', (byte)'I', (byte)'J', (byte)'K', (byte)'L', (byte)'M', (byte)'N', (byte)'O', (byte)'P', (byte)'Q', (byte)'R',
         (byte)'S', (byte)'T', (byte)'U', (byte)'V', (byte)'W', (byte)'X', (byte)'Y', (byte)'Z', (byte)'_', (byte)'a', (byte)'b',
         (byte)'c', (byte)'d', (byte)'e', (byte)'f', (byte)'g', (byte)'h', (byte)'i', (byte)'j', (byte)'k', (byte)'l', (byte)'m',
         (byte)'n', (byte)'o', (byte)'p', (byte)'q', (byte)'r', (byte)'s', (byte)'t', (byte)'u', (byte)'v', (byte)'w', (byte)'x',
         (byte)'y', (byte)'z'};
 
     /**
      * Used in decoding the "ordered" dialect of Base64.
      */
     private final static byte[] _ORDERED_DECODABET = {-9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8
         -5, -5, // Whitespace: Tab and Linefeed
         -9, -9, // Decimal 11 - 12
         -5, // Whitespace: Carriage Return
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
         -9, -9, -9, -9, -9, // Decimal 27 - 31
         -5, // Whitespace: Space
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
         -9, // Plus sign at decimal 43
         -9, // Decimal 44
         0, // Minus sign at decimal 45
         -9, // Decimal 46
         -9, // Slash at decimal 47
         1, 2, 3, 4, 5, 6, 7, 8, 9, 10, // Numbers zero through nine
         -9, -9, -9, // Decimal 58 - 60
         -1, // Equals sign at decimal 61
         -9, -9, -9, // Decimal 62 - 64
         11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, // Letters 'A' through 'M'
         24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, // Letters 'N' through 'Z'
         -9, -9, -9, -9, // Decimal 91 - 94
         37, // Underscore at decimal 95
         -9, // Decimal 96
         38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, // Letters 'a' through 'm'
         51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, // Letters 'n' through 'z'
         -9, -9, -9, -9, -9 // Decimal 123 - 127
         , -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 128 - 139
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 140 - 152
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 153 - 165
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 166 - 178
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 179 - 191
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 192 - 204
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 205 - 217
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 218 - 230
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 231 - 243
         -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9 // Decimal 244 - 255
     };
 
     /* ********  D E T E R M I N E   W H I C H   A L H A B E T  ******** */
 
     /**
      * Returns one of the _SOMETHING_ALPHABET byte arrays depending on the options specified. It's possible, though silly, to
      * specify ORDERED <b>and</b> URLSAFE in which case one of them will be picked, though there is no guarantee as to which one
      * will be picked.
      * 
      * @param options the options
      * @return the byte array; never null
      */
     private final static byte[] getAlphabet( int options ) {
         if ((options & URL_SAFE) == URL_SAFE) {
             return _URL_SAFE_ALPHABET;
         } else if ((options & ORDERED) == ORDERED) {
             return _ORDERED_ALPHABET;
         } else {
             return _STANDARD_ALPHABET;
         }
     } // end getAlphabet
 
     /**
      * Returns one of the _SOMETHING_DECODABET byte arrays depending on the options specified. It's possible, though silly, to
      * specify ORDERED and URL_SAFE in which case one of them will be picked, though there is no guarantee as to which one will be
      * picked.
      * 
      * @param options the options
      * @return the byte array; never null
      */
     private final static byte[] getDecodabet( int options ) {
         if ((options & URL_SAFE) == URL_SAFE) {
             return _URL_SAFE_DECODABET;
         } else if ((options & ORDERED) == ORDERED) {
             return _ORDERED_DECODABET;
         } else {
             return _STANDARD_DECODABET;
         }
     } // end getAlphabet
 
     /** Defeats instantiation. */
     private Base64() {
     }
 
     /* ********  E N C O D I N G   M E T H O D S  ******** */
 
     /**
      * Encodes up to the first three bytes of array <var>threeBytes</var> and returns a four-byte array in Base64 notation. The
      * actual number of significant bytes in your array is given by <var>numSigBytes</var>. The array <var>threeBytes</var> needs
      * only be as big as <var>numSigBytes</var>. Code can reuse a byte array by passing a four-byte array as <var>b4</var>.
      * 
      * @param b4 A reusable byte array to reduce array instantiation
      * @param threeBytes the array to convert
      * @param numSigBytes the number of significant bytes in your array
      * @param options the options
      * @return four byte array in Base64 notation.
      * @since 1.5.1
      */
     private static byte[] encode3to4( byte[] b4,
                                       byte[] threeBytes,
                                       int numSigBytes,
                                       int options ) {
         encode3to4(threeBytes, 0, numSigBytes, b4, 0, options);
         return b4;
     } // end encode3to4
 
     /**
      * <p>
      * Encodes up to three bytes of the array <var>source</var> and writes the resulting four Base64 bytes to
      * <var>destination</var>. The source and destination arrays can be manipulated anywhere along their length by specifying
      * <var>srcOffset</var> and <var>destOffset</var>. This method does not check to make sure your arrays are large enough to
      * accomodate <var>srcOffset</var> + 3 for the <var>source</var> array or <var>destOffset</var> + 4 for the
      * <var>destination</var> array. The actual number of significant bytes in your array is given by <var>numSigBytes</var>.
      * </p>
      * <p>
      * This is the lowest level of the encoding methods with all possible parameters.
      * </p>
      * 
      * @param source the array to convert
      * @param srcOffset the index where conversion begins
      * @param numSigBytes the number of significant bytes in your array
      * @param destination the array to hold the conversion
      * @param destOffset the index where output will be put
      * @param options the options
      * @return the <var>destination</var> array
      * @since 1.3
      */
     private static byte[] encode3to4( byte[] source,
                                       int srcOffset,
                                       int numSigBytes,
                                       byte[] destination,
                                       int destOffset,
                                       int options ) {
 
         byte[] ALPHABET = getAlphabet(options);
 
         // 1 2 3
         // 01234567890123456789012345678901 Bit position
         // --------000000001111111122222222 Array position from threeBytes
         // --------| || || || | Six bit groups to index ALPHABET
         // >>18 >>12 >> 6 >> 0 Right shift necessary
         // 0x3f 0x3f 0x3f Additional AND
 
         // Create buffer with zero-padding if there are only one or two
         // significant bytes passed in the array.
         // We have to shift left 24 in order to flush out the 1's that appear
         // when Java treats a value as negative that is cast from a byte to an int.
         int inBuff = (numSigBytes > 0 ? ((source[srcOffset] << 24) >>> 8) : 0)
                      | (numSigBytes > 1 ? ((source[srcOffset + 1] << 24) >>> 16) : 0)
                      | (numSigBytes > 2 ? ((source[srcOffset + 2] << 24) >>> 24) : 0);
 
         switch (numSigBytes) {
             case 3:
                 destination[destOffset] = ALPHABET[(inBuff >>> 18)];
                 destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
                 destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
                 destination[destOffset + 3] = ALPHABET[(inBuff) & 0x3f];
                 return destination;
 
             case 2:
                 destination[destOffset] = ALPHABET[(inBuff >>> 18)];
                 destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
                 destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
                 destination[destOffset + 3] = EQUALS_SIGN;
                 return destination;
 
             case 1:
                 destination[destOffset] = ALPHABET[(inBuff >>> 18)];
                 destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
                 destination[destOffset + 2] = EQUALS_SIGN;
                 destination[destOffset + 3] = EQUALS_SIGN;
                 return destination;
 
             default:
                 return destination;
         } // end switch
     } // end encode3to4
 
     /**
      * Encodes content of the supplied InputStream into Base64 notation. Does not GZip-compress data.
      * 
      * @param source The data to convert
      * @return the encoded bytes
      */
     public static String encode( java.io.InputStream source ) {
         return encode(source, NO_OPTIONS);
     }
 
     /**
      * Encodes the content of the supplied InputStream into Base64 notation.
      * <p>
      * Valid options:
      * 
      * <pre>
      *   GZIP: gzip-compresses object before encoding it.
      *   DONT_BREAK_LINES: don't break lines at 76 characters
      *     &lt;i&gt;Note: Technically, this makes your encoding non-compliant.&lt;/i&gt;
      * </pre>
      * <p>
      * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
      * <p>
      * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
      * 
      * @param source The data to convert
      * @param options Specified options- the alphabet type is pulled from this (standard, url-safe, ordered)
      * @return the encoded bytes
      * @see Base64#GZIP
      */
     public static String encode( java.io.InputStream source,
                                  int options ) {
         CheckArg.isNotNull(source, "source");
         java.io.ByteArrayOutputStream baos = new java.io.ByteArrayOutputStream();
         Base64.OutputStream b64os = new Base64.OutputStream(baos, ENCODE | options);
         BufferedInputStream input = new BufferedInputStream(source);
         java.io.OutputStream output = b64os;
 
         boolean error = false;
         try {
             if ((options & GZIP) == GZIP) {
                 output = new java.util.zip.GZIPOutputStream(output);
             }
             int numRead = 0;
             byte[] buffer = new byte[1024];
             while ((numRead = input.read(buffer)) > -1) {
                 output.write(buffer, 0, numRead);
             }
             output.close();
         } catch (IOException e) {
             error = true;
             throw new SystemFailureException(e); // error using reading from byte array!
         } finally {
             try {
                 input.close();
             } catch (IOException e) {
                 if (!error) new SystemFailureException(e); // error closing input stream
             }
         }
 
         // Return value according to relevant encoding.
         try {
             return new String(baos.toByteArray(), PREFERRED_ENCODING);
         } catch (java.io.UnsupportedEncodingException uue) {
             return new String(baos.toByteArray());
         }
     }
 
     /**
      * Performs Base64 encoding on the <code>raw</code> ByteBuffer, writing it to the <code>encoded</code> ByteBuffer. This is an
      * experimental feature. Currently it does not pass along any options (such as {@link #DO_BREAK_LINES} or {@link #GZIP}.
      * 
      * @param raw input buffer
      * @param encoded output buffer
      * @since 2.3
      */
     public static void encode( java.nio.ByteBuffer raw,
                                java.nio.ByteBuffer encoded ) {
         byte[] raw3 = new byte[3];
         byte[] enc4 = new byte[4];
 
         while (raw.hasRemaining()) {
             int rem = Math.min(3, raw.remaining());
             raw.get(raw3, 0, rem);
             Base64.encode3to4(enc4, raw3, rem, Base64.NO_OPTIONS);
             encoded.put(enc4);
         } // end input remaining
     }
 
     /**
      * Performs Base64 encoding on the <code>raw</code> ByteBuffer, writing it to the <code>encoded</code> CharBuffer. This is an
      * experimental feature. Currently it does not pass along any options (such as {@link #DO_BREAK_LINES} or {@link #GZIP}.
      * 
      * @param raw input buffer
      * @param encoded output buffer
      * @since 2.3
      */
     public static void encode( java.nio.ByteBuffer raw,
                                java.nio.CharBuffer encoded ) {
         byte[] raw3 = new byte[3];
         byte[] enc4 = new byte[4];
 
         while (raw.hasRemaining()) {
             int rem = Math.min(3, raw.remaining());
             raw.get(raw3, 0, rem);
             Base64.encode3to4(enc4, raw3, rem, Base64.NO_OPTIONS);
             for (int i = 0; i < 4; i++) {
                 encoded.put((char)(enc4[i] & 0xFF));
             }
         } // end input remaining
     }
 
     /**
      * Serializes an object and returns the Base64-encoded version of that serialized object.
      * <p>
      * As of v 2.3, if the object cannot be serialized or there is another error, the method will throw an java.io.IOException.
      * <b>This is new to v2.3!</b> In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way
      * to handle it.
      * </p>
      * The object is not GZip-compressed before being encoded.
      * 
      * @param serializableObject The object to encode
      * @return The Base64-encoded object
      * @throws java.io.IOException if there is an error
      * @throws NullPointerException if serializedObject is null
      * @since 1.4
      */
     public static String encodeObject( java.io.Serializable serializableObject ) throws java.io.IOException {
         return encodeObject(serializableObject, NO_OPTIONS);
     } // end encodeObject
 
     /**
      * Serializes an object and returns the Base64-encoded version of that serialized object.
      * <p>
      * As of v 2.3, if the object cannot be serialized or there is another error, the method will throw an java.io.IOException.
      * <b>This is new to v2.3!</b> In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way
      * to handle it.
      * </p>
      * The object is not GZip-compressed before being encoded.
      * <p>
      * Example options:
      * 
      * <pre>
      *   GZIP: gzip-compresses object before encoding it.
      *   DO_BREAK_LINES: break lines at 76 characters
      * </pre>
      * <p>
      * Example: <code>encodeObject( myObj, Base64.GZIP )</code> or
      * <p>
      * Example: <code>encodeObject( myObj, Base64.GZIP | Base64.DO_BREAK_LINES )</code>
      * 
      * @param serializableObject The object to encode
      * @param options Specified options
      * @return The Base64-encoded object
      * @see Base64#GZIP
      * @see Base64#DO_BREAK_LINES
      * @throws java.io.IOException if there is an error
      * @since 2.0
      */
     public static String encodeObject( java.io.Serializable serializableObject,
                                        int options ) throws java.io.IOException {
 
         if (serializableObject == null) {
             throw new NullPointerException("Cannot serialize a null object.");
         } // end if: null
 
         // Streams
         java.io.ByteArrayOutputStream baos = null;
         java.io.OutputStream b64os = null;
         java.util.zip.GZIPOutputStream gzos = null;
         java.io.ObjectOutputStream oos = null;
 
         try {
             // ObjectOutputStream -> (GZIP) -> Base64 -> ByteArrayOutputStream
             baos = new java.io.ByteArrayOutputStream();
             b64os = new Base64.OutputStream(baos, ENCODE | options);
             if ((options & GZIP) != 0) {
                 // Gzip
                 gzos = new java.util.zip.GZIPOutputStream(b64os);
                 oos = new java.io.ObjectOutputStream(gzos);
             } else {
                 // Not gzipped
                 oos = new java.io.ObjectOutputStream(b64os);
             }
             oos.writeObject(serializableObject);
         } // end try
         catch (java.io.IOException e) {
             // Catch it and then throw it immediately so that
             // the finally{} block is called for cleanup.
             throw e;
         } // end catch
         finally {
             try {
                 if (oos != null) oos.close();
             } catch (Exception e) {
             }
             try {
                 if (gzos != null) gzos.close();
             } catch (Exception e) {
             }
             try {
                 if (b64os != null) b64os.close();
             } catch (Exception e) {
             }
             try {
                 if (baos != null) baos.close();
             } catch (Exception e) {
             }
         } // end finally
 
         // Return value according to relevant encoding.
         assert baos != null;
         try {
             return new String(baos.toByteArray(), PREFERRED_ENCODING);
         } // end try
         catch (java.io.UnsupportedEncodingException uue) {
             // Fall back to some Java default
             return new String(baos.toByteArray());
         } // end catch
 
     } // end encode
 
     /**
      * Encodes a byte array into Base64 notation. Does not GZip-compress data.
      * 
      * @param source The data to convert
      * @return The data in Base64-encoded form
      * @throws NullPointerException if source array is null
      * @since 1.4
      */
     public static String encodeBytes( byte[] source ) {
         // Since we're not going to have the GZIP encoding turned on,
         // we're not going to have an java.io.IOException thrown, so
         // we should not force the user to have to catch it.
         String encoded = null;
         try {
             encoded = encodeBytes(source, 0, source.length, NO_OPTIONS);
         } catch (java.io.IOException ex) {
             assert false : ex.getMessage();
         } // end catch
         assert encoded != null;
         return encoded;
     } // end encodeBytes
 
     /**
      * Encodes a byte array into Base64 notation.
      * <p>
      * Example options:
      * 
      * <pre>
      *   GZIP: gzip-compresses object before encoding it.
      *   DO_BREAK_LINES: break lines at 76 characters
      *     &lt;i&gt;Note: Technically, this makes your encoding non-compliant.&lt;/i&gt;
      * </pre>
      * <p>
      * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
      * <p>
      * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DO_BREAK_LINES )</code>
      * <p>
      * As of v 2.3, if there is an error with the GZIP stream, the method will throw an java.io.IOException. <b>This is new to
      * v2.3!</b> In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
      * </p>
      * 
      * @param source The data to convert
      * @param options Specified options
      * @return The Base64-encoded data as a String
      * @see Base64#GZIP
      * @see Base64#DO_BREAK_LINES
      * @throws java.io.IOException if there is an error
      * @throws NullPointerException if source array is null
      * @since 2.0
      */
     public static String encodeBytes( byte[] source,
                                       int options ) throws java.io.IOException {
         return encodeBytes(source, 0, source.length, options);
     } // end encodeBytes
 
     /**
      * Encodes a byte array into Base64 notation. Does not GZip-compress data.
      * <p>
      * As of v 2.3, if there is an error, the method will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
      * versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
      * </p>
      * 
      * @param source The data to convert
      * @param off Offset in array where conversion should begin
      * @param len Length of data to convert
      * @return The Base64-encoded data as a String
      * @throws NullPointerException if source array is null
      * @throws IllegalArgumentException if source array, offset, or length are invalid
      * @since 1.4
      */
     public static String encodeBytes( byte[] source,
                                       int off,
                                       int len ) {
         // Since we're not going to have the GZIP encoding turned on,
         // we're not going to have an java.io.IOException thrown, so
         // we should not force the user to have to catch it.
         String encoded = null;
         try {
             encoded = encodeBytes(source, off, len, NO_OPTIONS);
         } catch (java.io.IOException ex) {
             assert false : ex.getMessage();
         } // end catch
         assert encoded != null;
         return encoded;
     } // end encodeBytes
 
     /**
      * Encodes a byte array into Base64 notation.
      * <p>
      * Example options:
      * 
      * <pre>
      *   GZIP: gzip-compresses object before encoding it.
      *   DO_BREAK_LINES: break lines at 76 characters
      *     &lt;i&gt;Note: Technically, this makes your encoding non-compliant.&lt;/i&gt;
      * </pre>
      * <p>
      * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
      * <p>
      * Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DO_BREAK_LINES )</code>
      * <p>
      * As of v 2.3, if there is an error with the GZIP stream, the method will throw an java.io.IOException. <b>This is new to
      * v2.3!</b> In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
      * </p>
      * 
      * @param source The data to convert
      * @param off Offset in array where conversion should begin
      * @param len Length of data to convert
      * @param options Specified options
      * @return The Base64-encoded data as a String
      * @see Base64#GZIP
      * @see Base64#DO_BREAK_LINES
      * @throws java.io.IOException if there is an error
      * @throws NullPointerException if source array is null
      * @throws IllegalArgumentException if source array, offset, or length are invalid
      * @since 2.0
      */
     public static String encodeBytes( byte[] source,
                                       int off,
                                       int len,
                                       int options ) throws java.io.IOException {
         byte[] encoded = encodeBytesToBytes(source, off, len, options);
 
         // Return value according to relevant encoding.
         try {
             return new String(encoded, PREFERRED_ENCODING);
         } // end try
         catch (java.io.UnsupportedEncodingException uue) {
             return new String(encoded);
         } // end catch
 
     } // end encodeBytes
 
     /**
      * Similar to {@link #encodeBytes(byte[])} but returns a byte array instead of instantiating a String. This is more efficient
      * if you're working with I/O streams and have large data sets to encode.
      * 
      * @param source The data to convert
      * @return The Base64-encoded data as a byte[] (of ASCII characters)
      * @throws NullPointerException if source array is null
      * @since 2.3.1
      */
     public static byte[] encodeBytesToBytes( byte[] source ) {
         byte[] encoded = null;
         try {
             encoded = encodeBytesToBytes(source, 0, source.length, Base64.NO_OPTIONS);
         } catch (java.io.IOException ex) {
             assert false : "IOExceptions only come from GZipping, which is turned off: " + ex.getMessage();
         }
         return encoded;
     }
 
     /**
      * Similar to {@link #encodeBytes(byte[], int, int, int)} but returns a byte array instead of instantiating a String. This is
      * more efficient if you're working with I/O streams and have large data sets to encode.
      * 
      * @param source The data to convert
      * @param off Offset in array where conversion should begin
      * @param len Length of data to convert
      * @param options Specified options
      * @return The Base64-encoded data as a String
      * @see Base64#GZIP
      * @see Base64#DO_BREAK_LINES
      * @throws java.io.IOException if there is an error
      * @throws NullPointerException if source array is null
      * @throws IllegalArgumentException if source array, offset, or length are invalid
      * @since 2.3.1
      */
     public static byte[] encodeBytesToBytes( byte[] source,
                                              int off,
                                              int len,
                                              int options ) throws java.io.IOException {
 
         if (source == null) {
             throw new NullPointerException("Cannot serialize a null array.");
         } // end if: null
 
         if (off < 0) {
             throw new IllegalArgumentException("Cannot have negative offset: " + off);
         } // end if: off < 0
 
         if (len < 0) {
             throw new IllegalArgumentException("Cannot have length offset: " + len);
         } // end if: len < 0
 
         if (off + len > source.length) {
             throw new IllegalArgumentException(String.format("Cannot have offset of %d and length of %d with array of length %d",
                                                              off,
                                                              len,
                                                              source.length));
         } // end if: off < 0
 
         // Compress?
         if ((options & GZIP) != 0) {
             java.io.ByteArrayOutputStream baos = null;
             java.util.zip.GZIPOutputStream gzos = null;
             Base64.OutputStream b64os = null;
 
             try {
                 // GZip -> Base64 -> ByteArray
                 baos = new java.io.ByteArrayOutputStream();
                 b64os = new Base64.OutputStream(baos, ENCODE | options);
                 gzos = new java.util.zip.GZIPOutputStream(b64os);
 
                 gzos.write(source, off, len);
                 gzos.close();
             } // end try
             catch (java.io.IOException e) {
                 // Catch it and then throw it immediately so that
                 // the finally{} block is called for cleanup.
                 throw e;
             } // end catch
             finally {
                 try {
                     if (gzos != null) gzos.close();
                 } catch (Exception e) {
                 }
                 try {
                     if (b64os != null) b64os.close();
                 } catch (Exception e) {
                 }
                 try {
                     if (baos != null) baos.close();
                 } catch (Exception e) {
                 }
             } // end finally
 
             assert baos != null;
             return baos.toByteArray();
         } // end if: compress
 
         // Else, don't compress. Better not to use streams at all then.
         boolean breakLines = (options & DO_BREAK_LINES) != 0;
 
         // int len43 = len * 4 / 3;
         // byte[] outBuff = new byte[ ( len43 ) // Main 4:3
         // + ( (len % 3) > 0 ? 4 : 0 ) // Account for padding
         // + (breakLines ? ( len43 / MAX_LINE_LENGTH ) : 0) ]; // New lines
         // Try to determine more precisely how big the array needs to be.
         // If we get it right, we don't have to do an array copy, and
         // we save a bunch of memory.
         int encLen = (len / 3) * 4 + (len % 3 > 0 ? 4 : 0); // Bytes needed for actual encoding
         if (breakLines) {
             encLen += encLen / MAX_LINE_LENGTH; // Plus extra newline characters
         }
         byte[] outBuff = new byte[encLen];
 
         int d = 0;
         int e = 0;
         int len2 = len - 2;
         int lineLength = 0;
         for (; d < len2; d += 3, e += 4) {
             encode3to4(source, d + off, 3, outBuff, e, options);
 
             lineLength += 4;
             if (breakLines && lineLength >= MAX_LINE_LENGTH) {
                 outBuff[e + 4] = NEW_LINE;
                 e++;
                 lineLength = 0;
             } // end if: end of line
         } // en dfor: each piece of array
 
         if (d < len) {
             encode3to4(source, d + off, len - d, outBuff, e, options);
             e += 4;
         } // end if: some padding needed
 
         // Only resize array if we didn't guess it right.
         if (e <= outBuff.length - 1) {
             // If breaking lines and the last byte falls right at
             // the line length (76 bytes per line), there will be
             // one extra byte, and the array will need to be resized.
             // Not too bad of an estimate on array size, I'd say.
             byte[] finalOut = new byte[e];
             System.arraycopy(outBuff, 0, finalOut, 0, e);
             // System.err.println("Having to resize array from " + outBuff.length + " to " + e );
             return finalOut;
         }
         // System.err.println("No need to resize array.");
         return outBuff;
 
     } // end encodeBytesToBytes
 
     /* ********  D E C O D I N G   M E T H O D S  ******** */
 
     /**
      * Decodes four bytes from array <var>source</var> and writes the resulting bytes (up to three of them) to
      * <var>destination</var>. The source and destination arrays can be manipulated anywhere along their length by specifying
      * <var>srcOffset</var> and <var>destOffset</var>. This method does not check to make sure your arrays are large enough to
      * accomodate <var>srcOffset</var> + 4 for the <var>source</var> array or <var>destOffset</var> + 3 for the
      * <var>destination</var> array. This method returns the actual number of bytes that were converted from the Base64 encoding.
      * <p>
      * This is the lowest level of the decoding methods with all possible parameters.
      * </p>
      * 
      * @param source the array to convert
      * @param srcOffset the index where conversion begins
      * @param destination the array to hold the conversion
      * @param destOffset the index where output will be put
      * @param options alphabet type is pulled from this (standard, url-safe, ordered)
      * @return the number of decoded bytes converted
      * @throws NullPointerException if source or destination arrays are null
      * @throws IllegalArgumentException if srcOffset or destOffset are invalid or there is not enough room in the array.
      * @since 1.3
      */
     private static int decode4to3( byte[] source,
                                    int srcOffset,
                                    byte[] destination,
                                    int destOffset,
                                    int options ) {
 
         // Lots of error checking and exception throwing
         if (source == null) {
             throw new NullPointerException("Source array was null.");
         } // end if
         if (destination == null) {
             throw new NullPointerException("Destination array was null.");
         } // end if
         if (srcOffset < 0 || srcOffset + 3 >= source.length) {
             throw new IllegalArgumentException(
                                                String.format("Source array with length %d cannot have offset of %d and still process four bytes.",
                                                              source.length,
                                                              srcOffset));
         } // end if
         if (destOffset < 0 || destOffset + 2 >= destination.length) {
             throw new IllegalArgumentException(
                                                String.format("Destination array with length %d cannot have offset of %d and still store three bytes.",
                                                              destination.length,
                                                              destOffset));
         } // end if
 
         byte[] DECODABET = getDecodabet(options);
 
         // Example: Dk==
         if (source[srcOffset + 2] == EQUALS_SIGN) {
             // Two ways to do the same thing. Don't know which way I like best.
             // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
             // | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 );
             int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12);
 
             destination[destOffset] = (byte)(outBuff >>> 16);
             return 1;
         }
 
         // Example: DkL=
         else if (source[srcOffset + 3] == EQUALS_SIGN) {
             // Two ways to do the same thing. Don't know which way I like best.
             // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
             // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
             // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 );
             int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
                           | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6);
 
             destination[destOffset] = (byte)(outBuff >>> 16);
             destination[destOffset + 1] = (byte)(outBuff >>> 8);
             return 2;
         }
 
         // Example: DkLE
         else {
             // Two ways to do the same thing. Don't know which way I like best.
             // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
             // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
             // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 )
             // | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 );
             int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
                           | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6) | ((DECODABET[source[srcOffset + 3]] & 0xFF));
 
             destination[destOffset] = (byte)(outBuff >> 16);
             destination[destOffset + 1] = (byte)(outBuff >> 8);
             destination[destOffset + 2] = (byte)(outBuff);
 
             return 3;
         }
     } // end decodeToBytes
 
     /**
      * Low-level access to decoding ASCII characters in the form of a byte array. <strong>Ignores GUNZIP option, if it's
      * set.</strong> This is not generally a recommended method, although it is used internally as part of the decoding process.
      * Special case: if len = 0, an empty array is returned. Still, if you need more speed and reduced memory footprint (and
      * aren't gzipping), consider this method.
      * 
      * @param source The Base64 encoded data
      * @return decoded data
      * @throws IOException if there is an error decoding the supplied byte array
      * @since 2.3.1
      */
     public static byte[] decode( byte[] source ) throws IOException {
         byte[] decoded = null;
         // try {
         decoded = decode(source, 0, source.length, Base64.NO_OPTIONS);
         // } catch( java.io.IOException ex ) {
         // assert false : "IOExceptions only come from GZipping, which is turned off: " + ex.getMessage();
         // }
         return decoded;
     }
 
     /**
      * Low-level access to decoding ASCII characters in the form of a byte array. <strong>Ignores GUNZIP option, if it's
      * set.</strong> This is not generally a recommended method, although it is used internally as part of the decoding process.
      * Special case: if len = 0, an empty array is returned. Still, if you need more speed and reduced memory footprint (and
      * aren't gzipping), consider this method.
      * 
      * @param source The Base64 encoded data
      * @param off The offset of where to begin decoding
      * @param len The length of characters to decode
      * @param options Can specify options such as alphabet type to use
      * @return decoded data
      * @throws java.io.IOException If bogus characters exist in source data
      * @since 1.3
      */
     public static byte[] decode( byte[] source,
                                  int off,
                                  int len,
                                  int options ) throws java.io.IOException {
 
         // Lots of error checking and exception throwing
         if (source == null) {
             throw new NullPointerException("Cannot decode null source array.");
         } // end if
         if (off < 0 || off + len > source.length) {
             throw new IllegalArgumentException(
                                                String.format("Source array with length %d cannot have offset of %d and process %d bytes.",
                                                              source.length,
                                                              off,
                                                              len));
         } // end if
 
         if (len == 0) {
             return new byte[0];
         } else if (len < 4) {
             throw new IllegalArgumentException(
                                                "Base64-encoded string must have at least four characters, but length specified was "
                                                + len);
         } // end if
 
         byte[] DECODABET = getDecodabet(options);
 
         int len34 = len * 3 / 4; // Estimate on array size
         byte[] outBuff = new byte[len34]; // Upper limit on size of output
         int outBuffPosn = 0; // Keep track of where we're writing
 
         byte[] b4 = new byte[4]; // Four byte buffer from source, eliminating white space
         int b4Posn = 0; // Keep track of four byte input buffer
         int i = 0; // Source array counter
         byte sbiDecode = 0; // Special value from DECODABET
 
         for (i = off; i < off + len; i++) { // Loop through source
 
             sbiDecode = DECODABET[source[i] & 0xFF];
 
             // White space, Equals sign, or legit Base64 character
             // Note the values such as -5 and -9 in the
             // DECODABETs at the top of the file.
             if (sbiDecode >= WHITE_SPACE_ENC) {
                 if (sbiDecode >= EQUALS_SIGN_ENC) {
                     b4[b4Posn++] = source[i]; // Save non-whitespace
                     if (b4Posn > 3) { // Time to decode?
                         outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn, options);
                         b4Posn = 0;
 
                         // If that was the equals sign, break out of 'for' loop
                         if (source[i] == EQUALS_SIGN) {
                             break;
                         } // end if: equals sign
                     } // end if: quartet built
                 } // end if: equals sign or better
             } // end if: white space, equals sign or better
             else {
                 // There's a bad input character in the Base64 stream.
                 throw new java.io.IOException(String.format("Bad Base64 input character decimal %d in array position %d",
                                                             source[i] & 0xFF,
                                                             i));
             } // end else:
         } // each input character
 
         byte[] out = new byte[outBuffPosn];
         System.arraycopy(outBuff, 0, out, 0, outBuffPosn);
         return out;
     } // end decode
 
     /**
      * Decodes data from Base64 notation, automatically detecting gzip-compressed data and decompressing it.
      * 
      * @param s the string to decode
      * @return the decoded data
      * @throws java.io.IOException If there is a problem
      * @since 1.4
      */
     public static byte[] decode( String s ) throws java.io.IOException {
         return decode(s, NO_OPTIONS);
     }
 
     /**
      * Decodes data from Base64 notation, automatically detecting gzip-compressed data and decompressing it.
      * 
      * @param s the string to decode
      * @param options encode options such as URL_SAFE
      * @return the decoded data
      * @throws java.io.IOException if there is an error
      * @throws NullPointerException if <tt>s</tt> is null
      * @since 1.4
      */
     public static byte[] decode( String s,
                                  int options ) throws java.io.IOException {
 
         if (s == null) {
             throw new NullPointerException("Input string was null.");
         } // end if
 
         byte[] bytes;
         try {
             bytes = s.getBytes(PREFERRED_ENCODING);
         } // end try
         catch (java.io.UnsupportedEncodingException uee) {
             bytes = s.getBytes();
         } // end catch
         // </change>
 
         // Decode
         bytes = decode(bytes, 0, bytes.length, options);
 
         // Check to see if it's gzip-compressed
         // GZIP Magic Two-Byte Number: 0x8b1f (35615)
         boolean dontGunzip = (options & DONT_GUNZIP) != 0;
         if ((bytes != null) && (bytes.length >= 4) && (!dontGunzip)) {
 
             int head = (bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00);
             if (java.util.zip.GZIPInputStream.GZIP_MAGIC == head) {
                 java.io.ByteArrayInputStream bais = null;
                 java.util.zip.GZIPInputStream gzis = null;
                 java.io.ByteArrayOutputStream baos = null;
                 byte[] buffer = new byte[2048];
                 int length = 0;
 
                 try {
                     baos = new java.io.ByteArrayOutputStream();
                     bais = new java.io.ByteArrayInputStream(bytes);
                     gzis = new java.util.zip.GZIPInputStream(bais);
 
                     while ((length = gzis.read(buffer)) >= 0) {
                         baos.write(buffer, 0, length);
                     } // end while: reading input
 
                     // No error? Get new bytes.
                     bytes = baos.toByteArray();
 
                 } // end try
                 catch (java.io.IOException e) {
                     e.printStackTrace();
                     // Just return originally-decoded bytes
                 } // end catch
                 finally {
                     try {
                         if (baos != null) baos.close();
                     } catch (Exception e) {
                     }
                     try {
                         if (gzis != null) gzis.close();
                     } catch (Exception e) {
                     }
                     try {
                         if (bais != null) bais.close();
                     } catch (Exception e) {
                     }
                 } // end finally
 
             } // end if: gzipped
         } // end if: bytes.length >= 2
 
         return bytes;
     } // end decode
 
     /**
      * Attempts to decode Base64 data and deserialize a Java Object within. Returns <tt>null</tt> if there was an error.
      * 
      * @param encodedObject The Base64 data to decode
      * @return The decoded and deserialized object
      * @throws NullPointerException if encodedObject is null
      * @throws java.io.IOException if there is a general error
      * @throws ClassNotFoundException if the decoded object is of a class that cannot be found by the JVM
      * @since 1.5
      */
     public static Object decodeToObject( String encodedObject ) throws java.io.IOException, java.lang.ClassNotFoundException {
         return decodeToObject(encodedObject, NO_OPTIONS, null);
     }
 
     /**
      * Attempts to decode Base64 data and deserialize a Java Object within. Returns <tt>null</tt> if there was an error. If
      * <tt>loader</tt> is not null, it will be the class loader used when deserializing.
      * 
      * @param encodedObject The Base64 data to decode
      * @param options Various parameters related to decoding
      * @param loader Optional class loader to use in deserializing classes.
      * @return The decoded and deserialized object
      * @throws NullPointerException if encodedObject is null
      * @throws java.io.IOException if there is a general error
      * @throws ClassNotFoundException if the decoded object is of a class that cannot be found by the JVM
      * @since 2.3.4
      */
     public static Object decodeToObject( String encodedObject,
                                          int options,
                                          final ClassLoader loader ) throws java.io.IOException, java.lang.ClassNotFoundException {
 
         // Decode and gunzip if necessary
         byte[] objBytes = decode(encodedObject, options);
 
         java.io.ByteArrayInputStream bais = null;
         java.io.ObjectInputStream ois = null;
         Object obj = null;
 
         try {
             bais = new java.io.ByteArrayInputStream(objBytes);
 
             // If no custom class loader is provided, use Java's builtin OIS.
             if (loader == null) {
                 ois = new java.io.ObjectInputStream(bais);
             } // end if: no loader provided
 
             // Else make a customized object input stream that uses
             // the provided class loader.
             else {
                 ois = new java.io.ObjectInputStream(bais) {
                     @Override
                     public Class<?> resolveClass( java.io.ObjectStreamClass streamClass )
                         throws java.io.IOException, ClassNotFoundException {
                         Class<?> c = Class.forName(streamClass.getName(), false, loader);
                         if (c == null) {
                             return super.resolveClass(streamClass);
                         }
                         return c; // Class loader knows of this class.
                     } // end resolveClass
                 }; // end ois
             } // end else: no custom class loader
 
             obj = ois.readObject();
         } // end try
         catch (java.io.IOException e) {
             throw e; // Catch and throw in order to execute finally{}
         } // end catch
         catch (java.lang.ClassNotFoundException e) {
             throw e; // Catch and throw in order to execute finally{}
         } // end catch
         finally {
             try {
                 if (bais != null) bais.close();
             } catch (Exception e) {
             }
             try {
                 if (ois != null) ois.close();
             } catch (Exception e) {
             }
         } // end finally
 
         return obj;
     } // end decodeObject
 
     /**
      * Convenience method for encoding data to a file.
      * <p>
      * As of v 2.3, if there is a error, the method will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
      * versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
      * </p>
      * 
      * @param dataToEncode byte array of data to encode in base64 form
      * @param filename Filename for saving encoded data
      * @throws java.io.IOException if there is an error
      * @throws NullPointerException if dataToEncode is null
      * @since 2.1
      */
     public static void encodeToFile( byte[] dataToEncode,
                                      String filename ) throws java.io.IOException {
 
         if (dataToEncode == null) {
             throw new NullPointerException("Data to encode was null.");
         } // end iff
 
         Base64.OutputStream bos = null;
         try {
             bos = new Base64.OutputStream(new java.io.FileOutputStream(filename), Base64.ENCODE);
             bos.write(dataToEncode);
         } // end try
         catch (java.io.IOException e) {
             throw e; // Catch and throw to execute finally{} block
         } // end catch: java.io.IOException
         finally {
             try {
                 if (bos != null) bos.close();
             } catch (Exception e) {
             }
         } // end finally
 
     } // end encodeToFile
 
     /**
      * Convenience method for decoding data to a file.
      * <p>
      * As of v 2.3, if there is a error, the method will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
      * versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
      * </p>
      * 
      * @param dataToDecode Base64-encoded data as a string
      * @param filename Filename for saving decoded data
      * @throws java.io.IOException if there is an error
      * @since 2.1
      */
     public static void decodeToFile( String dataToDecode,
                                      String filename ) throws java.io.IOException {
 
         Base64.OutputStream bos = null;
         try {
             bos = new Base64.OutputStream(new java.io.FileOutputStream(filename), Base64.DECODE);
             bos.write(dataToDecode.getBytes(PREFERRED_ENCODING));
         } // end try
         catch (java.io.IOException e) {
             throw e; // Catch and throw to execute finally{} block
         } // end catch: java.io.IOException
         finally {
             try {
                 if (bos != null) bos.close();
             } catch (Exception e) {
             }
         } // end finally
 
     } // end decodeToFile
 
     /**
      * Convenience method for reading a base64-encoded file and decoding it.
      * <p>
      * As of v 2.3, if there is a error, the method will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
      * versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
      * </p>
      * 
      * @param filename Filename for reading encoded data
      * @return decoded byte array
      * @throws java.io.IOException if there is an error
      * @since 2.1
      */
     public static byte[] decodeFromFile( String filename ) throws java.io.IOException {
 
         byte[] decodedData = null;
         Base64.InputStream bis = null;
         try {
             // Set up some useful variables
             java.io.File file = new java.io.File(filename);
             byte[] buffer = null;
             int length = 0;
             int numBytes = 0;
 
             // Check for size of file
             if (file.length() > Integer.MAX_VALUE) {
                 throw new java.io.IOException("File is too big for this convenience method (" + file.length() + " bytes).");
             } // end if: file too big for int index
             buffer = new byte[(int)file.length()];
 
             // Open a stream
             bis = new Base64.InputStream(new java.io.BufferedInputStream(new java.io.FileInputStream(file)), Base64.DECODE);
 
             // Read until done
             while ((numBytes = bis.read(buffer, length, 4096)) >= 0) {
                 length += numBytes;
             } // end while
 
             // Save in a variable to return
             decodedData = new byte[length];
             System.arraycopy(buffer, 0, decodedData, 0, length);
 
         } // end try
         catch (java.io.IOException e) {
             throw e; // Catch and release to execute finally{}
         } // end catch: java.io.IOException
         finally {
             try {
                 if (bis != null) bis.close();
             } catch (Exception e) {
             }
         } // end finally
 
         return decodedData;
     } // end decodeFromFile
 
     /**
      * Convenience method for reading a binary file and base64-encoding it.
      * <p>
      * As of v 2.3, if there is a error, the method will throw an java.io.IOException. <b>This is new to v2.3!</b> In earlier
      * versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
      * </p>
      * 
      * @param filename Filename for reading binary data
      * @return base64-encoded string
      * @throws java.io.IOException if there is an error
      * @since 2.1
      */
     public static String encodeFromFile( String filename ) throws java.io.IOException {
 
         String encodedData = null;
         Base64.InputStream bis = null;
         try {
             // Set up some useful variables
             java.io.File file = new java.io.File(filename);
             byte[] buffer = new byte[Math.max((int)(file.length() * 1.4 + 1), 40)]; // Need max() for math on small files
             // (v2.2.1); Need +1 for a few corner cases
             // (v2.3.5)
             int length = 0;
             int numBytes = 0;
 
             // Open a stream
             bis = new Base64.InputStream(new java.io.BufferedInputStream(new java.io.FileInputStream(file)), Base64.ENCODE);
 
             // Read until done
             while ((numBytes = bis.read(buffer, length, 4096)) >= 0) {
                 length += numBytes;
             } // end while
 
             // Save in a variable to return
             encodedData = new String(buffer, 0, length, Base64.PREFERRED_ENCODING);
 
         } // end try
         catch (java.io.IOException e) {
             throw e; // Catch and release to execute finally{}
         } // end catch: java.io.IOException
         finally {
             try {
                 if (bis != null) bis.close();
             } catch (Exception e) {
             }
         } // end finally
 
         return encodedData;
     } // end encodeFromFile
 
     /**
      * Reads <tt>infile</tt> and encodes it to <tt>outfile</tt>.
      * 
      * @param infile Input file
      * @param outfile Output file
      * @throws java.io.IOException if there is an error
      * @since 2.2
      */
     public static void encodeFileToFile( String infile,
                                          String outfile ) throws java.io.IOException {
 
         String encoded = Base64.encodeFromFile(infile);
         java.io.OutputStream out = null;
         try {
             out = new java.io.BufferedOutputStream(new java.io.FileOutputStream(outfile));
             out.write(encoded.getBytes("US-ASCII")); // Strict, 7-bit output.
         } // end try
         catch (java.io.IOException e) {
             throw e; // Catch and release to execute finally{}
         } // end catch
         finally {
             try {
                 if (out != null) out.close();
             } catch (Exception ex) {
             }
         } // end finally
     } // end encodeFileToFile
 
     /**
      * Reads <tt>infile</tt> and decodes it to <tt>outfile</tt>.
      * 
      * @param infile Input file
      * @param outfile Output file
      * @throws java.io.IOException if there is an error
      * @since 2.2
      */
     public static void decodeFileToFile( String infile,
                                          String outfile ) throws java.io.IOException {
 
         byte[] decoded = Base64.decodeFromFile(infile);
         java.io.OutputStream out = null;
         try {
             out = new java.io.BufferedOutputStream(new java.io.FileOutputStream(outfile));
             out.write(decoded);
         } // end try
         catch (java.io.IOException e) {
             throw e; // Catch and release to execute finally{}
         } // end catch
         finally {
             try {
                 if (out != null) out.close();
             } catch (Exception ex) {
             }
         } // end finally
     } // end decodeFileToFile
 
     /* ********  I N N E R   C L A S S   I N P U T S T R E A M  ******** */
 
     /**
      * A {@link Base64.InputStream} will read data from another <tt>java.io.InputStream</tt>, given in the constructor, and
      * encode/decode to/from Base64 notation on the fly.
      * 
      * @see Base64
      * @since 1.3
      */
     public static class InputStream extends java.io.FilterInputStream {
 
         private boolean encode; // Encoding or decoding
         private int position; // Current position in the buffer
         private byte[] buffer; // Small buffer holding converted data
         private int bufferLength; // Length of buffer (3 or 4)
         private int numSigBytes; // Number of meaningful bytes in the buffer
         private int lineLength;
         private boolean breakLines; // Break lines at less than 80 characters
         private int options; // Record options used to create the stream.
         private byte[] decodabet; // Local copies to avoid extra method calls
 
         /**
          * Constructs a {@link Base64.InputStream} in DECODE mode.
          * 
          * @param in the <tt>java.io.InputStream</tt> from which to read data.
          * @since 1.3
          */
         public InputStream( java.io.InputStream in ) {
             this(in, DECODE);
         } // end constructor
 
         /**
          * Constructs a {@link Base64.InputStream} in either ENCODE or DECODE mode.
          * <p>
          * Valid options:
          * 
          * <pre>
          *   ENCODE or DECODE: Encode or Decode as data is read.
          *   DO_BREAK_LINES: break lines at 76 characters
          *     (only meaningful when encoding)&lt;/i&gt;
          * </pre>
          * <p>
          * Example: <code>new Base64.InputStream( in, Base64.DECODE )</code>
          * 
          * @param in the <tt>java.io.InputStream</tt> from which to read data.
          * @param options Specified options
          * @see Base64#ENCODE
          * @see Base64#DECODE
          * @see Base64#DO_BREAK_LINES
          * @since 2.0
          */
         @SuppressWarnings( "synthetic-access" )
         public InputStream( java.io.InputStream in,
                             int options ) {
 
             super(in);
             this.options = options; // Record for later
             this.breakLines = (options & DO_BREAK_LINES) > 0;
             this.encode = (options & ENCODE) > 0;
             this.bufferLength = encode ? 4 : 3;
             this.buffer = new byte[bufferLength];
             this.position = -1;
             this.lineLength = 0;
             this.decodabet = getDecodabet(options);
         } // end constructor
 
         /**
          * Reads enough of the input stream to convert to/from Base64 and returns the next byte.
          * 
          * @return next byte
          * @since 1.3
          */
         @SuppressWarnings( "synthetic-access" )
         @Override
         public int read() throws java.io.IOException {
 
             // Do we need to get data?
             if (position < 0) {
                 if (encode) {
                     byte[] b3 = new byte[3];
                     int numBinaryBytes = 0;
                     for (int i = 0; i < 3; i++) {
                         int b = in.read();
 
                         // If end of stream, b is -1.
                         if (b >= 0) {
                             b3[i] = (byte)b;
                             numBinaryBytes++;
                         } else {
                             break; // out of for loop
                         } // end else: end of stream
 
                     } // end for: each needed input byte
 
                     if (numBinaryBytes > 0) {
                         encode3to4(b3, 0, numBinaryBytes, buffer, 0, options);
                         position = 0;
                         numSigBytes = 4;
                     } // end if: got data
                     else {
                         return -1; // Must be end of stream
                     } // end else
                 } // end if: encoding
 
                 // Else decoding
                 else {
                     byte[] b4 = new byte[4];
                     int i = 0;
                     for (i = 0; i < 4; i++) {
                         // Read four "meaningful" bytes:
                         int b = 0;
                         do {
                             b = in.read();
                         } while (b >= 0 && decodabet[b & 0x7f] <= WHITE_SPACE_ENC);
 
                         if (b < 0) {
                             break; // Reads a -1 if end of stream
                         } // end if: end of stream
 
                         b4[i] = (byte)b;
                     } // end for: each needed input byte
 
                     if (i == 4) {
                         numSigBytes = decode4to3(b4, 0, buffer, 0, options);
                         position = 0;
                     } // end if: got four characters
                     else if (i == 0) {
                         return -1;
                     } // end else if: also padded correctly
                     else {
                         // Must have broken out from above.
                         throw new java.io.IOException("Improperly padded Base64 input.");
                     } // end
 
                 } // end else: decode
             } // end else: get data
 
             // Got data?
             if (position >= 0) {
                 // End of relevant data?
                 if ( /*!encode &&*/position >= numSigBytes) {
                     return -1;
                 } // end if: got data
 
                 if (encode && breakLines && lineLength >= MAX_LINE_LENGTH) {
                     lineLength = 0;
                     return '\n';
                 } // end if
                 lineLength++; // This isn't important when decoding
                 // but throwing an extra "if" seems
                 // just as wasteful.
 
                 int b = buffer[position++];
 
                 if (position >= bufferLength) {
                     position = -1;
                 } // end if: end
 
                 return b & 0xFF; // This is how you "cast" a byte that's
                 // intended to be unsigned.
             } // end if: position >= 0
 
             // Else error
             throw new java.io.IOException("Error in Base64 code reading stream.");
         } // end read
 
         /**
          * Calls {@link #read()} repeatedly until the end of stream is reached or <var>len</var> bytes are read. Returns number of
          * bytes read into array or -1 if end of stream is encountered.
          * 
          * @param dest array to hold values
          * @param off offset for array
          * @param len max number of bytes to read into array
          * @return bytes read into array or -1 if end of stream is encountered.
          * @since 1.3
          */
         @Override
         public int read( byte[] dest,
                          int off,
                          int len ) throws java.io.IOException {
             int i;
             int b;
             for (i = 0; i < len; i++) {
                 b = read();
 
                 if (b >= 0) {
                     dest[off + i] = (byte)b;
                 } else if (i == 0) {
                     return -1;
                 } else {
                     break; // Out of 'for' loop
                 } // Out of 'for' loop
             } // end for: each byte read
             return i;
         } // end read
 
     } // end inner class InputStream
 
     /* ********  I N N E R   C L A S S   O U T P U T S T R E A M  ******** */
 
     /**
      * A {@link Base64.OutputStream} will write data to another <tt>java.io.OutputStream</tt>, given in the constructor, and
      * encode/decode to/from Base64 notation on the fly.
      * 
      * @see Base64
      * @since 1.3
      */
     public static class OutputStream extends java.io.FilterOutputStream {
 
         private boolean encode;
         private int position;
         private byte[] buffer;
         private int bufferLength;
         private int lineLength;
         private boolean breakLines;
         private byte[] b4; // Scratch used in a few places
         private boolean suspendEncoding;
         private int options; // Record for later
         private byte[] decodabet; // Local copies to avoid extra method calls
 
         /**
          * Constructs a {@link Base64.OutputStream} in ENCODE mode.
          * 
          * @param out the <tt>java.io.OutputStream</tt> to which data will be written.
          * @since 1.3
          */
         public OutputStream( java.io.OutputStream out ) {
             this(out, ENCODE);
         } // end constructor
 
         /**
          * Constructs a {@link Base64.OutputStream} in either ENCODE or DECODE mode.
          * <p>
          * Valid options:
          * 
          * <pre>
          *   ENCODE or DECODE: Encode or Decode as data is read.
          *   DO_BREAK_LINES: don't break lines at 76 characters
          *     (only meaningful when encoding)&lt;/i&gt;
          * </pre>
          * <p>
          * Example: <code>new Base64.OutputStream( out, Base64.ENCODE )</code>
          * 
          * @param out the <tt>java.io.OutputStream</tt> to which data will be written.
          * @param options Specified options.
          * @see Base64#ENCODE
          * @see Base64#DECODE
          * @see Base64#DO_BREAK_LINES
          * @since 1.3
          */
         @SuppressWarnings( "synthetic-access" )
         public OutputStream( java.io.OutputStream out,
                              int options ) {
             super(out);
             this.breakLines = (options & DO_BREAK_LINES) != 0;
             this.encode = (options & ENCODE) != 0;
             this.bufferLength = encode ? 3 : 4;
             this.buffer = new byte[bufferLength];
             this.position = 0;
             this.lineLength = 0;
             this.suspendEncoding = false;
             this.b4 = new byte[4];
             this.options = options;
             this.decodabet = getDecodabet(options);
         } // end constructor
 
         /**
          * Writes the byte to the output stream after converting to/from Base64 notation. When encoding, bytes are buffered three
          * at a time before the output stream actually gets a write() call. When decoding, bytes are buffered four at a time.
          * 
          * @param theByte the byte to write
          * @since 1.3
          */
         @SuppressWarnings( "synthetic-access" )
         @Override
         public void write( int theByte ) throws java.io.IOException {
             // Encoding suspended?
             if (suspendEncoding) {
                 this.out.write(theByte);
                 return;
             } // end if: supsended
 
             // Encode?
             if (encode) {
                 buffer[position++] = (byte)theByte;
                 if (position >= bufferLength) { // Enough to encode.
 
                     this.out.write(encode3to4(b4, buffer, bufferLength, options));
 
                     lineLength += 4;
                     if (breakLines && lineLength >= MAX_LINE_LENGTH) {
                         this.out.write(NEW_LINE);
                         lineLength = 0;
                     } // end if: end of line
 
                     position = 0;
                 } // end if: enough to output
             } // end if: encoding
 
             // Else, Decoding
             else {
                 // Meaningful Base64 character?
                 if (decodabet[theByte & 0x7f] > WHITE_SPACE_ENC) {
                     buffer[position++] = (byte)theByte;
                     if (position >= bufferLength) { // Enough to output.
 
                         int len = Base64.decode4to3(buffer, 0, b4, 0, options);
                         out.write(b4, 0, len);
                         position = 0;
                     } // end if: enough to output
                 } // end if: meaningful base64 character
                 else if (decodabet[theByte & 0x7f] != WHITE_SPACE_ENC) {
                     throw new java.io.IOException("Invalid character in Base64 data.");
                 } // end else: not white space either
             } // end else: decoding
         } // end write
 
         /**
          * Calls {@link #write(int)} repeatedly until <var>len</var> bytes are written.
          * 
          * @param theBytes array from which to read bytes
          * @param off offset for array
          * @param len max number of bytes to read into array
          * @since 1.3
          */
         @Override
         public void write( byte[] theBytes,
                            int off,
                            int len ) throws java.io.IOException {
             // Encoding suspended?
             if (suspendEncoding) {
                 this.out.write(theBytes, off, len);
                 return;
             } // end if: supsended
 
             for (int i = 0; i < len; i++) {
                 write(theBytes[off + i]);
             } // end for: each byte written
 
         } // end write
 
         /**
          * Method added by PHIL. [Thanks, PHIL. -Rob] This pads the buffer without closing the stream.
          * 
          * @throws java.io.IOException if there's an error.
          */
         @SuppressWarnings( "synthetic-access" )
         public void flushBase64() throws java.io.IOException {
             if (position > 0) {
                 if (encode) {
                     out.write(encode3to4(b4, buffer, position, options));
                     position = 0;
                 } // end if: encoding
                 else {
                     throw new java.io.IOException("Base64 input not properly padded.");
                 } // end else: decoding
             } // end if: buffer partially full
 
         } // end flush
 
         /**
          * Flushes and closes (I think, in the superclass) the stream.
          * 
          * @since 1.3
          */
         @Override
         public void close() throws java.io.IOException {
             // 1. Ensure that pending characters are written
             flushBase64();
 
             // 2. Actually close the stream
             // Base class both flushes and closes.
             super.close();
 
             buffer = null;
             out = null;
         } // end close
 
         /**
          * Suspends encoding of the stream. May be helpful if you need to embed a piece of base64-encoded data in a stream.
          * 
          * @throws java.io.IOException if there's an error flushing
          * @since 1.5.1
          */
         public void suspendEncoding() throws java.io.IOException {
             flushBase64();
             this.suspendEncoding = true;
         } // end suspendEncoding
 
         /**
          * Resumes encoding of the stream. May be helpful if you need to embed a piece of base64-encoded data in a stream.
          * 
          * @since 1.5.1
          */
         public void resumeEncoding() {
             this.suspendEncoding = false;
         } // end resumeEncoding
 
     } // end inner class OutputStream
 
 } // end class Base64