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package org.keycloak.common.util;

import java.io.IOException;

/**
 * 

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: *

*
    *
  • v2.3.8 - Fixed automatic gzip decoding, based on the content, * as this may lead to unexpected behaviour. Request either gzipped * or non gzipped decoding as excepted. Automatic encoding is especially * problematic with generated input (see KEYCLOAK-18914 for a detailed case).
  • *
  • 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 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 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: *
      *
    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 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 data should be gunzipped. */ public final static int 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 it * 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 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 ) { 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, without line break your encoding may become non-compliant (see rfc2045 and rfc4648).
     * 
*

* 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 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 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 { return decode( source, 0, source.length, Base64.NO_OPTIONS ); } /** * 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", ((int)source[i])&0xFF, i ) ); } // end else: } // each input character byte[] out = new byte[ outBuffPosn ]; System.arraycopy( outBuff, 0, out, 0, outBuffPosn ); return out; } // end decode /** * Decodes data from Base64 notation, automatically * detecting gzip-compressed data and decompressing it. * * @param s the string to decode * @return the decoded data * @throws java.io.IOException If there is a problem * @since 1.4 */ public static byte[] decode( String s ) throws java.io.IOException { return decode( s, NO_OPTIONS ); } /** * Decodes data from Base64 notation, automatically * detecting gzip-compressed data and decompressing it. * * @param s the string to decode * @param options decode options such as URL_SAFE or GUNZIP * @return the decoded data * @throws java.io.IOException if there is an error (invalid character in source string or gunzip 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 doGunzip = (options & GUNZIP) != 0; if( (bytes != null) && (bytes.length >= 4) && doGunzip ) { int head = ((int)bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00); if( java.util.zip.GZIPInputStream.GZIP_MAGIC != head ) { throw new IOException("Provided data has no GZIP magic header."); } 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 ) { throw new IOException("Failed to gunzip", e); } // 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: bytes.length >= 2 return bytes; } // end decode /* ******** 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 boolean encode; // Encoding or decoding private int position; // Current position in the buffer private byte[] buffer; // Small buffer holding converted data private int bufferLength; // Length of buffer (3 or 4) private int numSigBytes; // Number of meaningful bytes in the buffer private int lineLength; private boolean breakLines; // Break lines at less than 80 characters private int options; // Record options used to create the stream. private byte[] decodabet; // Local copies to avoid extra method calls /** * Constructs a {@link Base64.InputStream} in DECODE mode. * * @param in the 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 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#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





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