com.aowagie.text.pdf.codec.Base64 Maven / Gradle / Ivy
package com.aowagie.text.pdf.codec;
import java.nio.charset.StandardCharsets;
/**
* 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:
*
* - The default is RFC3548 format.
* - Calling Base64.setFormat(Base64.BASE64_FORMAT.URLSAFE_FORMAT) generates
* URL and file name friendly format as described in Section 4 of RFC3548.
* http://www.faqs.org/rfcs/rfc3548.html
* - Calling Base64.setFormat(Base64.BASE64_FORMAT.ORDERED_FORMAT) generates
* URL and file name friendly format that preserves lexical ordering as described
* in http://www.faqs.org/qa/rfcc-1940.html
*
* Special thanks to Jim Kellerman at http://www.powerset.com/
* for contributing the new Base64 dialects.
*
*
* - v2.1 - Cleaned up javadoc comments and unused variables and methods. Added
* some convenience methods for reading and writing to and from files.
* - v2.0.2 - Now specifies UTF-8 encoding in places where the code fails on systems
* with other encodings (like EBCDIC).
* - v2.0.1 - Fixed an error when decoding a single byte, that is, when the
* encoded data was a single byte.
* - v2.0 - I got rid of methods that used booleans to set options.
* Now everything is more consolidated and cleaner. The code now detects
* when data that's being decoded is gzip-compressed and will decompress it
* automatically. Generally things are cleaner. You'll probably have to
* change some method calls that you were making to support the new
* options format (ints that you "OR" together).
* - v1.5.1 - Fixed bug when decompressing and decoding to a
* byte[] using decode( String s, boolean gzipCompressed ).
* Added the ability to "suspend" encoding in the Output Stream so
* you can turn on and off the encoding if you need to embed base64
* data in an otherwise "normal" stream (like an XML file).
* - v1.5 - Output stream pases on flush() command but doesn't do anything itself.
* This helps when using GZIP streams.
* Added the ability to GZip-compress objects before encoding them.
* - v1.4 - Added helper methods to read/write files.
* - v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.
* - v1.3.5 - Added flag to turn on and off line breaks. Fixed bug in input stream
* where last buffer being read, if not completely full, was not returned.
* - v1.3.4 - Fixed when "improperly padded stream" error was thrown at the wrong time.
* - v1.3.3 - Fixed I/O streams which were totally messed up.
*
*
*
* I am placing this code in the Public Domain. Do with it as you will.
* This software comes with no guarantees or warranties but with
* plenty of well-wishing instead!
* Please visit http://iharder.net/base64
* periodically to check for updates or to contribute improvements.
*
*
* @author Robert Harder
* @author [email protected]
* @version 2.2.1
*/
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 = StandardCharsets.UTF_8.name();
// 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.
*/
private 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.
*/
private 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(){}
/**
* Encodes or decodes two files from the command line;
* feel free to delete this method (in fact you probably should)
* if you're embedding this code into a larger program.
* @param args args to send
*/
public final static void main( final String[] args ) {
if( args.length < 3 ){
usage("Not enough arguments.");
} // end if: args.length < 3
else {
final String flag = args[0];
final String infile = args[1];
final String outfile = args[2];
if( flag.equals( "-e" ) ){
Base64.encodeFileToFile( infile, outfile );
} // end if: encode
else if( flag.equals( "-d" ) ) {
Base64.decodeFileToFile( infile, outfile );
} // end else if: decode
else {
usage( "Unknown flag: " + flag );
} // end else
} // end else
} // end main
/**
* Prints command line usage.
*
* @param msg A message to include with usage info.
*/
private final static void usage( final String msg ) {
System.err.println( msg );
System.err.println( "Usage: java Base64 -e|-d inputfile outputfile" );
} // end usage
/* ******** 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
* @return a encode String
*/
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 ] ] );
System.out.println(""+source[srcOffset+1]+ ": " + DECODABET[ source[ srcOffset + 1 ] ] );
System.out.println(""+source[srcOffset+2]+ ": " + DECODABET[ source[ srcOffset + 2 ] ] );
System.out.println(""+source[srcOffset+3]+ ": " + DECODABET[ source[ srcOffset + 3 ] ] );
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)" );
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)." );
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 );
} // 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 );
} // 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.
} // 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
*/
private 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." );
} // 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." );
} // 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
*/
private 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." );
} // 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." );
} // 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