package org.multibit.mbm.utils;
/**
* <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(String, int, 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 (~< 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.
*/
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.
*/
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
* @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
* @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
/**
* 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
* @throws java.io.IOException if there is an error
* @see Base64#GZIP
* @see Base64#DO_BREAK_LINES
* @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 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 {
oos.close();
} catch (Exception e) {
}
try {
gzos.close();
} catch (Exception e) {
}
try {
b64os.close();
} catch (Exception e) {
}
try {
baos.close();
} catch (Exception e) {
}
} // end finally
// Return value according to relevant encoding.
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
* <i>Note: Technically, this makes your encoding non-compliant.</i>
* </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
* @throws java.io.IOException if there is an error
* @throws NullPointerException if source array is null
* @see Base64#GZIP
* @see Base64#DO_BREAK_LINES
* @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
* <i>Note: Technically, this makes your encoding non-compliant.</i>
* </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
* @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
* @see Base64#GZIP
* @see Base64#DO_BREAK_LINES
* @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
* @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
* @see Base64#GZIP
* @see Base64#DO_BREAK_LINES
* @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;
OutputStream b64os = null;
try {
// GZip -> Base64 -> ByteArray
baos = new java.io.ByteArrayOutputStream();
b64os = new 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 {
gzos.close();
} catch (Exception e) {
}
try {
b64os.close();
} catch (Exception e) {
}
try {
baos.close();
} catch (Exception e) {
}
} // end finally
return baos.toByteArray();
} // end if: compress
// Else, don't compress. Better not to use streams at all then.
else {
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;
} else {
// System.err.println("No need to resize array.");
return outBuff;
}
} // end else: don't compress
} // 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
* @since 2.3.1
*/
public static byte[] decode(byte[] source) throws java.io.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", ((int) 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 = ((int) 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 {
baos.close();
} catch (Exception e) {
}
try {
gzis.close();
} catch (Exception e) {
}
try {
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, 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, 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);
} else {
return c; // Class loader knows of this class.
} // end else: not null
} // 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 (ClassNotFoundException e) {
throw e; // Catch and throw in order to execute finally{}
} // end catch
finally {
try {
bais.close();
} catch (Exception e) {
}
try {
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
OutputStream bos = null;
try {
bos = new 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 {
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 {
OutputStream bos = null;
try {
bos = new 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 {
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;
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 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 {
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;
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 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 {
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 {
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 {
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)</i>
* </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
*/
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
*/
@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
else {
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 else
} // end if: position >= 0
// Else error
else {
throw new java.io.IOException("Error in Base64 code reading stream.");
} // end else
} // 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)</i>
* </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
*/
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
*/
@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.
*/
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