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/*
* Copyright (C) 2014 Markus Junginger, greenrobot (http://greenrobot.de)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package de.greenrobot.common;
/**
*
* Encodes and decodes to and from Base64 notation.
*
*
* Homepage: http://iharder.net/base64.
*
*
*
* Example:
*
*
* String encoded = Base64.encode( myByteArray );
* byte[] myByteArray = Base64.decode( encoded );
*
*
* The options 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.
*
*
*
* Note, according to RFC3548, 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.
*
*
*
* The constants defined in Base64 can be OR-ed together to combine options, so you might make a call like this:
*
*
* String encoded = Base64.encodeBytes( mybytes, Base64.GZIP | Base64.DO_BREAK_LINES );
*
* to compress the data before encoding it and then making the output have newline characters.
*
*
* Also...
*
* String encoded = Base64.encodeBytes( crazyString.getBytes() );
*
*
*
*
* Change Log:
*
*
* - 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.
* - 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.
* - v2.3.5 - Fixed bug in {@link #encodeFromFile} where estimated buffer size was wrong for files of size 31, 34, and
* 37 bytes.
* - 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.
* - 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.
* - 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).
* - 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.
* - v2.3 - This is not a drop-in replacement! 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:
*
* - Does not break lines, by default. This is to keep in compliance with RFC3548.
* - Throws exceptions instead of returning null values. 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.
* - Removed all references to System.out, System.err, and the like. Shame on me. All I can say is sorry they
* were ever there.
* - Throws NullPointerExceptions and IllegalArgumentExceptions as needed such as when passed arrays are null
* or offsets are invalid.
* - 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.
*
* - v2.2.1 - Fixed bug using URL_SAFE and ORDERED encodings. Fixed bug when using very small files (~< 40 bytes).
* - 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:
*
* - The default is RFC3548 format.
* - 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
* - 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
*
* Special thanks to Jim Kellerman at http://www.powerset.com/ for contributing
* the new Base64 dialects.
*
* - v2.1 - Cleaned up javadoc comments and unused variables and methods. Added some convenience methods for reading
* and writing to and from files.
* - v2.0.2 - Now specifies UTF-8 encoding in places where the code fails on systems with other encodings (like
* EBCDIC).
* - v2.0.1 - Fixed an error when decoding a single byte, that is, when the encoded data was a single byte.
* - 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 (ints that you "OR" together).
* - v1.5.1 - Fixed bug when decompressing and decoding to a byte[] using
* decode( String s, boolean gzipCompressed ). 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).
* - 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.
* - v1.4 - Added helper methods to read/write files.
* - v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.
* - 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.
* - v1.3.4 - Fixed when "improperly padded stream" error was thrown at the wrong time.
* - v1.3.3 - Fixed I/O streams which were totally messed up.
*
*
*
* 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 http://iharder.net/base64 periodically to check for updates or to contribute
* improvements.
*
*
* @author Robert Harder
* @author [email protected]
* @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 not 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: http://www.faqs.org/rfcs/rfc3548.html. It is important to note
* that data encoded this way is not 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: http://www.faqs.org/qa/rfcc-1940.html.
*/
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: http://www.faqs.org/rfcs/rfc3548.html. 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: http://www.faqs.org/qa/rfcc-1940.html.
*/
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 and 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 threeBytes and returns a four-byte array in Base64
* notation. The actual number of significant bytes in your array is given by numSigBytes. The array
* threeBytes needs only be as big as numSigBytes. Code can reuse a byte array by passing a
* four-byte array as b4.
*
* @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
/**
*
* Encodes up to three bytes of the array source and writes the resulting four Base64 bytes to
* destination. The source and destination arrays can be manipulated anywhere along their length by
* specifying srcOffset and destOffset. This method does not check to make sure your arrays
* are large enough to accomodate srcOffset + 3 for the source array or destOffset
* + 4 for the destination array. The actual number of significant bytes in your array is given by
* numSigBytes.
*
*
* This is the lowest level of the encoding methods with all possible parameters.
*
*
* @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 destination 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 raw ByteBuffer, writing it to the encoded 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 raw ByteBuffer, writing it to the encoded 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.
*
*
* As of v 2.3, if the object cannot be serialized or there is another error, the method will throw an
* java.io.IOException. This is new to v2.3! In earlier versions, it just returned a null value, but in
* retrospect that's a pretty poor way to handle it.
*
*
* 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.
*
*
* As of v 2.3, if the object cannot be serialized or there is another error, the method will throw an
* java.io.IOException. This is new to v2.3! In earlier versions, it just returned a null value, but in
* retrospect that's a pretty poor way to handle it.
*
*
* The object is not GZip-compressed before being encoded.
*
* Example options:
*
*
* GZIP: gzip-compresses object before encoding it.
* DO_BREAK_LINES: break lines at 76 characters
*
*
* Example: encodeObject( myObj, Base64.GZIP ) or
*
* Example: encodeObject( myObj, Base64.GZIP | Base64.DO_BREAK_LINES )
*
* @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 {
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.
*
* Example options:
*
*
* GZIP: gzip-compresses object before encoding it.
* DO_BREAK_LINES: break lines at 76 characters
* Note: Technically, this makes your encoding non-compliant.
*
*
* Example: encodeBytes( myData, Base64.GZIP ) or
*
* Example: encodeBytes( myData, Base64.GZIP | Base64.DO_BREAK_LINES )
*
*
*
* As of v 2.3, if there is an error with the GZIP stream, the method will throw an java.io.IOException. This is
* new to v2.3! In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way
* to handle it.
*
*
*
* @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.
*
*
* As of v 2.3, if there is an error, the method will throw an java.io.IOException. This is new to v2.3! In
* earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
*
*
*
* @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.
*
* Example options:
*
*
* GZIP: gzip-compresses object before encoding it.
* DO_BREAK_LINES: break lines at 76 characters
* Note: Technically, this makes your encoding non-compliant.
*
*
* Example: encodeBytes( myData, Base64.GZIP ) or
*
* Example: encodeBytes( myData, Base64.GZIP | Base64.DO_BREAK_LINES )
*
*
*
* As of v 2.3, if there is an error with the GZIP stream, the method will throw an java.io.IOException. This is
* new to v2.3! In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way
* to handle it.
*
*
*
* @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 {
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 source and writes the resulting bytes (up to three of them) to
* destination. The source and destination arrays can be manipulated anywhere along their length by
* specifying srcOffset and destOffset. This method does not check to make sure your arrays
* are large enough to accomodate srcOffset + 4 for the source array or destOffset
* + 3 for the destination array. This method returns the actual number of bytes that were converted from
* the Base64 encoding.
*
* This is the lowest level of the decoding methods with all possible parameters.
*
*
*
* @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. Ignores GUNZIP option, if it's
* set. 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. Ignores GUNZIP option, if it's
* set. 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 s 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
//
// 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 {
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 null 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 null if there was an error.
* If loader 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);
} 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 (java.lang.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.
*
*
* As of v 2.3, if there is a error, the method will throw an java.io.IOException. This is new to v2.3! In
* earlier versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
*
*
* @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 {
bos.close();
} catch (Exception e) {
}
} // end finally
} // end encodeToFile
/**
* Convenience method for decoding data to a file.
*
*
* As of v 2.3, if there is a error, the method will throw an java.io.IOException. This is new to v2.3! In
* earlier versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
*
*
* @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 {
bos.close();
} catch (Exception e) {
}
} // end finally
} // end decodeToFile
/**
* Convenience method for reading a base64-encoded file and decoding it.
*
*
* As of v 2.3, if there is a error, the method will throw an java.io.IOException. This is new to v2.3! In
* earlier versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
*
*
* @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 {
bis.close();
} catch (Exception e) {
}
} // end finally
return decodedData;
} // end decodeFromFile
/**
* Convenience method for reading a binary file and base64-encoding it.
*
*
* As of v 2.3, if there is a error, the method will throw an java.io.IOException. This is new to v2.3! In
* earlier versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
*
*
* @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 {
bis.close();
} catch (Exception e) {
}
} // end finally
return encodedData;
} // end encodeFromFile
/**
* Reads infile and encodes it to outfile.
*
* @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 infile and decodes it to outfile.
*
* @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 java.io.InputStream, 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 final boolean encode; // Encoding or decoding
private int position; // Current position in the buffer
private final byte[] buffer; // Small buffer holding converted data
private final int bufferLength; // Length of buffer (3 or 4)
private int numSigBytes; // Number of meaningful bytes in the buffer
private int lineLength;
private final boolean breakLines; // Break lines at less than 80 characters
private final int options; // Record options used to create the stream.
private final byte[] decodabet; // Local copies to avoid extra method calls
/**
* Constructs a {@link Base64.InputStream} in DECODE mode.
*
* @param in
* the java.io.InputStream 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.
*
* Valid options:
*
*
* ENCODE or DECODE: Encode or Decode as data is read.
* DO_BREAK_LINES: break lines at 76 characters
* (only meaningful when encoding)
*
*
* Example: new Base64.InputStream( in, Base64.DECODE )
*
*
* @param in
* the java.io.InputStream 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 len 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 java.io.OutputStream, 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 final boolean encode;
private int position;
private byte[] buffer;
private final int bufferLength;
private int lineLength;
private final boolean breakLines;
private final byte[] b4; // Scratch used in a few places
private boolean suspendEncoding;
private final int options; // Record for later
private final byte[] decodabet; // Local copies to avoid extra method calls
/**
* Constructs a {@link Base64.OutputStream} in ENCODE mode.
*
* @param out
* the java.io.OutputStream 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.
*
* Valid options:
*
*
* ENCODE or DECODE: Encode or Decode as data is read.
* DO_BREAK_LINES: don't break lines at 76 characters
* (only meaningful when encoding)
*
*
* Example: new Base64.OutputStream( out, Base64.ENCODE )
*
* @param out
* the java.io.OutputStream 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 len 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