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转接远程的http接口,服务器响应正确的数据格式必须是JResponse定义的格式。 客户端websocket使用"org.java-websocket:Java-WebSocket:1.5.2",项目地址https://github.com/TooTallNate/Java-WebSocket; 对Java-WebSocket做了适当修改。

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/*
 * Copyright (c) 2010-2020 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 org.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 possibility 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: *
      *
    1. The default is RFC3548 format.
    2. *
    3. 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
    4. *
    5. 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
    6. *
    * 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 static final int NO_OPTIONS = 0; /** * Specify encoding in first bit. Value is one. */ public static final int ENCODE = 1; /** * Specify that data should be gzip-compressed in second bit. Value is two. */ public static final int GZIP = 2; /** * Do break lines when encoding. Value is 8. */ public static final 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 static final int URL_SAFE = 16; /** * Encode using the special "ordered" dialect of Base64 described here: * http://www.faqs.org/qa/rfcc-1940.html. */ public static final int ORDERED = 32; /* ******** P R I V A T E F I E L D S ******** */ /** * Maximum line length (76) of Base64 output. */ private static final int MAX_LINE_LENGTH = 76; /** * The equals sign (=) as a byte. */ private static final byte EQUALS_SIGN = (byte) '='; /** * The new line character (\n) as a byte. */ private static final byte NEW_LINE = (byte) '\n'; /** * Preferred encoding. */ private static final String PREFERRED_ENCODING = "US-ASCII"; private static final 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 static final 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 static final 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 static final 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 static final 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 static final 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 static final 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 static final 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 static final 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 accommodate * 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) { final 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); } 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(); } catch (java.io.IOException e) { // Catch it and then throw it immediately so that // the finally{} block is called for cleanup. throw e; } finally { try { if (gzos != null) { gzos.close(); } } catch (Exception e) { // do nothing } try { if (b64os != null) { b64os.close(); } } catch (Exception e) { // do nothing } try { if (baos != null) { baos.close(); } } catch (Exception e) { // do nothing } } // 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 } // end for: 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 accommodate * 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 final 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 */ @Override public void write(int theByte) throws java.io.IOException { // Encoding suspended? if (suspendEncoding) { this.out.write(theByte); return; } // end if: suspended // 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: suspended 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 } // end inner class OutputStream } // end class Base64





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