com.phloc.commons.base64.Base64 Maven / Gradle / Ivy
/**
* Copyright (C) 2006-2014 phloc systems
* http://www.phloc.com
* office[at]phloc[dot]com
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.phloc.commons.base64;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamClass;
import java.io.Serializable;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.Charset;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import javax.annotation.Nonnegative;
import javax.annotation.Nonnull;
import javax.annotation.concurrent.Immutable;
import com.phloc.commons.annotations.PresentForCodeCoverage;
import com.phloc.commons.charset.CCharset;
import com.phloc.commons.charset.CharsetManager;
import com.phloc.commons.collections.ArrayHelper;
import com.phloc.commons.io.file.FileUtils;
import com.phloc.commons.io.streams.NonBlockingByteArrayInputStream;
import com.phloc.commons.io.streams.NonBlockingByteArrayOutputStream;
import com.phloc.commons.io.streams.StreamUtils;
//ESCA-JAVA0076:
/**
*
* 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
* 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 IOException being thrown. After some discussion
* and thought, I've changed the behavior of the methods to throw 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
*/
@Immutable
public final class Base64// NOPMD
{
/* ******** P U B L I C F I E L D S ******** */
/** No options specified. Value is zero. */
public static final int NO_OPTIONS = 0;
/** Specify encoding in first bit. Value is one. */
public static final int ENCODE = 1;
/** Specify decoding in first bit. Value is zero. */
public static final int DECODE = 0;
/** Specify that data should be gzip-compressed in second bit. Value is two. */
public static final int GZIP = 2;
/** Specify that gzipped data should not be automatically gunzipped. */
public static final int DONT_GUNZIP = 4;
/** Do break lines when encoding. Value is 8. */
public static final int DO_BREAK_LINES = 8;
/**
* Encode using Base64-like encoding that is URL- and Filename-safe as
* described in Section 4 of RFC3548: http://www.faqs.org/rfcs/rfc3548.html. It is important to note that
* data encoded this way is not officially valid Base64, or at the
* very least should not be called Base64 without also specifying that is was
* encoded using the URL- and Filename-safe dialect.
*/
public static final int URL_SAFE = 16;
/**
* Encode using the special "ordered" dialect of Base64 described here: http://www.faqs.org/qa/rfcc-
* 1940. html.
*/
public static final int ORDERED = 32;
/* ******** P R I V A T E F I E L D S ******** */
/** Maximum line length (76) of Base64 output. */
private static final int MAX_LINE_LENGTH = 76;
/** The equals sign (=) as a byte. */
private static final byte EQUALS_SIGN = (byte) '=';
/** The new line character (\n) as a byte. */
private static final byte NEW_LINE = (byte) '\n';
/** Preferred encoding. */
private static final Charset PREFERRED_ENCODING = CCharset.CHARSET_US_ASCII_OBJ;
private static final byte WHITE_SPACE_ENC = -5; // Indicates white space in
// encoding
private static final byte EQUALS_SIGN_ENC = -1; // Indicates equals sign in
// encoding
/* ******** S T A N D A R D B A S E 6 4 A L P H A B E T ******** */
/** The 64 valid Base64 values. */
/*
* Host platform me be something funny like EBCDIC, so we hardcode these
* values.
*/
private static final byte [] _STANDARD_ALPHABET = { (byte) 'A',
(byte) 'B',
(byte) 'C',
(byte) 'D',
(byte) 'E',
(byte) 'F',
(byte) 'G',
(byte) 'H',
(byte) 'I',
(byte) 'J',
(byte) 'K',
(byte) 'L',
(byte) 'M',
(byte) 'N',
(byte) 'O',
(byte) 'P',
(byte) 'Q',
(byte) 'R',
(byte) 'S',
(byte) 'T',
(byte) 'U',
(byte) 'V',
(byte) 'W',
(byte) 'X',
(byte) 'Y',
(byte) 'Z',
(byte) 'a',
(byte) 'b',
(byte) 'c',
(byte) 'd',
(byte) 'e',
(byte) 'f',
(byte) 'g',
(byte) 'h',
(byte) 'i',
(byte) 'j',
(byte) 'k',
(byte) 'l',
(byte) 'm',
(byte) 'n',
(byte) 'o',
(byte) 'p',
(byte) 'q',
(byte) 'r',
(byte) 's',
(byte) 't',
(byte) 'u',
(byte) 'v',
(byte) 'w',
(byte) 'x',
(byte) 'y',
(byte) 'z',
(byte) '0',
(byte) '1',
(byte) '2',
(byte) '3',
(byte) '4',
(byte) '5',
(byte) '6',
(byte) '7',
(byte) '8',
(byte) '9',
(byte) '+',
(byte) '/' };
/**
* Translates a Base64 value to either its 6-bit reconstruction value or a
* negative number indicating some other meaning.
**/
private static final byte [] _STANDARD_DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal
// 0
// -
// 8
-5,
-5, // Whitespace: Tab and
// Linefeed
-9,
-9, // Decimal 11 - 12
-5, // Whitespace:
// Carriage Return
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 14 - 26
-9,
-9,
-9,
-9,
-9, // Decimal 27 - 31
-5, // Whitespace: Space
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 33 - 42
62, // Plus sign at
// decimal 43
-9,
-9,
-9, // Decimal 44 - 46
63, // Slash at decimal 47
52,
53,
54,
55,
56,
57,
58,
59,
60,
61, // Numbers zero
// through nine
-9,
-9,
-9, // Decimal 58 - 60
-1, // Equals sign at
// decimal 61
-9,
-9,
-9, // Decimal 62 - 64
0,
1,
2,
3,
4,
5,
6,
7,
8,
9,
10,
11,
12,
13, // Letters 'A' through
// 'N'
14,
15,
16,
17,
18,
19,
20,
21,
22,
23,
24,
25, // Letters 'O' through
// 'Z'
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 91 - 96
26,
27,
28,
29,
30,
31,
32,
33,
34,
35,
36,
37,
38, // Letters 'a' through
// 'm'
39,
40,
41,
42,
43,
44,
45,
46,
47,
48,
49,
50,
51, // Letters 'n' through
// 'z'
-9,
-9,
-9,
-9,
-9 // Decimal 123 - 127
,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 128 - 139
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 140 - 152
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 153 - 165
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 166 - 178
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 179 - 191
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 192 - 204
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 205 - 217
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 218 - 230
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 231 - 243
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9 // Decimal 244 - 255
};
/* ******** U R L S A F E B A S E 6 4 A L P H A B E T ******** */
/**
* Used in the URL- and Filename-safe dialect described in Section 4 of
* RFC3548: http://www.faqs.org
* /rfcs/rfc3548.html. Notice that the last two bytes become "hyphen" and
* "underscore" instead of "plus" and "slash."
*/
private static final byte [] _URL_SAFE_ALPHABET = { (byte) 'A',
(byte) 'B',
(byte) 'C',
(byte) 'D',
(byte) 'E',
(byte) 'F',
(byte) 'G',
(byte) 'H',
(byte) 'I',
(byte) 'J',
(byte) 'K',
(byte) 'L',
(byte) 'M',
(byte) 'N',
(byte) 'O',
(byte) 'P',
(byte) 'Q',
(byte) 'R',
(byte) 'S',
(byte) 'T',
(byte) 'U',
(byte) 'V',
(byte) 'W',
(byte) 'X',
(byte) 'Y',
(byte) 'Z',
(byte) 'a',
(byte) 'b',
(byte) 'c',
(byte) 'd',
(byte) 'e',
(byte) 'f',
(byte) 'g',
(byte) 'h',
(byte) 'i',
(byte) 'j',
(byte) 'k',
(byte) 'l',
(byte) 'm',
(byte) 'n',
(byte) 'o',
(byte) 'p',
(byte) 'q',
(byte) 'r',
(byte) 's',
(byte) 't',
(byte) 'u',
(byte) 'v',
(byte) 'w',
(byte) 'x',
(byte) 'y',
(byte) 'z',
(byte) '0',
(byte) '1',
(byte) '2',
(byte) '3',
(byte) '4',
(byte) '5',
(byte) '6',
(byte) '7',
(byte) '8',
(byte) '9',
(byte) '-',
(byte) '_' };
/**
* Used in decoding URL- and Filename-safe dialects of Base64.
*/
private static final byte [] _URL_SAFE_DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal
// 0
// -
// 8
-5,
-5, // Whitespace: Tab and
// Linefeed
-9,
-9, // Decimal 11 - 12
-5, // Whitespace:
// Carriage Return
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 14 - 26
-9,
-9,
-9,
-9,
-9, // Decimal 27 - 31
-5, // Whitespace: Space
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 33 - 42
-9, // Plus sign at
// decimal 43
-9, // Decimal 44
62, // Minus sign at
// decimal 45
-9, // Decimal 46
-9, // Slash at decimal 47
52,
53,
54,
55,
56,
57,
58,
59,
60,
61, // Numbers zero
// through nine
-9,
-9,
-9, // Decimal 58 - 60
-1, // Equals sign at
// decimal 61
-9,
-9,
-9, // Decimal 62 - 64
0,
1,
2,
3,
4,
5,
6,
7,
8,
9,
10,
11,
12,
13, // Letters 'A' through
// 'N'
14,
15,
16,
17,
18,
19,
20,
21,
22,
23,
24,
25, // Letters 'O' through
// 'Z'
-9,
-9,
-9,
-9, // Decimal 91 - 94
63, // Underscore at
// decimal 95
-9, // Decimal 96
26,
27,
28,
29,
30,
31,
32,
33,
34,
35,
36,
37,
38, // Letters 'a' through
// 'm'
39,
40,
41,
42,
43,
44,
45,
46,
47,
48,
49,
50,
51, // Letters 'n' through
// 'z'
-9,
-9,
-9,
-9,
-9 // Decimal 123 - 127
,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 128 - 139
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 140 - 152
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 153 - 165
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 166 - 178
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 179 - 191
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 192 - 204
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 205 - 217
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 218 - 230
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 231 - 243
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9 // Decimal 244 - 255
};
/* ******** O R D E R E D B A S E 6 4 A L P H A B E T ******** */
/**
* I don't get the point of this technique, but someone requested it, and it
* is described here: http://www
* .faqs.org/qa/rfcc-1940.html.
*/
private static final byte [] _ORDERED_ALPHABET = { (byte) '-',
(byte) '0',
(byte) '1',
(byte) '2',
(byte) '3',
(byte) '4',
(byte) '5',
(byte) '6',
(byte) '7',
(byte) '8',
(byte) '9',
(byte) 'A',
(byte) 'B',
(byte) 'C',
(byte) 'D',
(byte) 'E',
(byte) 'F',
(byte) 'G',
(byte) 'H',
(byte) 'I',
(byte) 'J',
(byte) 'K',
(byte) 'L',
(byte) 'M',
(byte) 'N',
(byte) 'O',
(byte) 'P',
(byte) 'Q',
(byte) 'R',
(byte) 'S',
(byte) 'T',
(byte) 'U',
(byte) 'V',
(byte) 'W',
(byte) 'X',
(byte) 'Y',
(byte) 'Z',
(byte) '_',
(byte) 'a',
(byte) 'b',
(byte) 'c',
(byte) 'd',
(byte) 'e',
(byte) 'f',
(byte) 'g',
(byte) 'h',
(byte) 'i',
(byte) 'j',
(byte) 'k',
(byte) 'l',
(byte) 'm',
(byte) 'n',
(byte) 'o',
(byte) 'p',
(byte) 'q',
(byte) 'r',
(byte) 's',
(byte) 't',
(byte) 'u',
(byte) 'v',
(byte) 'w',
(byte) 'x',
(byte) 'y',
(byte) 'z' };
/**
* Used in decoding the "ordered" dialect of Base64.
*/
private static final byte [] _ORDERED_DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal
// 0
// -
// 8
-5,
-5, // Whitespace: Tab and
// Linefeed
-9,
-9, // Decimal 11 - 12
-5, // Whitespace: Carriage
// Return
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 14 - 26
-9,
-9,
-9,
-9,
-9, // Decimal 27 - 31
-5, // Whitespace: Space
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 33 - 42
-9, // Plus sign at decimal
// 43
-9, // Decimal 44
0, // Minus sign at decimal
// 45
-9, // Decimal 46
-9, // Slash at decimal 47
1,
2,
3,
4,
5,
6,
7,
8,
9,
10, // Numbers zero through
// nine
-9,
-9,
-9, // Decimal 58 - 60
-1, // Equals sign at
// decimal 61
-9,
-9,
-9, // Decimal 62 - 64
11,
12,
13,
14,
15,
16,
17,
18,
19,
20,
21,
22,
23, // Letters 'A' through
// 'M'
24,
25,
26,
27,
28,
29,
30,
31,
32,
33,
34,
35,
36, // Letters 'N' through
// 'Z'
-9,
-9,
-9,
-9, // Decimal 91 - 94
37, // Underscore at
// decimal 95
-9, // Decimal 96
38,
39,
40,
41,
42,
43,
44,
45,
46,
47,
48,
49,
50, // Letters 'a' through
// 'm'
51,
52,
53,
54,
55,
56,
57,
58,
59,
60,
61,
62,
63, // Letters 'n' through
// 'z'
-9,
-9,
-9,
-9,
-9 // Decimal 123 - 127
,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 128 - 139
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 140 - 152
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 153 - 165
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 166 - 178
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 179 - 191
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 192 - 204
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 205 - 217
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 218 - 230
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9, // Decimal 231 - 243
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9,
-9 // Decimal 244 - 255
};
/* ******** D E T E R M I N E W H I C H A L H A B E T ******** */
/**
* Returns one of the _SOMETHING_ALPHABET byte arrays depending on the options
* specified. It's possible, though silly, to specify ORDERED and
* URLSAFE in which case one of them will be picked, though there is no
* guarantee as to which one will be picked.
*/
@Nonnull
private static byte [] _getAlphabet (final int options)
{
if ((options & URL_SAFE) == URL_SAFE)
return _URL_SAFE_ALPHABET;
if ((options & ORDERED) == ORDERED)
return _ORDERED_ALPHABET;
return _STANDARD_ALPHABET;
}
/**
* 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.
*/
@Nonnull
private static byte [] _getDecodabet (final int options)
{
if ((options & URL_SAFE) == URL_SAFE)
return _URL_SAFE_DECODABET;
if ((options & ORDERED) == ORDERED)
return _ORDERED_DECODABET;
return _STANDARD_DECODABET;
}
@PresentForCodeCoverage
@SuppressWarnings ("unused")
private static final Base64 s_aInstance = new Base64 ();
/** Defeats instantiation. */
private Base64 ()
{}
/* ******** E N C O D I N G M E T H O D S ******** */
/**
* Encodes up to the first three bytes of array threeBytes and
* returns a four-byte array in Base64 notation. The actual number of
* significant bytes in your array is given by numSigBytes. The
* array threeBytes needs only be as big as numSigBytes.
* Code can reuse a byte array by passing a four-byte array as b4.
*
* @param b4
* A reusable byte array to reduce array instantiation
* @param threeBytes
* the array to convert
* @param numSigBytes
* the number of significant bytes in your array
* @return four byte array in Base64 notation.
* @since 1.5.1
*/
private static byte [] _encode3to4 (final byte [] b4,
final byte [] threeBytes,
final int numSigBytes,
final int options)
{
_encode3to4 (threeBytes, 0, numSigBytes, b4, 0, options);
return b4;
}
/**
*
* 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
*/
@Nonnull
private static byte [] _encode3to4 (@Nonnull final byte [] source,
final int srcOffset,
final int numSigBytes,
@Nonnull final byte [] destination,
final int destOffset,
final int options)
{
final byte [] aAlphabet = _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] = aAlphabet[(inBuff >>> 18)];
destination[destOffset + 1] = aAlphabet[(inBuff >>> 12) & 0x3f];
destination[destOffset + 2] = aAlphabet[(inBuff >>> 6) & 0x3f];
destination[destOffset + 3] = aAlphabet[(inBuff) & 0x3f];
return destination;
case 2:
destination[destOffset] = aAlphabet[(inBuff >>> 18)];
destination[destOffset + 1] = aAlphabet[(inBuff >>> 12) & 0x3f];
destination[destOffset + 2] = aAlphabet[(inBuff >>> 6) & 0x3f];
destination[destOffset + 3] = EQUALS_SIGN;
return destination;
case 1:
destination[destOffset] = aAlphabet[(inBuff >>> 18)];
destination[destOffset + 1] = aAlphabet[(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 (@Nonnull final ByteBuffer raw, @Nonnull final ByteBuffer encoded)
{
final byte [] raw3 = new byte [3];
final byte [] enc4 = new byte [4];
while (raw.hasRemaining ())
{
final 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 (@Nonnull final ByteBuffer raw, @Nonnull final CharBuffer encoded)
{
final byte [] raw3 = new byte [3];
final byte [] enc4 = new byte [4];
while (raw.hasRemaining ())
{
final 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 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 IOException
* if there is an error
* @throws NullPointerException
* if serializedObject is null
* @since 1.4
*/
public static String encodeObject (@Nonnull final 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 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 IOException
* if there is an error
* @since 2.0
*/
@Nonnull
public static String encodeObject (@Nonnull final Serializable serializableObject, final int options) throws IOException
{
if (serializableObject == null)
throw new NullPointerException ("Cannot serialize a null object.");
// Streams
NonBlockingByteArrayOutputStream baos = null;
java.io.OutputStream b64os = null;
GZIPOutputStream gzos = null;
ObjectOutputStream oos = null;
try
{
// ObjectOutputStream -> (GZIP) -> Base64 -> ByteArrayOutputStream
baos = new NonBlockingByteArrayOutputStream ();
b64os = new Base64.OutputStream (baos, ENCODE | options);
if ((options & GZIP) != 0)
{
// Gzip
gzos = new GZIPOutputStream (b64os);
oos = new ObjectOutputStream (gzos);
}
else
{
// Not gzipped
oos = new ObjectOutputStream (b64os);
}
oos.writeObject (serializableObject);
}
finally
{
StreamUtils.close (oos);
StreamUtils.close (gzos);
StreamUtils.close (b64os);
StreamUtils.close (baos);
}
// Return value according to relevant encoding.
return CharsetManager.getAsString (baos.toByteArray (), PREFERRED_ENCODING);
}
/**
* 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
*/
@Nonnull
public static String encodeBytes (@Nonnull final 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 (final 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 options
* Specified options
* @return The Base64-encoded data as a String
* @see Base64#GZIP
* @see Base64#DO_BREAK_LINES
* @throws IOException
* if there is an error
* @throws NullPointerException
* if source array is null
* @since 2.0
*/
@Nonnull
public static String encodeBytes (@Nonnull final byte [] source, final 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 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
*/
@Nonnull
public static String encodeBytes (@Nonnull final byte [] source, final int off, final 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 (final 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 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
*/
@Nonnull
public static String encodeBytes (@Nonnull final byte [] source, final int off, final int len, final int options) throws IOException
{
final byte [] encoded = encodeBytesToBytes (source, off, len, options);
// Return value according to relevant encoding.
return CharsetManager.getAsString (encoded, PREFERRED_ENCODING);
}
/**
* 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
*/
@Nonnull
public static byte [] encodeBytesToBytes (@Nonnull final byte [] source)
{
byte [] encoded;
try
{
encoded = encodeBytesToBytes (source, 0, source.length, Base64.NO_OPTIONS);
}
catch (final IOException ex)
{
assert false : "IOExceptions only come from GZipping, which is turned off: " + ex.getMessage ();
encoded = null;
}
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 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
*/
@Nonnull
public static byte [] encodeBytesToBytes (@Nonnull final byte [] source,
final int off,
final int len,
final int options) throws IOException// NOPMD
{
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",
Integer.valueOf (off),
Integer.valueOf (len),
Integer.valueOf (source.length)));
// Compress?
if ((options & GZIP) != 0)
{
NonBlockingByteArrayOutputStream baos = null;
GZIPOutputStream gzos = null;
Base64.OutputStream b64os = null;
try
{
// GZip -> Base64 -> ByteArray
baos = new NonBlockingByteArrayOutputStream ();
b64os = new Base64.OutputStream (baos, ENCODE | options);
gzos = new GZIPOutputStream (b64os);
gzos.write (source, off, len);
gzos.close ();
}
finally
{
StreamUtils.close (gzos);
StreamUtils.close (b64os);
StreamUtils.close (baos);
}
return baos.toByteArray ();
}
// Else, don't compress. Better not to use streams at all then.
{
final 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
}
final byte [] outBuff = new byte [encLen];
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;
}
} // en dfor: each piece of array
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.
final byte [] finalOut = new byte [e];
System.arraycopy (outBuff, 0, finalOut, 0, e);
// System.err.println("Having to resize array from " + outBuff.length +
// " to " + e );
return finalOut;
}
// System.err.println("No need to resize array.");
return outBuff;
}
}
/* ******** 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
* @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
*/
@Nonnegative
private static int _decode4to3 (@Nonnull final byte [] source,
final int srcOffset,
@Nonnull final byte [] destination,
final int destOffset,
final 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 ("Source array with length " +
source.length +
" cannot have offset of " +
srcOffset +
" and still process four bytes.");
}
if (destOffset < 0 || destOffset + 2 >= destination.length)
{
throw new IllegalArgumentException ("Destination array with length " +
destination.length +
" cannot have offset of " +
destOffset +
" and still store three bytes.");
}
final byte [] aDecodabet = _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 = ((aDecodabet[source[srcOffset]] & 0xFF) << 18) |
((aDecodabet[source[srcOffset + 1]] & 0xFF) << 12);
destination[destOffset] = (byte) (outBuff >>> 16);
return 1;
}
// Example: DkL=
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 = ((aDecodabet[source[srcOffset]] & 0xFF) << 18) |
((aDecodabet[source[srcOffset + 1]] & 0xFF) << 12) |
((aDecodabet[source[srcOffset + 2]] & 0xFF) << 6);
destination[destOffset] = (byte) (outBuff >>> 16);
destination[destOffset + 1] = (byte) (outBuff >>> 8);
return 2;
}
// 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 );
final int outBuff = ((aDecodabet[source[srcOffset]] & 0xFF) << 18) |
((aDecodabet[source[srcOffset + 1]] & 0xFF) << 12) |
((aDecodabet[source[srcOffset + 2]] & 0xFF) << 6) |
((aDecodabet[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
*/
@Nonnull
public static byte [] decode (@Nonnull final byte [] source) throws IOException
{
byte [] decoded;
// 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
*/
@Nonnull
public static byte [] decode (@Nonnull final byte [] source, final int off, final int len, final 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 ("Source array with length " +
source.length +
" cannot have offset of " +
off +
" and process " +
len +
" bytes.");
}
if (len == 0)
return ArrayHelper.EMPTY_BYTE_ARRAY;
if (len < 4)
{
throw new IllegalArgumentException ("Base64-encoded string must have at least four characters, but length specified was " +
len);
}
final byte [] aDecodabet = _getDecodabet (options);
final int len34 = len * 3 / 4; // Estimate on array size
final byte [] outBuff = new byte [len34]; // Upper limit on size of output
int outBuffPosn = 0; // Keep track of where we're writing
final 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; // Source array counter
byte sbiDecode; // Special value from DECODABET
for (i = off; i < off + len; i++)
{
// Loop through source
sbiDecode = aDecodabet[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;
}
}
}
else
{
// There's a bad input character in the Base64 stream.
throw new IOException ("Bad Base64 input character decimal " + (source[i] & 0xFF) + " in array position " + i);
}
} // each input character
final 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
*/
@Nonnull
public static byte [] decode (@Nonnull final 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
*/
@Nonnull
public static byte [] decode (@Nonnull final String s, final int options) throws IOException
{
if (s == null)
throw new NullPointerException ("Input string was null.");
byte [] bytes = CharsetManager.getAsBytes (s, PREFERRED_ENCODING);
//
// Decode
bytes = decode (bytes, 0, bytes.length, options);
// Check to see if it's gzip-compressed
// GZIP Magic Two-Byte Number: 0x8b1f (35615)
final boolean dontGunzip = (options & DONT_GUNZIP) != 0;
if ((bytes != null) && (bytes.length >= 4) && (!dontGunzip))
{
final int head = (bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00);
if (GZIPInputStream.GZIP_MAGIC == head)
{
NonBlockingByteArrayInputStream bais = null;
GZIPInputStream gzis = null;
NonBlockingByteArrayOutputStream baos = null;
final byte [] buffer = new byte [2048];
int length;
try
{
baos = new NonBlockingByteArrayOutputStream ();
bais = new NonBlockingByteArrayInputStream (bytes);
gzis = new GZIPInputStream (bais);
while ((length = gzis.read (buffer)) >= 0)
{
baos.write (buffer, 0, length);
}
// No error? Get new bytes.
bytes = baos.toByteArray ();
}
catch (final IOException e)
{
// Just return originally-decoded bytes
}
finally
{
StreamUtils.close (baos);
StreamUtils.close (gzis);
StreamUtils.close (bais);
}
}
}
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 (@Nonnull final 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 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 (@Nonnull final String encodedObject, final int options, final ClassLoader loader) throws IOException,
java.lang.ClassNotFoundException
{
// Decode and gunzip if necessary
final byte [] objBytes = decode (encodedObject, options);
NonBlockingByteArrayInputStream bais = null;
ObjectInputStream ois = null;
Object obj = null;
try
{
bais = new NonBlockingByteArrayInputStream (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 (final ObjectStreamClass streamClass) throws IOException,
ClassNotFoundException
{
final Class c = Class.forName (streamClass.getName (), false, loader);
if (c != null)
return c;
return super.resolveClass (streamClass);
}
};
}
obj = ois.readObject ();
}
finally
{
StreamUtils.close (bais);
StreamUtils.close (ois);
}
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 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 aDataToEncode
* byte array of data to encode in base64 form
* @param sFilename
* 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 (@Nonnull final byte [] aDataToEncode, final String sFilename) throws IOException
{
if (aDataToEncode == null)
throw new NullPointerException ("Data to encode was null.");
Base64.OutputStream bos = null;
try
{
bos = new Base64.OutputStream (FileUtils.getOutputStream (sFilename), Base64.ENCODE);
bos.write (aDataToEncode);
}
finally
{
StreamUtils.close (bos);
}
}
/**
* 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 IOException
* if there is an error
* @since 2.1
*/
public static void decodeToFile (@Nonnull final String dataToDecode, @Nonnull final String filename) throws IOException
{
Base64.OutputStream bos = null;
try
{
bos = new Base64.OutputStream (FileUtils.getOutputStream (filename), Base64.DECODE);
bos.write (CharsetManager.getAsBytes (dataToDecode, PREFERRED_ENCODING));
}
finally
{
StreamUtils.close (bos);
}
}
/**
* 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 IOException
* if there is an error
* @since 2.1
*/
@Nonnull
public static byte [] decodeFromFile (@Nonnull final String filename) throws IOException
{
byte [] decodedData;
Base64.InputStream bis = null;
try
{
// Set up some useful variables
final File file = new File (filename);
byte [] buffer;
int length = 0;
int numBytes;
// 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 (StreamUtils.getBuffered (FileUtils.getInputStream (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);
}
finally
{
StreamUtils.close (bis);
}
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 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
*/
@Nonnull
public static String encodeFromFile (@Nonnull final String filename) throws IOException
{
String encodedData = null;
Base64.InputStream bis = null;
try
{
// Set up some useful variables
final File file = new File (filename);
// Need max() for math on small files (v2.2.1);
// Need +1 for a few corner cases (v2.3.5)
final byte [] buffer = new byte [Math.max ((int) (file.length () * 1.4 + 1), 40)];
int length = 0;
int numBytes;
// Open a stream
bis = new Base64.InputStream (StreamUtils.getBuffered (FileUtils.getInputStream (file)), Base64.ENCODE);
// Read until done
while ((numBytes = bis.read (buffer, length, 4096)) >= 0)
{
length += numBytes;
}
// Save in a variable to return
encodedData = CharsetManager.getAsString (buffer, 0, length, Base64.PREFERRED_ENCODING);
}
finally
{
StreamUtils.close (bis);
}
return encodedData;
}
/**
* Reads infile and encodes it to outfile.
*
* @param infile
* Input file
* @param outfile
* Output file
* @throws IOException
* if there is an error
* @since 2.2
*/
public static void encodeFileToFile (@Nonnull final String infile, @Nonnull final String outfile) throws IOException
{
final String encoded = Base64.encodeFromFile (infile);
java.io.OutputStream out = null;
try
{
out = new BufferedOutputStream (FileUtils.getOutputStream (outfile));
// Strict, 7-bit output.
out.write (CharsetManager.getAsBytes (encoded, PREFERRED_ENCODING));
}
finally
{
StreamUtils.close (out);
}
}
/**
* Reads infile and decodes it to outfile.
*
* @param infile
* Input file
* @param outfile
* Output file
* @throws IOException
* if there is an error
* @since 2.2
*/
public static void decodeFileToFile (@Nonnull final String infile, @Nonnull final String outfile) throws IOException
{
final byte [] decoded = Base64.decodeFromFile (infile);
java.io.OutputStream out = null;
try
{
out = new BufferedOutputStream (FileUtils.getOutputStream (outfile));
out.write (decoded);
}
finally
{
StreamUtils.close (out);
}
}
/* ******** I N N E R C L A S S I N P U T S T R E A M ******** */
/**
* A {@link Base64.InputStream} will read data from another
* java.io.InputStream, given in the constructor, and encode/decode
* to/from Base64 notation on the fly.
*
* @see Base64
* @since 1.3
*/
public static class InputStream extends java.io.FilterInputStream
{
private final boolean m_bEncode; // Encoding or decoding
private int m_nPosition; // Current position in the buffer
private final byte [] m_aBuffer; // Small buffer holding converted data
private final int m_nBufferLength; // Length of buffer (3 or 4)
private int m_nNumSigBytes; // Number of meaningful bytes in the buffer
private int m_nLineLength;
private final boolean m_bBreakLines; // Break lines at less than 80
// characters
private final int m_nOptions; // Record options used to create the stream.
private final byte [] m_aDecodabet; // Local copies to avoid extra method
// calls
/**
* Constructs a {@link Base64.InputStream} in DECODE mode.
*
* @param pin
* the java.io.InputStream from which to read data.
* @since 1.3
*/
public InputStream (final java.io.InputStream pin)
{
this (pin, 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 pin
* the java.io.InputStream from which to read data.
* @param poptions
* Specified options
* @see Base64#ENCODE
* @see Base64#DECODE
* @see Base64#DO_BREAK_LINES
* @since 2.0
*/
public InputStream (final java.io.InputStream pin, final int poptions)
{
super (pin);
this.m_nOptions = poptions; // Record for later
this.m_bBreakLines = (poptions & DO_BREAK_LINES) > 0;
this.m_bEncode = (poptions & ENCODE) > 0;
this.m_nBufferLength = m_bEncode ? 4 : 3;
this.m_aBuffer = new byte [m_nBufferLength];
this.m_nPosition = -1;
this.m_nLineLength = 0;
this.m_aDecodabet = _getDecodabet (poptions);
}
/**
* 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// NOPMD
{
// Do we need to get data?
if (m_nPosition < 0)
{
if (m_bEncode)
{
final byte [] b3 = new byte [3];
int numBinaryBytes = 0;
for (int i = 0; i < 3; i++)
{
final int b = in.read ();
// If end of stream, b is -1.
if (b < 0)
break;
b3[i] = (byte) b;
numBinaryBytes++;
}
if (numBinaryBytes > 0)
{
_encode3to4 (b3, 0, numBinaryBytes, m_aBuffer, 0, m_nOptions);
m_nPosition = 0;
m_nNumSigBytes = 4;
}
else
{
return -1; // Must be end of stream
}
}
// Else decoding
else
{
final byte [] b4 = new byte [4];
int i;
for (i = 0; i < 4; i++)
{
// Read four "meaningful" bytes:
int b;
do
{
b = in.read ();
} while (b >= 0 && m_aDecodabet[b & 0x7f] <= WHITE_SPACE_ENC);
if (b < 0)
break; // Reads a -1 if end of stream
b4[i] = (byte) b;
}
if (i == 4)
{
m_nNumSigBytes = _decode4to3 (b4, 0, m_aBuffer, 0, m_nOptions);
m_nPosition = 0;
}
else
if (i == 0)
{
return -1;
}
else
{
// Must have broken out from above.
throw new IOException ("Improperly padded Base64 input.");
} // end
}
}
// Got data?
if (m_nPosition >= 0)
{
if ( /* !encode && */m_nPosition >= m_nNumSigBytes)
{
return -1;
}
if (m_bEncode && m_bBreakLines && m_nLineLength >= MAX_LINE_LENGTH)
{
m_nLineLength = 0;
return '\n';
}
{
m_nLineLength++; // This isn't important when decoding
// but throwing an extra "if" seems
// just as wasteful.
final int b = m_aBuffer[m_nPosition++];
if (m_nPosition >= m_nBufferLength)
m_nPosition = -1;
return b & 0xFF; // This is how you "cast" a byte that's
// intended to be unsigned.
}
}
// 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 (final byte [] dest, final int off, final 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
} // Out of 'for' loop
}
return i;
}
}
/* ******** I N N E R C L A S S O U T P U T S T R E A M ******** */
/**
* A {@link Base64.OutputStream} will write data to another
* java.io.OutputStream, given in the constructor, and encode/decode
* to/from Base64 notation on the fly.
*
* @see Base64
* @since 1.3
*/
public static class OutputStream extends java.io.FilterOutputStream
{
private final boolean m_bEncode;
private int m_nPosition;
private byte [] m_aBuffer;
private final int m_nBufferLength;
private int m_nLineLength;
private final boolean m_bBreakLines;
private final byte [] m_aB4; // Scratch used in a few places
private boolean m_bSuspendEncoding;
private final int m_nOptions; // Record for later
private final byte [] m_aDecodabet; // Local copies to avoid extra method
// calls
/**
* Constructs a {@link Base64.OutputStream} in ENCODE mode.
*
* @param pout
* the java.io.OutputStream to which data will be written.
* @since 1.3
*/
public OutputStream (final java.io.OutputStream pout)
{
this (pout, 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 pout
* the java.io.OutputStream to which data will be written.
* @param poptions
* Specified options.
* @see Base64#ENCODE
* @see Base64#DECODE
* @see Base64#DO_BREAK_LINES
* @since 1.3
*/
public OutputStream (final java.io.OutputStream pout, final int poptions)
{
super (pout);
this.m_bBreakLines = (poptions & DO_BREAK_LINES) != 0;
this.m_bEncode = (poptions & ENCODE) != 0;
this.m_nBufferLength = m_bEncode ? 3 : 4;
this.m_aBuffer = new byte [m_nBufferLength];
this.m_nPosition = 0;
this.m_nLineLength = 0;
this.m_bSuspendEncoding = false;
this.m_aB4 = new byte [4];
this.m_nOptions = poptions;
this.m_aDecodabet = _getDecodabet (poptions);
}
/**
* 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 IOException
{
// Encoding suspended?
if (m_bSuspendEncoding)
{
this.out.write (theByte);
return;
}
// Encode?
if (m_bEncode)
{
m_aBuffer[m_nPosition++] = (byte) theByte;
if (m_nPosition >= m_nBufferLength)
{ // Enough to encode.
this.out.write (_encode3to4 (m_aB4, m_aBuffer, m_nBufferLength, m_nOptions));
m_nLineLength += 4;
if (m_bBreakLines && m_nLineLength >= MAX_LINE_LENGTH)
{
this.out.write (NEW_LINE);
m_nLineLength = 0;
}
m_nPosition = 0;
}
}
// Else, Decoding
else
{
// Meaningful Base64 character?
if (m_aDecodabet[theByte & 0x7f] > WHITE_SPACE_ENC)
{
m_aBuffer[m_nPosition++] = (byte) theByte;
if (m_nPosition >= m_nBufferLength)
{ // Enough to output.
final int len = Base64._decode4to3 (m_aBuffer, 0, m_aB4, 0, m_nOptions);
out.write (m_aB4, 0, len);
m_nPosition = 0;
}
}
else
if (m_aDecodabet[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 (final byte [] theBytes, final int off, final int len) throws IOException
{
// Encoding suspended?
if (m_bSuspendEncoding)
{
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 IOException
* if there's an error.
*/
public void flushBase64 () throws IOException
{
if (m_nPosition > 0)
{
if (m_bEncode)
{
out.write (_encode3to4 (m_aB4, m_aBuffer, m_nPosition, m_nOptions));
m_nPosition = 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.
if (out != null)
super.close ();
m_aBuffer = 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 IOException
* if there's an error flushing
* @since 1.5.1
*/
public void suspendEncoding () throws IOException
{
flushBase64 ();
this.m_bSuspendEncoding = 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.m_bSuspendEncoding = false;
}
}
}