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Java 1.8+ Library with tons of utility classes required in all projects
/*
* Copyright (C) 2014-2024 Philip Helger (www.helger.com)
* philip[at]helger[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.helger.commons.base64;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import javax.annotation.Nonnegative;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import javax.annotation.concurrent.Immutable;
import com.helger.commons.ValueEnforcer;
import com.helger.commons.annotation.PresentForCodeCoverage;
import com.helger.commons.annotation.ReturnsMutableCopy;
import com.helger.commons.annotation.ReturnsMutableObject;
import com.helger.commons.collection.ArrayHelper;
import com.helger.commons.io.file.FileHelper;
import com.helger.commons.io.stream.NonBlockingBufferedInputStream;
import com.helger.commons.io.stream.NonBlockingBufferedOutputStream;
import com.helger.commons.io.stream.NonBlockingByteArrayInputStream;
import com.helger.commons.io.stream.NonBlockingByteArrayOutputStream;
import com.helger.commons.state.ESuccess;
/**
*
* 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 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 Philip Helger
* @version 2.3.7
*/
@Immutable
public final class Base64
{
/** 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;
/**
* Use "\r\n" instead of "\n" as newline separators. Only relevant, if option
* {@link #DO_BREAK_LINES} is also used. Value is 64.
*/
public static final int DO_NEWLINE_CRLF = 64;
/* ******** P R I V A T E F I E L D S ******** */
/** Maximum line length (76) of Base64 output. */
public static final int MAX_LINE_LENGTH = 76;
/** The equals sign (=) as a byte. */
public static final byte EQUALS_SIGN = (byte) '=';
/** The new line character (\n) as a byte. */
public static final byte NEW_LINE = (byte) '\n';
/** The new line CRLF (\r\n) as a bytes. */
private static final byte [] NEW_LINE_CRLF = new byte [] { (byte) '\r', (byte) '\n' };
/** Preferred encoding: US-ASCII */
public static final Charset PREFERRED_ENCODING = StandardCharsets.US_ASCII;
// Indicates white space in encoding
static final byte WHITE_SPACE_ENC = -5;
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
@ReturnsMutableObject
private static byte [] _getAlphabet (final int nOptions)
{
if ((nOptions & URL_SAFE) == URL_SAFE)
return _URL_SAFE_ALPHABET;
if ((nOptions & 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
@ReturnsMutableObject
static byte [] _getDecodabet (final int nOptions)
{
if ((nOptions & URL_SAFE) == URL_SAFE)
return _URL_SAFE_DECODABET;
if ((nOptions & ORDERED) == ORDERED)
return _ORDERED_DECODABET;
return _STANDARD_DECODABET;
}
@PresentForCodeCoverage
private static final Base64 INSTANCE = 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
*/
@Nonnull
@ReturnsMutableObject ("passed parameter")
static byte [] _encode3to4 (@Nonnull final byte [] b4,
@Nonnull final byte [] threeBytes,
@Nonnegative 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
@ReturnsMutableObject ("passed parameter")
static byte [] _encode3to4 (@Nonnull final byte [] source,
@Nonnegative final int srcOffset,
@Nonnegative final int numSigBytes,
@Nonnull final byte [] destination,
@Nonnegative 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);
_encode3to4 (enc4, raw3, rem, 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);
_encode3to4 (enc4, raw3, rem, NO_OPTIONS);
for (int i = 0; i < 4; i++)
{
encoded.put ((char) (enc4[i] & 0xFF));
}
}
}
/**
* 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 nOptions
* 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,
@Nonnegative final int off,
@Nonnegative final int len,
final int nOptions) throws IOException
{
final byte [] encoded = encodeBytesToBytes (source, off, len, nOptions);
// Return value according to relevant encoding.
return new String (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
@ReturnsMutableCopy
public static byte [] encodeBytesToBytes (@Nonnull final byte [] source)
{
byte [] encoded;
try
{
encoded = encodeBytesToBytes (source, 0, source.length, NO_OPTIONS);
}
catch (final IOException ex)
{
throw new IllegalStateException ("IOExceptions only come from GZipping, which is turned off", ex);
}
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 aSource
* The data to convert
* @param nOfs
* Offset in array where conversion should begin
* @param nLen
* Length of data to convert
* @param nOptions
* 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
@ReturnsMutableCopy
public static byte [] encodeBytesToBytes (@Nonnull final byte [] aSource,
@Nonnegative final int nOfs,
@Nonnegative final int nLen,
final int nOptions) throws IOException
{
ValueEnforcer.isArrayOfsLen (aSource, nOfs, nLen);
// Compress?
if ((nOptions & GZIP) != 0)
{
// GZip -> Base64 -> ByteArray
try (final NonBlockingByteArrayOutputStream baos = new NonBlockingByteArrayOutputStream ())
{
try (final Base64OutputStream b64os = new Base64OutputStream (baos, ENCODE | nOptions);
final GZIPOutputStream gzos = new GZIPOutputStream (b64os))
{
gzos.write (aSource, nOfs, nLen);
}
return baos.toByteArray ();
}
}
// Else, don't compress. Better not to use streams at all then.
{
final boolean bBreakLines = (nOptions & DO_BREAK_LINES) != 0;
final boolean bUseCRLF = (nOptions & DO_NEWLINE_CRLF) != 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.
// Bytes needed for actual encoding
int nEncLen = (nLen / 3) * 4 + (nLen % 3 > 0 ? 4 : 0);
if (bBreakLines)
{
// Plus extra newline characters
final int nLinesAdded = nEncLen / MAX_LINE_LENGTH;
if (bUseCRLF)
nEncLen += nLinesAdded * NEW_LINE_CRLF.length;
else
nEncLen += nLinesAdded;
}
final byte [] outBuff = new byte [nEncLen];
int d = 0;
int e = 0;
final int len2 = nLen - 2;
int lineLength = 0;
for (; d < len2; d += 3, e += 4)
{
_encode3to4 (aSource, d + nOfs, 3, outBuff, e, nOptions);
lineLength += 4;
if (bBreakLines && lineLength >= MAX_LINE_LENGTH)
{
if (bUseCRLF)
{
for (final byte b : NEW_LINE_CRLF)
{
outBuff[e + 4] = b;
e++;
}
}
else
{
outBuff[e + 4] = NEW_LINE;
e++;
}
lineLength = 0;
}
} // end for: each piece of array
if (d < nLen)
{
_encode3to4 (aSource, d + nOfs, nLen - d, outBuff, e, nOptions);
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
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
ValueEnforcer.notNull (source, "Source");
ValueEnforcer.notNull (destination, "Destination");
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
* @throws IOException
* In case of error
* @since 2.3.1
*/
@Nonnull
@ReturnsMutableCopy
public static byte [] decode (@Nonnull final byte [] source) throws IOException
{
return decode (source, NO_OPTIONS);
}
/**
* Low-level access to decoding ASCII characters in the form of a byte array.
* Ignores GUNZIP option, if it's set. This is not generally
* a recommended method, although it is used internally as part of the
* decoding process. Special case: if len = 0, an empty array is returned.
* Still, if you need more speed and reduced memory footprint (and aren't
* gzipping), consider this method.
*
* @param source
* The Base64 encoded data
* @param options
* Can specify options such as alphabet type to use
* @return decoded data
* @throws IOException
* In case of error
* @since 2.3.1
*/
@Nonnull
@ReturnsMutableCopy
public static byte [] decode (@Nonnull final byte [] source, final int options) throws IOException
{
return decode (source, 0, source.length, options);
}
/**
* Low-level access to decoding ASCII characters in the form of a byte array.
* Ignores GUNZIP option, if it's set. This is not generally
* a recommended method, although it is used internally as part of the
* decoding process. Special case: if len = 0, an empty array is returned.
* Still, if you need more speed and reduced memory footprint (and aren't
* gzipping), consider this method.
*
* @param aSource
* The Base64 encoded data
* @param nOfs
* The offset of where to begin decoding
* @param nLen
* The length of characters to decode
* @param nOptions
* 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
@ReturnsMutableCopy
public static byte [] decode (@Nonnull final byte [] aSource,
final int nOfs,
final int nLen,
final int nOptions) throws IOException
{
// Lots of error checking and exception throwing
ValueEnforcer.isArrayOfsLen (aSource, nOfs, nLen);
if (nLen == 0)
return ArrayHelper.EMPTY_BYTE_ARRAY;
ValueEnforcer.isTrue (nLen >= 4,
() -> "Base64-encoded string must have at least four characters, but length specified was " +
nLen);
final byte [] aDecodabet = _getDecodabet (nOptions);
// Estimate on array size
final int len34 = nLen * 3 / 4;
// Upper limit on size of output
final byte [] outBuff = new byte [len34];
// Keep track of where we're writing
int outBuffPosn = 0;
// Four byte buffer from source, eliminating white space
final byte [] b4 = new byte [4];
// Keep track of four byte input buffer
int b4Posn = 0;
// Source array counter
int i;
// Special value from DECODABET
byte sbiDecode;
for (i = nOfs; i < nOfs + nLen; i++)
{
// Loop through source
sbiDecode = aDecodabet[aSource[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++] = aSource[i]; // Save non-whitespace
if (b4Posn > 3)
{ // Time to decode?
outBuffPosn += _decode4to3 (b4, 0, outBuff, outBuffPosn, nOptions);
b4Posn = 0;
// If that was the equals sign, break out of 'for' loop
if (aSource[i] == EQUALS_SIGN)
break;
}
}
}
else
{
// There's a bad input character in the Base64 stream.
throw new IOException ("Bad Base64 input character decimal " + (aSource[i] & 0xFF) + " in array position " + i);
}
}
final byte [] aOut = new byte [outBuffPosn];
System.arraycopy (outBuff, 0, aOut, 0, outBuffPosn);
return aOut;
}
/**
* 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
@ReturnsMutableCopy
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
@ReturnsMutableCopy
public static byte [] decode (@Nonnull final String s, final int options) throws IOException
{
ValueEnforcer.notNull (s, "InputString");
byte [] bytes = s.getBytes (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.length >= 4 && !dontGunzip)
{
final int head = (bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00);
if (GZIPInputStream.GZIP_MAGIC == head)
{
try (final NonBlockingByteArrayOutputStream baos = new NonBlockingByteArrayOutputStream ();
final NonBlockingByteArrayInputStream bais = new NonBlockingByteArrayInputStream (bytes);
final GZIPInputStream gzis = new GZIPInputStream (bais))
{
final byte [] buffer = new byte [2048];
int length;
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
}
}
}
return bytes;
}
/**
* 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 aFile
* File for saving encoded data
* @return {@link ESuccess}
* @throws IOException
* if there is an error
* @throws NullPointerException
* if dataToEncode is null
* @since 2.1
*/
@Nonnull
public static ESuccess encodeToFile (@Nonnull final byte [] aDataToEncode,
@Nonnull final File aFile) throws IOException
{
ValueEnforcer.notNull (aDataToEncode, "DataToEncode");
ValueEnforcer.notNull (aFile, "File");
try (final NonBlockingBufferedOutputStream aBOS = FileHelper.getBufferedOutputStream (aFile))
{
if (aBOS == null)
return ESuccess.FAILURE;
try (final Base64OutputStream bos = new Base64OutputStream (aBOS, ENCODE))
{
bos.write (aDataToEncode);
return ESuccess.SUCCESS;
}
}
}
/**
* 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 sDataToDecode
* Base64-encoded data as a string
* @param aFile
* File for saving decoded data
* @return {@link ESuccess}
* @throws IOException
* if there is an error
* @since 2.1
*/
@Nonnull
public static ESuccess decodeToFile (@Nonnull final String sDataToDecode,
@Nonnull final File aFile) throws IOException
{
ValueEnforcer.notNull (sDataToDecode, "DataToDecode");
ValueEnforcer.notNull (aFile, "File");
try (final NonBlockingBufferedOutputStream aBOS = FileHelper.getBufferedOutputStream (aFile))
{
if (aBOS == null)
return ESuccess.FAILURE;
try (final Base64OutputStream bos = new Base64OutputStream (aBOS, DECODE))
{
bos.write (sDataToDecode.getBytes (PREFERRED_ENCODING));
return ESuccess.SUCCESS;
}
}
}
/**
* 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 sFilename
* Filename for reading encoded data
* @return decoded byte array
* @throws IOException
* if there is an error
* @since 2.1
*/
@Nonnull
@ReturnsMutableCopy
public static byte [] decodeFromFile (@Nonnull final String sFilename) throws IOException
{
// Setup some useful variables
final File aFile = new File (sFilename);
// Check for size of file
if (aFile.length () > Integer.MAX_VALUE)
throw new IOException ("File '" +
sFilename +
"' is too big for this convenience method (" +
aFile.length () +
" bytes).");
try (final NonBlockingBufferedInputStream aIS = FileHelper.getBufferedInputStream (aFile))
{
if (aIS == null)
throw new IOException ("Failed to open file '" + aFile.getAbsolutePath () + "'");
final byte [] buffer = new byte [(int) aFile.length ()];
// Open a stream
try (final Base64InputStream bis = new Base64InputStream (aIS, DECODE))
{
int nOfs = 0;
int numBytes;
// Read until done
while ((numBytes = bis.read (buffer, nOfs, 4096)) >= 0)
{
nOfs += numBytes;
}
// Save in a variable to return
final byte [] decodedData = new byte [nOfs];
System.arraycopy (buffer, 0, decodedData, 0, nOfs);
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 sFilename
* 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 sFilename) throws IOException
{
// Setup some useful variables
final File aFile = new File (sFilename);
// Check for size of file
// Need +1 for a few corner cases (v2.3.5)
final long nTargetLen = (long) (aFile.length () * 1.4) + 1;
if (nTargetLen > Integer.MAX_VALUE)
throw new IOException ("File '" +
sFilename +
"' is too big for this convenience method (" +
aFile.length () +
" bytes).");
try (final NonBlockingBufferedInputStream aIS = FileHelper.getBufferedInputStream (aFile))
{
if (aIS == null)
throw new IOException ("Failed to open file '" + aFile.getAbsolutePath () + "'");
// Open a stream
try (final Base64InputStream bis = new Base64InputStream (aIS, ENCODE))
{
// Need max() for math on small files (v2.2.1);
final byte [] aBuffer = new byte [Math.max ((int) nTargetLen, 40)];
int nLength = 0;
int nBytes;
// Read until done
while ((nBytes = bis.read (aBuffer, nLength, 4096)) >= 0)
{
nLength += nBytes;
}
// Save in a variable to return
return new String (aBuffer, 0, nLength, PREFERRED_ENCODING);
}
}
}
/**
* Reads infile and encodes it to outfile.
*
* @param infile
* Input file
* @param aFile
* Output file
* @throws IOException
* if there is an error
* @since 2.2
*/
public static void encodeFileToFile (@Nonnull final String infile, @Nonnull final File aFile) throws IOException
{
final String encoded = encodeFromFile (infile);
try (final OutputStream out = FileHelper.getBufferedOutputStream (aFile))
{
// Strict, 7-bit output.
out.write (encoded.getBytes (PREFERRED_ENCODING));
}
}
/**
* Reads infile and decodes it to outfile.
*
* @param aInFile
* Input file
* @param aOutFile
* Output file
* @throws IOException
* if there is an error
* @since 2.2
*/
public static void decodeFileToFile (@Nonnull final String aInFile, @Nonnull final File aOutFile) throws IOException
{
final byte [] decoded = decodeFromFile (aInFile);
try (final OutputStream out = FileHelper.getBufferedOutputStream (aOutFile))
{
out.write (decoded);
}
}
// ph methods
/**
* Decode the string with the default encoding (US-ASCII is the preferred
* one).
*
* @param sEncoded
* The encoded string.
* @return null if decoding failed.
*/
@Nullable
@ReturnsMutableCopy
public static byte [] safeDecode (@Nullable final String sEncoded)
{
return safeDecode (sEncoded, DONT_GUNZIP);
}
/**
* Decode the string with the default encoding (US-ASCII is the preferred
* one).
*
* @param sEncoded
* The encoded string.
* @param nOptions
* Decoding options.
* @return null if decoding failed.
*/
@Nullable
@ReturnsMutableCopy
public static byte [] safeDecode (@Nullable final String sEncoded, final int nOptions)
{
if (sEncoded != null)
try
{
return decode (sEncoded, nOptions);
}
catch (final Exception ex)
{
// fall through
}
return null;
}
/**
* Decode the byte array.
*
* @param aEncodedBytes
* The encoded byte array.
* @return null if decoding failed.
*/
@Nullable
@ReturnsMutableCopy
public static byte [] safeDecode (@Nullable final byte [] aEncodedBytes)
{
return safeDecode (aEncodedBytes, DONT_GUNZIP);
}
/**
* Decode the byte array.
*
* @param aEncodedBytes
* The encoded byte array.
* @param nOptions
* Decoding options.
* @return null if decoding failed.
*/
@Nullable
@ReturnsMutableCopy
public static byte [] safeDecode (@Nullable final byte [] aEncodedBytes, final int nOptions)
{
if (aEncodedBytes != null)
return safeDecode (aEncodedBytes, 0, aEncodedBytes.length, nOptions);
return null;
}
/**
* Decode the byte array.
*
* @param aEncodedBytes
* The encoded byte array.
* @param nOfs
* The offset of where to begin decoding
* @param nLen
* The number of characters to decode
* @return null if decoding failed.
*/
@Nullable
@ReturnsMutableCopy
public static byte [] safeDecode (@Nullable final byte [] aEncodedBytes,
@Nonnegative final int nOfs,
@Nonnegative final int nLen)
{
return safeDecode (aEncodedBytes, nOfs, nLen, DONT_GUNZIP);
}
/**
* Decode the byte array.
*
* @param aEncodedBytes
* The encoded byte array.
* @param nOfs
* The offset of where to begin decoding
* @param nLen
* The number of characters to decode
* @param nOptions
* Decoding options.
* @return null if decoding failed.
*/
@Nullable
@ReturnsMutableCopy
public static byte [] safeDecode (@Nullable final byte [] aEncodedBytes,
@Nonnegative final int nOfs,
@Nonnegative final int nLen,
final int nOptions)
{
if (aEncodedBytes != null)
try
{
return decode (aEncodedBytes, nOfs, nLen, nOptions);
}
catch (final IOException | IllegalArgumentException ex)
{
// fall through
}
return null;
}
/**
* Decode the string and convert it back to a string.
*
* @param sEncoded
* The encoded string.
* @param aCharset
* The character set to be used.
* @return null if decoding failed.
*/
@Nullable
public static String safeDecodeAsString (@Nullable final String sEncoded, @Nonnull final Charset aCharset)
{
ValueEnforcer.notNull (aCharset, "Charset");
if (sEncoded != null)
try
{
final byte [] aDecoded = decode (sEncoded, DONT_GUNZIP);
return new String (aDecoded, aCharset);
}
catch (final IOException ex)
{
// Fall through
}
return null;
}
/**
* Decode the byte array and convert it to a string.
*
* @param aEncodedBytes
* The encoded byte array.
* @param aCharset
* The character set to be used.
* @return null if decoding failed.
*/
@Nullable
public static String safeDecodeAsString (@Nullable final byte [] aEncodedBytes, @Nonnull final Charset aCharset)
{
ValueEnforcer.notNull (aCharset, "Charset");
return aEncodedBytes == null ? null : safeDecodeAsString (aEncodedBytes, 0, aEncodedBytes.length, aCharset);
}
/**
* Decode the byte array and convert it to a string.
*
* @param aEncodedBytes
* The encoded byte array.
* @param nOfs
* Offset into array
* @param nLength
* Number of bytes to decode.
* @param aCharset
* The character set to be used.
* @return null if decoding failed.
*/
@Nullable
public static String safeDecodeAsString (@Nullable final byte [] aEncodedBytes,
@Nonnegative final int nOfs,
@Nonnegative final int nLength,
@Nonnull final Charset aCharset)
{
ValueEnforcer.notNull (aCharset, "Charset");
if (aEncodedBytes != null)
try
{
final byte [] aDecoded = decode (aEncodedBytes, nOfs, nLength, DONT_GUNZIP);
return new String (aDecoded, aCharset);
}
catch (final IOException ex)
{
// Fall through
}
return null;
}
@Nullable
@ReturnsMutableCopy
public static byte [] safeEncodeBytesToBytes (@Nullable final byte [] aDecoded)
{
return safeEncodeBytesToBytes (aDecoded, NO_OPTIONS);
}
@Nullable
@ReturnsMutableCopy
public static byte [] safeEncodeBytesToBytes (@Nullable final byte [] aDecoded, final int nOptions)
{
if (aDecoded != null)
return safeEncodeBytesToBytes (aDecoded, 0, aDecoded.length, nOptions);
return null;
}
@Nullable
@ReturnsMutableCopy
public static byte [] safeEncodeBytesToBytes (@Nullable final byte [] aDecoded,
@Nonnegative final int nOfs,
@Nonnegative final int nLen)
{
return safeEncodeBytesToBytes (aDecoded, nOfs, nLen, NO_OPTIONS);
}
@Nullable
@ReturnsMutableCopy
public static byte [] safeEncodeBytesToBytes (@Nullable final byte [] aDecoded,
@Nonnegative final int nOfs,
@Nonnegative final int nLen,
final int nOptions)
{
if (aDecoded != null)
try
{
return encodeBytesToBytes (aDecoded, nOfs, nLen, nOptions);
}
catch (final IOException ex)
{
// Only on GZip which is turned off
}
return null;
}
@Nullable
@ReturnsMutableCopy
public static String safeEncodeBytes (@Nullable final byte [] aDecoded)
{
return safeEncodeBytes (aDecoded, NO_OPTIONS);
}
@Nullable
@ReturnsMutableCopy
public static String safeEncodeBytes (@Nullable final byte [] aDecoded, final int nOptions)
{
if (aDecoded != null)
return safeEncodeBytes (aDecoded, 0, aDecoded.length, nOptions);
return null;
}
@Nullable
@ReturnsMutableCopy
public static String safeEncodeBytes (@Nullable final byte [] aDecoded,
@Nonnegative final int nOfs,
@Nonnegative final int nLen)
{
return safeEncodeBytes (aDecoded, nOfs, nLen, NO_OPTIONS);
}
@Nullable
@ReturnsMutableCopy
public static String safeEncodeBytes (@Nullable final byte [] aDecoded,
@Nonnegative final int nOfs,
@Nonnegative final int nLen,
final int nOptions)
{
if (aDecoded != null)
try
{
return encodeBytes (aDecoded, nOfs, nLen, nOptions);
}
catch (final IOException ex)
{
// Only on GZip which is turned off
}
return null;
}
/**
* @param s
* The string to be encoded
* @param aCharset
* The charset to be used
* @return The encoded byte array.
*/
@Nullable
public static String safeEncode (@Nonnull final String s, @Nonnull final Charset aCharset)
{
final byte [] aDecoded = s.getBytes (aCharset);
return encodeBytes (aDecoded);
}
}