All Downloads are FREE. Search and download functionalities are using the official Maven repository.

com.aowagie.text.pdf.codec.Base64 Maven / Gradle / Ivy

Go to download

Version modificada de iText 2.1.7 con el paquete cambiado, adaptaciones menores para firma y dependencias actualizadas.

There is a newer version: 1.5
Show newest version
package com.aowagie.text.pdf.codec;

/**
 * 

Encodes and decodes to and from Base64 notation.

*

Homepage: http://iharder.net/base64.

* *

* Change Log: *

*
    *
  • 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 2.2.1 */ public class Base64 { /* ******** P U B L I C F I E L D S ******** */ /** No options specified. Value is zero. */ private final static int NO_OPTIONS = 0; /** Specify encoding. */ private final static int ENCODE = 1; /** Specify decoding. */ private final static int DECODE = 0; /** Specify that data should be gzip-compressed. */ private final static int GZIP = 2; /** Don't break lines when encoding (violates strict Base64 specification) */ private final static int DONT_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. */ private final static int URL_SAFE = 16; /** * Encode using the special "ordered" dialect of Base64 described here: * http://www.faqs.org/qa/rfcc-1940.html. */ private 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 = "UTF-8"; //$NON-NLS-1$ // I think I end up not using the BAD_ENCODING indicator. //private final static byte BAD_ENCODING = -9; // Indicates error in encoding 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. */ //private final static byte[] ALPHABET; /* 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 // Decimal 123 - 126 /*,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 127 - 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 // Decimal 123 - 126 /*,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 127 - 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 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 // Decimal 123 - 126 /*,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 127 - 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. */ final static byte[] getAlphabet( final 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. */ final static byte[] getDecodabet( final 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( final byte[] b4, final byte[] threeBytes, final int numSigBytes, final int options ) { encode3to4( threeBytes, 0, numSigBytes, b4, 0, options ); return b4; } // end encode3to4 /** *

Encodes up to three bytes of the array source * and writes the resulting four Base64 bytes to destination. * The source and destination arrays can be manipulated * anywhere along their length by specifying * srcOffset and destOffset. * This method does not check to make sure your arrays * are large enough to accomodate srcOffset + 3 for * the source array or destOffset + 4 for * the destination array. * The actual number of significant bytes in your array is * given by numSigBytes.

*

This is the lowest level of the encoding methods with * all possible parameters.

* * @param source the array to convert * @param srcOffset the index where conversion begins * @param numSigBytes the number of significant bytes in your array * @param destination the array to hold the conversion * @param destOffset the index where output will be put * @return the destination array * @since 1.3 */ private static byte[] encode3to4( final byte[] source, final int srcOffset, final int numSigBytes, final byte[] destination, final int destOffset, final 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. final 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 * @since 1.4 */ public static String encodeBytes( final byte[] source ) { return encodeBytes( source, 0, source.length, NO_OPTIONS ); } // end encodeBytes /** * Encodes a byte array into Base64 notation. *

* Valid options:

     *   GZIP: gzip-compresses object before encoding it.
     *   DONT_BREAK_LINES: don't 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.DONT_BREAK_LINES ) * * * @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 * alphabet type is pulled from this (standard, url-safe, ordered) * @see Base64#GZIP * @see Base64#DONT_BREAK_LINES * @since 2.0 */ private static String encodeBytes( final byte[] source, final int off, final int len, final int options ) { // Isolate options final int dontBreakLines = options & DONT_BREAK_LINES; final int gzip = options & GZIP; // Compress? if( gzip == GZIP ) { 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( final java.io.IOException e ) { e.printStackTrace(); return null; } // end catch finally { try{ gzos.close(); } catch( final Exception e ){} try{ b64os.close(); } catch( final Exception e ){} try{ baos.close(); } catch( final Exception e ){} } // end finally // Return value according to relevant encoding. try { return new String( baos.toByteArray(), PREFERRED_ENCODING ); } // end try catch (final java.io.UnsupportedEncodingException uue) { return new String( baos.toByteArray() ); } // end catch } // end if: compress // Else, don't compress. Better not to use streams at all then. else { // Convert option to boolean in way that code likes it. final boolean breakLines = dontBreakLines == 0; final int len43 = len * 4 / 3; final byte[] outBuff = new byte[ len43 // Main 4:3 + ( len % 3 > 0 ? 4 : 0 ) // Account for padding + (breakLines ? len43 / MAX_LINE_LENGTH : 0) ]; // New lines int d = 0; int e = 0; final 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 // Return value according to relevant encoding. try { return new String( outBuff, 0, e, PREFERRED_ENCODING ); } // end try catch (final java.io.UnsupportedEncodingException uue) { return new String( outBuff, 0, e ); } // end catch } // end else: don't compress } // end encodeBytes /* ******** D E C O D I N G M E T H O D S ******** */ /** * Decodes four bytes from array source * and writes the resulting bytes (up to three of them) * to destination. * The source and destination arrays can be manipulated * anywhere along their length by specifying * srcOffset and destOffset. * This method does not check to make sure your arrays * are large enough to accomodate srcOffset + 4 for * the source array or destOffset + 3 for * the destination array. * This method returns the actual number of bytes that * were converted from the Base64 encoding. *

This is the lowest level of the decoding methods with * all possible parameters.

* * * @param source the array to convert * @param srcOffset the index where conversion begins * @param destination the array to hold the conversion * @param destOffset the index where output will be put * @param options alphabet type is pulled from this (standard, url-safe, ordered) * @return the number of decoded bytes converted * @since 1.3 */ private static int decode4to3( final byte[] source, final int srcOffset, final byte[] destination, final int destOffset, final int options ) { 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 ); final 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 ); final 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 { try{ // 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 ); final 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; }catch( final Exception e){ System.out.println(""+source[srcOffset]+ ": " + DECODABET[ source[ srcOffset ] ] ); //$NON-NLS-1$ //$NON-NLS-2$ System.out.println(""+source[srcOffset+1]+ ": " + DECODABET[ source[ srcOffset + 1 ] ] ); //$NON-NLS-1$ //$NON-NLS-2$ System.out.println(""+source[srcOffset+2]+ ": " + DECODABET[ source[ srcOffset + 2 ] ] ); //$NON-NLS-1$ //$NON-NLS-2$ System.out.println(""+source[srcOffset+3]+ ": " + DECODABET[ source[ srcOffset + 3 ] ] ); //$NON-NLS-1$ //$NON-NLS-2$ return -1; } // end catch } } // end decodeToBytes /** * Very low-level access to decoding ASCII characters in * the form of a byte array. Does not support automatically * gunzipping or any other "fancy" features. * * @param source The Base64 encoded data * @param off The offset of where to begin decoding * @param len The length of characters to decode * @return decoded data * @since 1.3 */ private static byte[] decode( final byte[] source, final int off, final int len, final int options ) { final byte[] DECODABET = getDecodabet( options ); final int len34 = len * 3 / 4; final byte[] outBuff = new byte[ len34 ]; // Upper limit on size of output int outBuffPosn = 0; final byte[] b4 = new byte[4]; int b4Posn = 0; int i = 0; byte sbiCrop = 0; byte sbiDecode = 0; for( i = off; i < off+len; i++ ) { sbiCrop = (byte)(source[i] & 0x7f); // Only the low seven bits sbiDecode = DECODABET[ sbiCrop ]; if( sbiDecode >= WHITE_SPACE_ENC ) // White space, Equals sign or better { if( sbiDecode >= EQUALS_SIGN_ENC ) { b4[ b4Posn++ ] = sbiCrop; if( b4Posn > 3 ) { outBuffPosn += decode4to3( b4, 0, outBuff, outBuffPosn, options ); b4Posn = 0; // If that was the equals sign, break out of 'for' loop if( sbiCrop == EQUALS_SIGN ) { break; } } // end if: quartet built } // end if: equals sign or better } // end if: white space, equals sign or better else { System.err.println( "Bad Base64 input character at " + i + ": " + source[i] + "(decimal)" ); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ return null; } // end else: } // each input character final 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 * @since 1.4 */ public static byte[] decode( final String s ) { return decode( s, NO_OPTIONS ); } /** * Decodes data from Base64 notation, automatically * detecting gzip-compressed data and decompressing it. * * @param s the string to decode * @param options encode options such as URL_SAFE * @return the decoded data * @since 1.4 */ private static byte[] decode( final String s, final int options ) { byte[] bytes; try { bytes = s.getBytes( PREFERRED_ENCODING ); } // end try catch( final 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) if( bytes != null && bytes.length >= 4 ) { final int head = bytes[0] & 0xff | bytes[1] << 8 & 0xff00; if( java.util.zip.GZIPInputStream.GZIP_MAGIC == head ) { java.io.ByteArrayInputStream bais = null; java.util.zip.GZIPInputStream gzis = null; java.io.ByteArrayOutputStream baos = null; final 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( final java.io.IOException e ) { // Just return originally-decoded bytes } // end catch finally { try{ baos.close(); } catch( final Exception e ){} try{ gzis.close(); } catch( final Exception e ){} try{ bais.close(); } catch( final Exception e ){} } // end finally } // end if: gzipped } // end if: bytes.length >= 2 return bytes; } // end decode /** * Convenience method for reading a base64-encoded * file and decoding it. * * @param filename Filename for reading encoded data * @return decoded byte array or null if unsuccessful * * @since 2.1 */ private static byte[] decodeFromFile( final String filename ) { byte[] decodedData = null; Base64.InputStream bis = null; try { // Set up some useful variables final java.io.File file = new java.io.File( filename ); byte[] buffer = null; int length = 0; int numBytes = 0; // Check for size of file if( file.length() > Integer.MAX_VALUE ) { System.err.println( "File is too big for this convenience method (" + file.length() + " bytes)." ); //$NON-NLS-1$ //$NON-NLS-2$ return null; } // end if: file too big for int index buffer = new byte[ (int)file.length() ]; // Open a stream bis = new Base64.InputStream( new java.io.BufferedInputStream( new java.io.FileInputStream( file ) ), Base64.DECODE ); // Read until done while( ( numBytes = bis.read( buffer, length, 4096 ) ) >= 0 ) { length += numBytes; } // Save in a variable to return decodedData = new byte[ length ]; System.arraycopy( buffer, 0, decodedData, 0, length ); } // end try catch( final java.io.IOException e ) { System.err.println( "Error decoding from file " + filename ); //$NON-NLS-1$ } // end catch: IOException finally { try{ bis.close(); } catch( final Exception e) {} } // end finally return decodedData; } // end decodeFromFile /** * Convenience method for reading a binary file * and base64-encoding it. * * @param filename Filename for reading binary data * @return base64-encoded string or null if unsuccessful * * @since 2.1 */ private static String encodeFromFile( final String filename ) { String encodedData = null; Base64.InputStream bis = null; try { // Set up some useful variables final java.io.File file = new java.io.File( filename ); final byte[] buffer = new byte[ Math.max((int)(file.length() * 1.4),40) ]; // Need max() for math on small files (v2.2.1) int length = 0; int numBytes = 0; // Open a stream bis = new Base64.InputStream( new java.io.BufferedInputStream( new java.io.FileInputStream( file ) ), Base64.ENCODE ); // Read until done while( ( numBytes = bis.read( buffer, length, 4096 ) ) >= 0 ) { length += numBytes; } // Save in a variable to return encodedData = new String( buffer, 0, length, Base64.PREFERRED_ENCODING ); } // end try catch( final java.io.IOException e ) { System.err.println( "Error encoding from file " + filename ); //$NON-NLS-1$ } // end catch: IOException finally { try{ bis.close(); } catch( final Exception e) {} } // end finally return encodedData; } // end encodeFromFile /** * Reads infile and encodes it to outfile. * * @param infile Input file * @param outfile Output file * @since 2.2 */ private static void encodeFileToFile( final String infile, final String outfile ) { final String encoded = Base64.encodeFromFile( infile ); java.io.OutputStream out = null; try{ out = new java.io.BufferedOutputStream( new java.io.FileOutputStream( outfile ) ); out.write( encoded.getBytes("US-ASCII") ); // Strict, 7-bit output. //$NON-NLS-1$ } // end try catch( final java.io.IOException ex ) { ex.printStackTrace(); } // end catch finally { try { out.close(); } catch( final Exception ex ){} } // end finally } // end encodeFileToFile /** * Reads infile and decodes it to outfile. * * @param infile Input file * @param outfile Output file * @since 2.2 */ private static void decodeFileToFile( final String infile, final String outfile ) { final byte[] decoded = Base64.decodeFromFile( infile ); java.io.OutputStream out = null; try{ out = new java.io.BufferedOutputStream( new java.io.FileOutputStream( outfile ) ); out.write( decoded ); } // end try catch( final java.io.IOException ex ) { ex.printStackTrace(); } // end catch finally { try { out.close(); } catch( final Exception ex ){} } // end finally } // end decodeFileToFile /* ******** I N N E R C L A S S I N P U T S T R E A M ******** */ /** * A {@link Base64.InputStream} will read data from another * java.io.InputStream, given in the constructor, * and encode/decode to/from Base64 notation on the fly. * * @see Base64 * @since 1.3 */ private static class InputStream extends java.io.FilterInputStream { private final boolean encode; // Encoding or decoding private int position; // Current position in the buffer private final byte[] buffer; // Small buffer holding converted data private final int bufferLength; // Length of buffer (3 or 4) private int numSigBytes; // Number of meaningful bytes in the buffer private int lineLength; private final boolean breakLines; // Break lines at less than 80 characters private final int options; // Record options used to create the stream. private final byte[] alphabet; // Local copies to avoid extra method calls private final byte[] decodabet; // Local copies to avoid extra method calls /** * Constructs a {@link Base64.InputStream} in * either ENCODE or DECODE mode. *

* Valid options:

         *   ENCODE or DECODE: Encode or Decode as data is read.
         *   DONT_BREAK_LINES: don't break lines at 76 characters
         *     (only meaningful when encoding)
         *     Note: Technically, this makes your encoding non-compliant.
         * 
*

* 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#DONT_BREAK_LINES * @since 2.0 */ InputStream( final java.io.InputStream in, final int options ) { super( in ); this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES; this.encode = (options & ENCODE) == ENCODE; this.bufferLength = this.encode ? 4 : 3; this.buffer = new byte[ this.bufferLength ]; this.position = -1; this.lineLength = 0; this.options = options; // Record for later, mostly to determine which alphabet to use this.alphabet = getAlphabet(options); 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( this.position < 0 ) { if( this.encode ) { final byte[] b3 = new byte[3]; int numBinaryBytes = 0; for( int i = 0; i < 3; i++ ) { try { final int b = this.in.read(); // If end of stream, b is -1. if( b >= 0 ) { b3[i] = (byte)b; numBinaryBytes++; } // end if: not end of stream } // end try: read catch( final java.io.IOException e ) { // Only a problem if we got no data at all. if( i == 0 ) { throw e; } } // end catch } // end for: each needed input byte if( numBinaryBytes > 0 ) { encode3to4( b3, 0, numBinaryBytes, this.buffer, 0, this.options ); this.position = 0; this.numSigBytes = 4; } // end if: got data else { return -1; } // end else } // end if: encoding // Else decoding else { final byte[] b4 = new byte[4]; int i = 0; for( i = 0; i < 4; i++ ) { // Read four "meaningful" bytes: int b = 0; do{ b = this.in.read(); } while( b >= 0 && this.decodabet[ b & 0x7f ] <= WHITE_SPACE_ENC ); if( b < 0 ) { break; // Reads a -1 if end of stream } b4[i] = (byte)b; } // end for: each needed input byte if( i == 4 ) { this.numSigBytes = decode4to3( b4, 0, this.buffer, 0, this.options ); this.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." ); //$NON-NLS-1$ } // end } // end else: decode } // end else: get data // Got data? if( this.position >= 0 ) { // End of relevant data? if( /*!encode &&*/ this.position >= this.numSigBytes ) { return -1; } if( this.encode && this.breakLines && this.lineLength >= MAX_LINE_LENGTH ) { this.lineLength = 0; return '\n'; } // end if else { this.lineLength++; // This isn't important when decoding // but throwing an extra "if" seems // just as wasteful. final int b = this.buffer[ this.position++ ]; if( this.position >= this.bufferLength ) { this.position = -1; } 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 { // When JDK1.4 is more accepted, use an assertion here. throw new java.io.IOException( "Error in Base64 code reading stream." ); //$NON-NLS-1$ } // 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( final byte[] dest, final int off, final int len ) throws java.io.IOException { int i; int b; for( i = 0; i < len; i++ ) { b = read(); //if( b < 0 && i == 0 ) // return -1; if( b >= 0 ) { dest[off + i] = (byte)b; } else if( i == 0 ) { return -1; } else { break; // 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 */ private static class OutputStream extends java.io.FilterOutputStream { private final boolean encode; private int position; private byte[] buffer; private final int bufferLength; private int lineLength; private final boolean breakLines; private final byte[] b4; // Scratch used in a few places private final boolean suspendEncoding; private final int options; // Record for later private final byte[] alphabet; // Local copies to avoid extra method calls private final byte[] decodabet; // Local copies to avoid extra method calls /** * Constructs a {@link Base64.OutputStream} in * either ENCODE or DECODE mode. *

* Valid options:

         *   ENCODE or DECODE: Encode or Decode as data is read.
         *   DONT_BREAK_LINES: don't break lines at 76 characters
         *     (only meaningful when encoding)
         *     Note: Technically, this makes your encoding non-compliant.
         * 
*

* 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#DONT_BREAK_LINES * @since 1.3 */ OutputStream( final java.io.OutputStream out, final int options ) { super( out ); this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES; this.encode = (options & ENCODE) == ENCODE; this.bufferLength = this.encode ? 3 : 4; this.buffer = new byte[ this.bufferLength ]; this.position = 0; this.lineLength = 0; this.suspendEncoding = false; this.b4 = new byte[4]; this.options = options; this.alphabet = getAlphabet(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(final int theByte) throws java.io.IOException { // Encoding suspended? if( this.suspendEncoding ) { super.out.write( theByte ); return; } // end if: supsended // Encode? if( this.encode ) { this.buffer[ this.position++ ] = (byte)theByte; if( this.position >= this.bufferLength ) // Enough to encode. { this.out.write( encode3to4( this.b4, this.buffer, this.bufferLength, this.options ) ); this.lineLength += 4; if( this.breakLines && this.lineLength >= MAX_LINE_LENGTH ) { this.out.write( NEW_LINE ); this.lineLength = 0; } // end if: end of line this.position = 0; } // end if: enough to output } // end if: encoding // Else, Decoding else { // Meaningful Base64 character? if( this.decodabet[ theByte & 0x7f ] > WHITE_SPACE_ENC ) { this.buffer[ this.position++ ] = (byte)theByte; if( this.position >= this.bufferLength ) // Enough to output. { final int len = Base64.decode4to3( this.buffer, 0, this.b4, 0, this.options ); this.out.write( this.b4, 0, len ); //out.write( Base64.decode4to3( buffer ) ); this.position = 0; } // end if: enough to output } // end if: meaningful base64 character else if( this.decodabet[ theByte & 0x7f ] != WHITE_SPACE_ENC ) { throw new java.io.IOException( "Invalid character in Base64 data." ); //$NON-NLS-1$ } // 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( final byte[] theBytes, final int off, final int len ) throws java.io.IOException { // Encoding suspended? if( this.suspendEncoding ) { super.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. */ private void flushBase64() throws java.io.IOException { if( this.position > 0 ) { if( this.encode ) { this.out.write( encode3to4( this.b4, this.buffer, this.position, this.options ) ); this.position = 0; } // end if: encoding else { throw new java.io.IOException( "Base64 input not properly padded." ); //$NON-NLS-1$ } // 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(); this.buffer = null; this.out = null; } // end close } // end inner class OutputStream } // end class Base64





© 2015 - 2024 Weber Informatics LLC | Privacy Policy