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package com.googlecode.pngtastic.core.processing;
import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectStreamClass;
import java.io.Serializable;
import java.io.UnsupportedEncodingException;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
/**
* Encodes and decodes to and from Base64 notation.
* Homepage: http://iharder.net/base64.
*
* Example:
* String encoded = Base64.encode(myByteArray);
*
* byte[] myByteArray = Base64.decode(encoded);
*
* The options parameter, which appears in a few places, is used to pass
* several pieces of information to the encoder. In the "higher level" methods such as
* encodeBytes(bytes, options) the options parameter can be used to indicate such
* things as first gzipping the bytes before encoding them, not inserting linefeeds,
* and encoding using the URL-safe and Ordered dialects.
*
* Note, according to RFC3548,
* Section 2.1, implementations should not add line feeds unless explicitly told
* to do so. I've got Base64 set to this behavior now, although earlier versions
* broke lines by default.
*
* The constants defined in Base64 can be OR-ed together to combine options, so you
* might make a call like this:
*
* String encoded = Base64.encodeBytes(mybytes, Base64.GZIP | Base64.DO_BREAK_LINES);
* to compress the data before encoding it and then making the output have newline characters.
* Also...
* String encoded = Base64.encodeBytes( crazyString.getBytes() );
*
* Change Log:
*
*
* - v2.3.7 - Fixed subtle bug when base 64 input stream contained the
* value 01111111, which is an invalid base 64 character but should not
* throw an ArrayIndexOutOfBoundsException either. Led to discovery of
* mishandling (or potential for better handling) of other bad input
* characters. You should now get an IOException if you try decoding
* something that has bad characters in it.
* - v2.3.6 - Fixed bug when breaking lines and the final byte of the encoded
* string ended in the last column; the buffer was not properly shrunk and
* contained an extra (null) byte that made it into the string.
* - v2.3.5 - 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 possiblity of an java.io.IOException being thrown. After some discussion and
* thought, I've changed the behavior of the methods to throw java.io.IOExceptions
* rather than return null if ever there's an error. I think this is more
* appropriate, though it will require some changes to your code. Sorry,
* it should have been done this way to begin with.
* - Removed all references to System.out, System.err, and the like.
* Shame on me. All I can say is sorry they were ever there.
* - Throws 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:
*
* - The default is RFC3548 format.
* - Calling Base64.setFormat(Base64.BASE64_FORMAT.URLSAFE_FORMAT) generates
* URL and file name friendly format as described in Section 4 of RFC3548.
* http://www.faqs.org/rfcs/rfc3548.html
* - Calling Base64.setFormat(Base64.BASE64_FORMAT.ORDERED_FORMAT) generates
* URL and file name friendly format that preserves lexical ordering as described
* in http://www.faqs.org/qa/rfcc-1940.html
*
* Special thanks to Jim Kellerman at http://www.powerset.com/
* for contributing the new Base64 dialects.
*
*
* - v2.1 - Cleaned up javadoc comments and unused variables and methods. Added
* some convenience methods for reading and writing to and from files.
* - v2.0.2 - Now specifies UTF-8 encoding in places where the code fails on systems
* with other encodings (like EBCDIC).
* - v2.0.1 - Fixed an error when decoding a single byte, that is, when the
* encoded data was a single byte.
* - v2.0 - I got rid of methods that used booleans to set options.
* Now everything is more consolidated and cleaner. The code now detects
* when data that's being decoded is gzip-compressed and will decompress it
* automatically. Generally things are cleaner. You'll probably have to
* change some method calls that you were making to support the new
* options format (ints that you "OR" together).
* - v1.5.1 - Fixed bug when decompressing and decoding to a
* byte[] using decode( String s, boolean gzipCompressed ).
* Added the ability to "suspend" encoding in the Output Stream so
* you can turn on and off the encoding if you need to embed base64
* data in an otherwise "normal" stream (like an XML file).
* - v1.5 - Output stream pases on flush() command but doesn't do anything itself.
* This helps when using GZIP streams.
* Added the ability to GZip-compress objects before encoding them.
* - v1.4 - Added helper methods to read/write files.
* - v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.
* - v1.3.5 - Added flag to turn on and off line breaks. Fixed bug in input stream
* where last buffer being read, if not completely full, was not returned.
* - v1.3.4 - Fixed when "improperly padded stream" error was thrown at the wrong time.
* - v1.3.3 - Fixed I/O streams which were totally messed up.
*
*
*
* I am placing this code in the Public Domain. Do with it as you will.
* This software comes with no guarantees or warranties but with
* plenty of well-wishing instead!
* Please visit http://iharder.net/base64
* periodically to check for updates or to contribute improvements.
*
*
* @author Robert Harder
* @author [email protected]
* @version 2.3.7
*/
class Base64 {
/** 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 gzipped data should not be automatically gunzipped. */
public final static int DONT_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 is
* was encoded using the URL- and Filename-safe dialect.
*/
public final static int URL_SAFE = 16;
/**
* Encode using the special "ordered" dialect of Base64 described here:
* http://www.faqs.org/qa/rfcc-1940.html.
*/
public final static int ORDERED = 32;
/** 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
/** 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
};
/**
* 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
};
/**
* 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
};
/**
* 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;
}
}
/** Defeats instantiation. */
private Base64() { }
/**
* 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;
}
/**
* Encodes up to three bytes of the array source
* and writes the resulting four Base64 bytes to destination.
* The source and destination arrays can be manipulated anywhere along their length by
* specifying srcOffset and destOffset.
* This method does not check to make sure your arrays are large enough to accomodate
* srcOffset + 3 for the source array or destOffset + 4 for
* the destination array.
* The actual number of significant bytes in your array is given by numSigBytes.
* This is the lowest level of the encoding methods with all possible parameters.
*
* @param source the array to convert
* @param srcOffset the index where conversion begins
* @param numSigBytes the number of significant bytes in your array
* @param destination the array to hold the conversion
* @param destOffset the index where output will be put
* @return the destination array
* @since 1.3
*/
private static byte[] encode3to4(byte[] source, int srcOffset, int numSigBytes,
byte[] destination, int destOffset, int options) {
byte[] ALPHABET = getAlphabet(options);
// 1 2 3
// 01234567890123456789012345678901 Bit position
// --------000000001111111122222222 Array position from threeBytes
// --------| || || || | Six bit groups to index ALPHABET
// >>18 >>12 >> 6 >> 0 Right shift necessary
// 0x3f 0x3f 0x3f Additional AND
// Create buffer with zero-padding if there are only one or two
// significant bytes passed in the array.
// We have to shift left 24 in order to flush out the 1's that appear
// when Java treats a value as negative that is cast from a byte to an int.
int inBuff = (numSigBytes > 0 ? ((source[srcOffset ] << 24) >>> 8) : 0)
| (numSigBytes > 1 ? ((source[srcOffset + 1 ] << 24) >>> 16) : 0)
| (numSigBytes > 2 ? ((source[srcOffset + 2 ] << 24) >>> 24) : 0);
switch (numSigBytes) {
case 3:
destination[destOffset ] = ALPHABET[(inBuff >>> 18) ];
destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
destination[destOffset + 3] = ALPHABET[(inBuff ) & 0x3f];
return destination;
case 2:
destination[destOffset ] = ALPHABET[(inBuff >>> 18) ];
destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
destination[destOffset + 3] = EQUALS_SIGN;
return destination;
case 1:
destination[destOffset ] = ALPHABET[(inBuff >>> 18) ];
destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
destination[destOffset + 2] = EQUALS_SIGN;
destination[destOffset + 3] = EQUALS_SIGN;
return destination;
default:
return destination;
}
}
/**
* 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(ByteBuffer raw, 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);
}
}
/**
* 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(ByteBuffer raw, 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));
}
}
}
/**
* 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(Serializable serializableObject) throws IOException {
return encodeObject(serializableObject, NO_OPTIONS);
}
/**
* 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(Serializable serializableObject, int options) throws IOException {
if (serializableObject == null){
throw new NullPointerException("Cannot serialize a null object.");
}
// Streams
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);
} catch (IOException e) {
// Catch it and then throw it immediately so that the finally{} block is called for cleanup.
throw e;
} finally {
try {
if (oos != null) {
oos.close();
}
} catch (Exception e) {
}
try {
if (gzos != null) {
gzos.close();
}
} catch (Exception e) {
}
try {
if (b64os != null) {
b64os.close();
}
} catch (Exception e) {
}
try {
if (baos != null) {
baos.close();
}
} catch (Exception e) {
}
}
// Return value according to relevant encoding.
try {
return (baos == null) ? null : new String(baos.toByteArray(), PREFERRED_ENCODING);
} catch (UnsupportedEncodingException e) {
// Fall back to some Java default
return new String(baos.toByteArray());
}
}
/**
* 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
// 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();
}
assert encoded != null;
return encoded;
}
/**
* 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 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 IOException {
return encodeBytes(source, 0, source.length, options);
}
/**
* 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
// 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 (IOException ex) {
assert false : ex.getMessage();
}
assert encoded != null;
return encoded;
}
/**
* 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
* 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 IOException {
byte[] encoded = encodeBytesToBytes(source, off, len, options);
// Return value according to relevant encoding.
try {
return new String(encoded, PREFERRED_ENCODING);
}
catch (UnsupportedEncodingException uue) {
return new String(encoded);
}
}
/**
* 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(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 IOException {
if (source == null) {
throw new NullPointerException("Cannot serialize a null array.");
}
if (off < 0) {
throw new IllegalArgumentException("Cannot have negative offset: " + off);
}
if (len < 0) {
throw new IllegalArgumentException("Cannot have length offset: " + len);
}
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));
}
// Compress?
if ((options & GZIP) != 0) {
ByteArrayOutputStream baos = null;
java.util.zip.GZIPOutputStream gzos = null;
Base64.OutputStream b64os = null;
try {
// GZip -> Base64 -> ByteArray
baos = new ByteArrayOutputStream();
b64os = new Base64.OutputStream(baos, ENCODE | options);
gzos = new java.util.zip.GZIPOutputStream(b64os);
gzos.write(source, off, len);
gzos.close();
}
catch (IOException e) {
// Catch it and then throw it immediately so that the finally{} block is called for cleanup.
throw e;
} finally {
try {
if (gzos != null) {
gzos.close();
}
} catch (Exception e) {
}
try {
if (b64os != null) {
b64os.close();
}
} catch (Exception e) {
}
try {
if (baos != null) {
baos.close();
}
} catch (Exception e) {
}
}
return (baos == null) ? null : baos.toByteArray();
} else {
// Else, don't compress. Better not to use streams at all then.
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;
}
}
if (d < len) {
encode3to4(source, d+off, len - d, outBuff, e, options);
e += 4;
}
// 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);
return finalOut;
} else {
return outBuff;
}
}
}
/**
* Decodes four bytes from array source and writes the resulting bytes
* (up to three of them) to destination. The source and destination arrays can be
* manipulated anywhere along their length by specifying srcOffset and
* destOffset. This method does not check to make sure your arrays are large enough
* to accomodate srcOffset + 4 for the source array or
* destOffset + 3 for the destination array. This method returns the
* actual number of bytes that were converted from the Base64 encoding.
*
* This is the lowest level of the decoding methods with all possible parameters.
*
* @param source the array to convert
* @param srcOffset the index where conversion begins
* @param destination the array to hold the conversion
* @param destOffset the index where output will be put
* @param options alphabet type is pulled from this (standard, url-safe, ordered)
* @return the number of decoded bytes converted
* @throws 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.");
}
if (destination == null) {
throw new NullPointerException("Destination array was null.");
}
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));
}
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));
}
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;
} else if (source[srcOffset + 3] == EQUALS_SIGN) {
// Example: DkL=
// 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;
} else {
// Example: DkLE
// 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;
}
}
/**
* 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 IOException {
byte[] decoded = null;
// try {
decoded = decode(source, 0, source.length, Base64.NO_OPTIONS);
// } catch (IOException ex) {
// assert false : "IOExceptions only come from GZipping, which is turned off: " + ex.getMessage();
// }
return decoded;
}
/**
* 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 IOException If bogus characters exist in source data
* @since 1.3
*/
public static byte[] decode(byte[] source, int off, int len, int options) throws IOException {
// Lots of error checking and exception throwing
if (source == null) {
throw new NullPointerException("Cannot decode null source array.");
}
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));
}
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);
}
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 or better
} else {
// There's a bad input character in the Base64 stream.
throw new IOException(String.format(
"Bad Base64 input character decimal %d in array position %d", (source[i]) &0xFF, i));
}
}
byte[] out = new byte[outBuffPosn];
System.arraycopy(outBuff, 0, out, 0, outBuffPosn);
return out;
}
/**
* Decodes data from Base64 notation, automatically detecting gzip-compressed data and decompressing it.
*
* @param s the string to decode
* @return the decoded data
* @throws IOException If there is a problem
* @since 1.4
*/
public static byte[] decode(String s) throws 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 encode options such as URL_SAFE
* @return the decoded data
* @throws IOException if there is an error
* @throws NullPointerException if s is null
* @since 1.4
*/
public static byte[] decode(String s, int options) throws IOException {
if (s == null) {
throw new NullPointerException("Input string was null.");
}
byte[] bytes;
try {
bytes = s.getBytes(PREFERRED_ENCODING);
}
catch (UnsupportedEncodingException e) {
bytes = s.getBytes();
}
// Decode
bytes = decode(bytes, 0, bytes.length, options);
// Check to see if it's gzip-compressed
// GZIP Magic Two-Byte Number: 0x8b1f (35615)
boolean dontGunzip = (options & DONT_GUNZIP) != 0;
if ((bytes != null) && (bytes.length >= 4) && (!dontGunzip)) {
int head = (bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00);
if (java.util.zip.GZIPInputStream.GZIP_MAGIC == head) {
ByteArrayInputStream bais = null;
java.util.zip.GZIPInputStream gzis = null;
ByteArrayOutputStream baos = null;
byte[] buffer = new byte[2048];
int length = 0;
try {
baos = new ByteArrayOutputStream();
bais = new ByteArrayInputStream(bytes);
gzis = new java.util.zip.GZIPInputStream(bais);
while ((length = gzis.read(buffer)) >= 0) {
baos.write(buffer,0,length);
}
// No error? Get new bytes.
bytes = baos.toByteArray();
}
catch (IOException e) {
e.printStackTrace(); // Just return originally-decoded bytes
}
finally {
try {
if (baos != null) {
baos.close();
}
} catch (Exception e) {
}
try {
if (gzis != null) {
gzis.close();
}
} catch (Exception e) {
}
try {
if (bais != null) {
bais.close();
}
} catch (Exception e) {
}
}
}
}
return bytes;
}
/**
* Attempts to decode Base64 data and deserialize a Java
* Object within. Returns null if there was an error.
*
* @param encodedObject The Base64 data to decode
* @return The decoded and deserialized object
* @throws NullPointerException if encodedObject is null
* @throws IOException if there is a general error
* @throws ClassNotFoundException if the decoded object is of a class that cannot be found by the JVM
* @since 1.5
*/
public static Object decodeToObject(String encodedObject) throws IOException, ClassNotFoundException {
return decodeToObject(encodedObject, NO_OPTIONS, null);
}
/**
* Attempts to decode Base64 data and deserialize a Java Object within. Returns null
* if there was an error. If loader is not null, it will be the class loader
* used when deserializing.
*
* @param encodedObject The Base64 data to decode
* @param options Various parameters related to decoding
* @param loader Optional class loader to use in deserializing classes.
* @return The decoded and deserialized object
* @throws NullPointerException if encodedObject is null
* @throws java.io.IOException if there is a general error
* @throws ClassNotFoundException if the decoded object is of a class that cannot be found by the JVM
* @since 2.3.4
*/
public static Object decodeToObject(String encodedObject, int options, final ClassLoader loader)
throws IOException, ClassNotFoundException {
// Decode and gunzip if necessary
byte[] objBytes = decode(encodedObject, options);
ByteArrayInputStream bais = null;
ObjectInputStream ois = null;
Object obj = null;
try {
bais = new ByteArrayInputStream(objBytes);
// If no custom class loader is provided, use Java's builtin OIS.
if (loader == null) {
ois = new ObjectInputStream(bais);
} else {
// Else make a customized object input stream that uses the provided class loader.
ois = new ObjectInputStream(bais) {
@Override
public Class resolveClass(ObjectStreamClass streamClass)
throws IOException, ClassNotFoundException {
Class c = Class.forName(streamClass.getName(), false, loader);
if (c == null) {
return super.resolveClass(streamClass);
} else {
return c; // Class loader knows of this class.
}
}
};
}
obj = ois.readObject();
} catch (IOException e) {
throw e; // Catch and throw in order to execute finally{}
} catch (ClassNotFoundException e) {
throw e; // Catch and throw in order to execute finally{}
} finally {
try {
if (bais != null) {
bais.close();
}
} catch (Exception e) {
}
try {
if (ois != null) {
ois.close();
}
} catch (Exception e) {
}
}
return obj;
}
/**
* Convenience method for encoding data to a file.
*
* As of v 2.3, if there is a error,
* the method will throw an java.io.IOException. This is new to v2.3!
* In earlier versions, it just returned false, but
* in retrospect that's a pretty poor way to handle it.
*
* @param dataToEncode byte array of data to encode in base64 form
* @param filename Filename for saving encoded data
* @throws IOException if there is an error
* @throws NullPointerException if dataToEncode is null
* @since 2.1
*/
public static void encodeToFile(byte[] dataToEncode, String filename) throws IOException {
if (dataToEncode == null) {
throw new NullPointerException("Data to encode was null.");
}
Base64.OutputStream bos = null;
try {
bos = new Base64.OutputStream(new java.io.FileOutputStream(filename), Base64.ENCODE);
bos.write(dataToEncode);
} catch (IOException e) {
throw e; // Catch and throw to execute finally{} block
} finally {
try {
if (bos != null) {
bos.close();
}
} catch (Exception e) {
}
}
}
/**
* Convenience method for decoding data to a file.
*
* As of v 2.3, if there is a error, the method will throw an IOException.
* This is new to v2.3! In earlier versions, it just returned false, but
* in retrospect that's a pretty poor way to handle it.
*
* @param dataToDecode Base64-encoded data as a string
* @param filename Filename for saving decoded data
* @throws java.io.IOException if there is an error
* @since 2.1
*/
public static void decodeToFile(String dataToDecode, String filename) throws IOException {
Base64.OutputStream bos = null;
try {
bos = new Base64.OutputStream(new FileOutputStream(filename), Base64.DECODE);
bos.write(dataToDecode.getBytes(PREFERRED_ENCODING));
} catch (IOException e) {
throw e; // Catch and throw to execute finally{} block
} finally {
try {
if (bos != null) {
bos.close();
}
} catch(Exception e) {
}
}
}
/**
* Convenience method for reading a base64-encoded file and decoding it.
*
* As of v 2.3, if there is a error, the method will throw an IOException.
* This is new to v2.3! In earlier versions, it just returned false, but
* in retrospect that's a pretty poor way to handle it.
*
* @param filename Filename for reading encoded data
* @return decoded byte array
* @throws java.io.IOException if there is an error
* @since 2.1
*/
public static byte[] decodeFromFile(String filename) throws IOException {
byte[] decodedData = null;
Base64.InputStream bis = null;
try {
// Set up some useful variables
File file = new File(filename);
byte[] buffer = null;
int length = 0;
int numBytes = 0;
// Check for size of file
if (file.length() > Integer.MAX_VALUE) {
throw new IOException("File is too big for this convenience method (" + file.length() + " bytes).");
}
buffer = new byte[ (int)file.length() ];
// Open a stream
bis = new Base64.InputStream(new BufferedInputStream(new 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);
} catch (IOException e) {
throw e; // Catch and release to execute finally{}
} finally {
try {
if (bis != null) {
bis.close();
}
} catch (Exception e) {
}
}
return decodedData;
}
/**
* Convenience method for reading a binary file and base64-encoding it.
*
* As of v 2.3, if there is a error, the method will throw an java.io.IOException.
* This is new to v2.3! In earlier versions, it just returned false, but
* in retrospect that's a pretty poor way to handle it.
*
* @param filename Filename for reading binary data
* @return base64-encoded string
* @throws IOException if there is an error
* @since 2.1
*/
public static String encodeFromFile(String filename) throws IOException {
String encodedData = null;
Base64.InputStream bis = null;
try {
// Set up some useful variables
File file = new File(filename);
byte[] buffer = new byte[Math.max((int) (file.length() * 1.4 + 1), 40)]; // Need max() for math on small files (v2.2.1); Need +1 for a few corner cases (v2.3.5)
int length = 0;
int numBytes = 0;
// Open a stream
bis = new Base64.InputStream(new BufferedInputStream(new 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);
} catch (IOException e) {
throw e; // Catch and release to execute finally{}
} finally {
try {
if (bis != null) {
bis.close();
}
} catch (Exception e) {
}
}
return encodedData;
}
/**
* Reads infile and encodes it to outfile.
*
* @param infile Input file
* @param outfile Output file
* @throws java.io.IOException if there is an error
* @since 2.2
*/
public static void encodeFileToFile(String infile, String outfile) throws IOException {
String encoded = Base64.encodeFromFile(infile);
java.io.OutputStream out = null;
try {
out = new java.io.BufferedOutputStream(new FileOutputStream(outfile));
out.write(encoded.getBytes("US-ASCII")); // Strict, 7-bit output.
} catch (IOException e) {
throw e; // Catch and release to execute finally{}
} finally {
try {
if (out != null) {
out.close();
}
} catch (Exception ex) {
}
}
}
/**
* Reads infile and decodes it to outfile.
*
* @param infile Input file
* @param outfile Output file
* @throws java.io.IOException if there is an error
* @since 2.2
*/
public static void decodeFileToFile(String infile, String outfile) throws IOException {
byte[] decoded = Base64.decodeFromFile(infile);
java.io.OutputStream out = null;
try{
out = new java.io.BufferedOutputStream(new FileOutputStream(outfile));
out.write(decoded);
} catch (IOException e) {
throw e; // Catch and release to execute finally{}
} finally {
try {
if (out != null) {
out.close();
}
} catch (Exception ex) {
}
}
}
/**
* 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(InputStream in) {
this(in, DECODE);
}
/**
* 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);
}
/**
* 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 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;
} else {
return -1; // Must be end of stream
}
} else {
// Else decoding
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
}
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 IOException("Improperly padded Base64 input.");
}
}
}
// Got data?
if (position >= 0) {
// End of relevant data?
if (/*!encode &&*/ position >= numSigBytes) {
return -1;
}
if (encode && breakLines && lineLength >= MAX_LINE_LENGTH) {
lineLength = 0;
return '\n';
} else {
// This isn't important when decoding but throwing an extra "if" seems just as wasteful.
lineLength++;
int b = buffer[position++];
if (position >= bufferLength) {
position = -1;
}
return b & 0xFF; // This is how you "cast" a byte that's intended to be unsigned.
}
} else {
// Else error
throw new IOException("Error in Base64 code reading stream.");
}
}
/**
* 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 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
}
}
return i;
}
}
/**
* 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 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);
}
/**
* 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);
}
/**
* 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 IOException {
// Encoding suspended?
if (suspendEncoding) {
this.out.write(theByte);
return;
}
// 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;
}
position = 0;
}
} else {
// Else, Decoding
// 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;
}
} else if (decodabet[theByte & 0x7f] != WHITE_SPACE_ENC) {
throw new IOException("Invalid character in Base64 data.");
}
}
}
/**
* 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 IOException {
// Encoding suspended?
if (suspendEncoding) {
this.out.write(theBytes, off, len);
return;
}
for (int i = 0; i < len; i++) {
write(theBytes[off + i]);
}
}
/**
* 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 IOException {
if (position > 0) {
if (encode) {
out.write(encode3to4(b4, buffer, position, options));
position = 0;
} else {
throw new IOException("Base64 input not properly padded.");
}
}
}
/**
* Flushes and closes (I think, in the superclass) the stream.
*
* @since 1.3
*/
@Override
public void close() throws 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;
}
/**
* 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 IOException {
flushBase64();
this.suspendEncoding = true;
}
/**
* 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;
}
}
}