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Alipay openapi SDK for Java
Copyright © 2018 杭州蚂蚁金服
All rights reserved.
版权所有 （C）杭州蚂蚁金服
http://open.alipay.com
/*
* Copyright (c) 2010-2018 Nathan Rajlich
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
package com.alipay.api.java_websocket.util;
/**
* 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.
* - v2.3.4 - 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 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 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 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 that data should be gzip-compressed in second bit. Value is two.
*/
public final static int GZIP = 2;
/**
* 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
/* ******** 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
/**
* 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 IllegalArgumentException 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 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 IllegalArgumentException if source array is null, 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[], 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 IllegalArgumentException if source array is null, 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 IllegalArgumentException("Cannot serialize a null array.");
} // end if: null
if (off < 0) {
throw new IllegalArgumentException("Cannot have negative offset: " + off);
} // end if: off < 0
if (len < 0) {
throw new IllegalArgumentException("Cannot have length offset: " + len);
} // end if: len < 0
if (off + len > source.length) {
throw new IllegalArgumentException(
String.format("Cannot have offset of %d and length of %d with array of length %d", off, len, source.length));
} // end if: off < 0
// Compress?
if ((options & GZIP) != 0) {
java.io.ByteArrayOutputStream baos = null;
java.util.zip.GZIPOutputStream gzos = null;
Base64.OutputStream b64os = null;
try {
// GZip -> Base64 -> ByteArray
baos = new java.io.ByteArrayOutputStream();
b64os = new Base64.OutputStream(baos, ENCODE | options);
gzos = new java.util.zip.GZIPOutputStream(b64os);
gzos.write(source, off, len);
gzos.close();
} // end try
catch (java.io.IOException e) {
// Catch it and then throw it immediately so that
// the finally{} block is called for cleanup.
throw e;
} // end catch
finally {
try {
if (gzos != null) { gzos.close(); }
} catch (Exception e) {}
try {
if (b64os != null) { b64os.close(); }
} catch (Exception e) {}
try {
if (baos != null) { baos.close(); }
} catch (Exception e) {}
} // end finally
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 IllegalArgumentException if source or destination arrays are null, 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 IllegalArgumentException("Source array was null.");
} // end if
if (destination == null) {
throw new IllegalArgumentException("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
/**
* 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 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 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#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
*/
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
*/
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
*/
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
} // end inner class OutputStream
} // end class Base64