Java tutorial
/** * Encodes and decodes to and from Base64 notation. * * <p> * Homepage: <a href="http://iharder.net/base64">http://iharder.net/base64</a>. * </p> * * <p> * Change Log: * </p> * <ul> * <li>v2.2.1 - Fixed bug using URL_SAFE and ORDERED encodings. Fixed bug * when using very small files (~< 40 bytes).</li> * <li>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: * <ol> * <li>The default is RFC3548 format.</li> * <li>Using Base64.URLSAFE generates URL and file name friendly format as * described in Section 4 of RFC3548. * http://www.faqs.org/rfcs/rfc3548.html</li> * <li>Using Base64.ORDERED generates URL and file name friendly format * that preserves lexical ordering as described in * http://www.faqs.org/qa/rfcc-1940.html</li> * </ol> * <p> * Special thanks to Jim Kellerman at <a href="http://www.powerset.com/"> * http://www.powerset.com/</a> for contributing the new Base64 dialects. * </li> * * <li>v2.1 - Cleaned up javadoc comments and unused variables and methods. * Added some convenience methods for reading and writing to and from files. * </li> * <li>v2.0.2 - Now specifies UTF-8 encoding in places where the code fails on * systems with other encodings (like EBCDIC).</li> * <li>v2.0.1 - Fixed an error when decoding a single byte, that is, when the * encoded data was a single byte.</li> * <li>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 (<tt>int</tt>s that you "OR" together).</li> * <li>v1.5.1 - Fixed bug when decompressing and decoding to a byte[] using * <tt>decode( String s, boolean gzipCompressed )</tt>. 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).</li> * <li>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.</li> * <li>v1.4 - Added helper methods to read/write files.</li> * <li>v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.</li> * <li>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.</li> * <li>v1.3.4 - Fixed when "improperly padded stream" error was thrown at the * wrong time.</li> * <li>v1.3.3 - Fixed I/O streams which were totally messed up.</li> * </ul> * * <p> * 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! * <p> * Please visit <a href="http://iharder.net/base64">http://iharder.net/base64</a> * periodically to check for updates or to contribute improvements. * <p> * author: Robert Harder, rob@iharder.net * <br> * version: 2.2.1 */ /** * Copyright 2007 The Apache Software Foundation * * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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 agilejson; import java.io.BufferedInputStream; import java.io.BufferedOutputStream; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.FilterInputStream; import java.io.FilterOutputStream; import java.io.InputStream; import java.io.IOException; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.OutputStream; import java.io.Serializable; import java.io.UnsupportedEncodingException; import java.lang.ClassNotFoundException; import java.util.zip.GZIPInputStream; import java.util.zip.GZIPOutputStream; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * Encodes and decodes to and from Base64 notation. */ public class Base64 { /* ******** P U B L I C F I E L D S ******** */ /** No options specified. Value is zero. */ public final static int NO_OPTIONS = 0; /** Specify encoding. */ public final static int ENCODE = 1; /** Specify decoding. */ public final static int DECODE = 0; /** Specify that data should be gzip-compressed. */ public final static int GZIP = 2; /** Don't break lines when encoding (violates strict Base64 specification) */ public final static int DONT_BREAK_LINES = 8; /** * Encode using Base64-like encoding that is URL and Filename safe as * described in Section 4 of RFC3548: * <a href="http://www.faqs.org/rfcs/rfc3548.html"> * http://www.faqs.org/rfcs/rfc3548.html</a>. * It is important to note that data encoded this way is <em>not</em> * officially valid Base64, or at the very least should not be called Base64 * without also specifying that is was encoded using the URL and * Filename safe dialect. */ public final static int URL_SAFE = 16; /** * Encode using the special "ordered" dialect of Base64 described here: * <a href="http://www.faqs.org/qa/rfcc-1940.html"> * http://www.faqs.org/qa/rfcc-1940.html</a>. */ public final static int ORDERED = 32; /* ******** P R I V A T E F I E L D S ******** */ private static final Log LOG = LogFactory.getLog(Base64.class); /** Maximum line length (76) of Base64 output. */ private final static int MAX_LINE_LENGTH = 76; /** The equals sign (=) as a byte. */ private final static byte EQUALS_SIGN = (byte) '='; /** The new line character (\n) as a byte. */ private final static byte NEW_LINE = (byte) '\n'; /** Preferred encoding. */ private final static String PREFERRED_ENCODING = "UTF-8"; private final static byte WHITE_SPACE_ENC = -5; // Indicates white space private final static byte EQUALS_SIGN_ENC = -1; // Indicates equals sign /* ******** 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 may be something funny like EBCDIC, so we hardcode these * values. */ private final static byte[] _STANDARD_ALPHABET = { (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G', (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z', (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '+', (byte) '/' }; /** * Translates a Base64 value to either its 6-bit reconstruction value or a * negative number indicating some other meaning. */ private final static byte[] _STANDARD_DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8 -5, -5, // Whitespace: Tab, Newline -9, -9, // Decimal 11 - 12 -5, // Whitespace: 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 - 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' - 'N' 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' - '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' - 'm' 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' -'z' -9, -9, -9, -9 // Decimal 123 - 126 }; /* ******** 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 * <a href="http://www.faqs.org/rfcs/rfc3548.html"> * http://www.faqs.org/rfcs/rfc3548.html</a>. * Notice that the last two bytes become "hyphen" and "underscore" instead of * "plus" and "slash." */ private final static byte[] _URL_SAFE_ALPHABET = { (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G', (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z', (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '-', (byte) '_' }; /** * Used in decoding URL and Filename safe dialects of Base64. */ private final static byte[] _URL_SAFE_DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8 -5, -5, // Whitespace: Tab, Newline -9, -9, // Decimal 11 - 12 -5, // Whitespace: 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 43 -9, // Decimal 44 62, // Minus sign at 45 -9, // Decimal 46 -9, // Slash at 47 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers 0 - 9 -9, -9, -9, // Decimal 58 - 60 -1, // Equals sign at 61 -9, -9, -9, // Decimal 62 - 64 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' - 'N' 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' - 'Z' -9, -9, -9, -9, // Decimal 91 - 94 63, // Underscore at 95 -9, // Decimal 96 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' - 'm' 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' - 'z' -9, -9, -9, -9 // Decimal 123 - 126 }; /* ******** O R D E R E D B A S E 6 4 A L P H A B E T ******** */ /** * In addition to being URL and file name friendly, this encoding preserves * the sort order of encoded values. Whatever is input, be it string or * just an array of bytes, when you use this encoding, the encoded value sorts * exactly the same as the input value. It is described in the RFC change * request: <a href="http://www.faqs.org/qa/rfcc-1940.html"> * http://www.faqs.org/qa/rfcc-1940.html</a>. * * It replaces "plus" and "slash" with "hyphen" and "underscore" and * rearranges the alphabet so that the characters are in their natural sort * order. */ private final static byte[] _ORDERED_ALPHABET = { (byte) '-', (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5', (byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G', (byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N', (byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U', (byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z', (byte) '_', (byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g', (byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n', (byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u', (byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z' }; /** * Used in decoding the "ordered" dialect of Base64. */ private final static byte[] _ORDERED_DECODABET = { -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8 -5, -5, // Whitespace: Tab, Newline -9, -9, // Decimal 11 - 12 -5, // Whitespace: 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 43 -9, // Decimal 44 0, // Minus sign at 45 -9, // Decimal 46 -9, // Slash at decimal 47 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, // Numbers 0 - 9 -9, -9, -9, // Decimal 58 - 60 -1, // Equals sign at 61 -9, -9, -9, // Decimal 62 - 64 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, // Letters 'A' - 'M' 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, // Letters 'N' - 'Z' -9, -9, -9, -9, // Decimal 91 - 94 37, // Underscore at 95 -9, // Decimal 96 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, // Letters 'a' - 'm' 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, // Letters 'n' - 'z' -9, -9, -9, -9 // Decimal 123 - 126 }; /* ******** 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. */ protected final static byte[] getAlphabet(int options) { if ((options & URL_SAFE) == URL_SAFE) { return _URL_SAFE_ALPHABET; } else if ((options & ORDERED) == ORDERED) { return _ORDERED_ALPHABET; } else { return _STANDARD_ALPHABET; } } // end getAlphabet /** * Returns one of the _SOMETHING_DECODABET byte arrays depending on the * options specified. It's possible, though silly, to specify ORDERED and * URL_SAFE in which case one of them will be picked, though there is no * guarantee as to which one will be picked. */ protected final static byte[] getDecodabet(int options) { if ((options & URL_SAFE) == URL_SAFE) { return _URL_SAFE_DECODABET; } else if ((options & ORDERED) == ORDERED) { return _ORDERED_DECODABET; } else { return _STANDARD_DECODABET; } } // end getDecodabet /** Defeats instantiation. */ private Base64() { } /** * Main program. Used for testing. * * Encodes or decodes two files from the command line * * @param args command arguments */ public final static void main(String[] args) { if (args.length < 3) { usage("Not enough arguments."); } else { String flag = args[0]; String infile = args[1]; String outfile = args[2]; if (flag.equals("-e")) { // encode encodeFileToFile(infile, outfile); } else if (flag.equals("-d")) { // decode decodeFileToFile(infile, outfile); } else { usage("Unknown flag: " + flag); } } } // end main /** * Prints command line usage. * * @param msg A message to include with usage info. */ private final static void usage(String msg) { System.err.println(msg); System.err.println("Usage: java Base64 -e|-d inputfile outputfile"); } // end usage /* ******** E N C O D I N G M E T H O D S ******** */ /** * Encodes up to the first three bytes of array <var>threeBytes</var> and * returns a four-byte array in Base64 notation. The actual number of * significant bytes in your array is given by <var>numSigBytes</var>. The * array <var>threeBytes</var> needs only be as big as <var>numSigBytes</var>. * Code can reuse a byte array by passing a four-byte array as <var>b4</var>. * * @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 */ protected static byte[] encode3to4(byte[] b4, byte[] threeBytes, int numSigBytes, int options) { encode3to4(threeBytes, 0, numSigBytes, b4, 0, options); return b4; } // end encode3to4 /** * Encodes up to three bytes of the array <var>source</var> and writes the * resulting four Base64 bytes to <var>destination</var>. The source and * destination arrays can be manipulated anywhere along their length by * specifying <var>srcOffset</var> and <var>destOffset</var>. This method * does not check to make sure your arrays are large enough to accomodate * <var>srcOffset</var> + 3 for the <var>source</var> array or * <var>destOffset</var> + 4 for the <var>destination</var> array. The * actual number of significant bytes in your array is given by * <var>numSigBytes</var>. * <p> * 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 <var>destination</var> array * @since 1.3 */ protected static byte[] encode3to4(byte[] source, int srcOffset, int numSigBytes, byte[] destination, int destOffset, int options) { byte[] ALPHABET = getAlphabet(options); // 1 2 3 // 01234567890123456789012345678901 Bit position // --------000000001111111122222222 Array position from threeBytes // --------| || || || | Six bit groups to index ALPHABET // >>18 >>12 >> 6 >> 0 Right shift necessary // 0x3f 0x3f 0x3f Additional AND // Create buffer with zero-padding if there are only one or two // significant bytes passed in the array. // We have to shift left 24 in order to flush out the 1's that appear // when Java treats a value as negative that is cast from a byte to an int. int inBuff = (numSigBytes > 0 ? ((source[srcOffset] << 24) >>> 8) : 0) | (numSigBytes > 1 ? ((source[srcOffset + 1] << 24) >>> 16) : 0) | (numSigBytes > 2 ? ((source[srcOffset + 2] << 24) >>> 24) : 0); switch (numSigBytes) { case 3: destination[destOffset] = ALPHABET[(inBuff >>> 18)]; destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f]; destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f]; destination[destOffset + 3] = ALPHABET[(inBuff) & 0x3f]; return destination; case 2: destination[destOffset] = ALPHABET[(inBuff >>> 18)]; destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f]; destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f]; destination[destOffset + 3] = EQUALS_SIGN; return destination; case 1: destination[destOffset] = ALPHABET[(inBuff >>> 18)]; destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f]; destination[destOffset + 2] = EQUALS_SIGN; destination[destOffset + 3] = EQUALS_SIGN; return destination; default: return destination; } // end switch } // end encode3to4 /** * Serializes an object and returns the Base64-encoded version of that * serialized object. If the object cannot be serialized or there is another * error, the method will return <tt>null</tt>. The object is not * GZip-compressed before being encoded. * * @param serializableObject The object to encode * @return The Base64-encoded object * @since 1.4 */ public static String encodeObject(Serializable serializableObject) { return encodeObject(serializableObject, NO_OPTIONS); } // end encodeObject /** * Serializes an object and returns the Base64-encoded version of that * serialized object. If the object cannot be serialized or there is another * error, the method will return <tt>null</tt>. * <p> * Valid options: * <ul> * <li>GZIP: gzip-compresses object before encoding it.</li> * <li>DONT_BREAK_LINES: don't break lines at 76 characters. <i>Note: * Technically, this makes your encoding non-compliant.</i></li> * </ul> * <p> * Example: <code>encodeObject( myObj, Base64.GZIP )</code> or * <p> * Example: * <code>encodeObject( myObj, Base64.GZIP | Base64.DONT_BREAK_LINES )</code> * * @param serializableObject The object to encode * @param options Specified options * @see Base64#GZIP * @see Base64#DONT_BREAK_LINES * @return The Base64-encoded object * @since 2.0 */ public static String encodeObject(Serializable serializableObject, int options) { ByteArrayOutputStream baos = new ByteArrayOutputStream(); OutputStream b64os = null; ObjectOutputStream oos = null; try { // ObjectOutputStream -> (GZIP) -> Base64 -> ByteArrayOutputStream b64os = new Base64OutputStream(baos, ENCODE | options); oos = ((options & GZIP) == GZIP) ? new ObjectOutputStream(new GZIPOutputStream(b64os)) : new ObjectOutputStream(b64os); oos.writeObject(serializableObject); return new String(baos.toByteArray(), PREFERRED_ENCODING); } catch (UnsupportedEncodingException uue) { return new String(baos.toByteArray()); } catch (IOException e) { LOG.error("error encoding object", e); return null; } finally { if (oos != null) { try { oos.close(); } catch (Exception e) { LOG.error("error closing ObjectOutputStream", e); } } if (b64os != null) { try { b64os.close(); } catch (Exception e) { LOG.error("error closing Base64OutputStream", e); } } try { baos.close(); } catch (Exception e) { LOG.error("error closing ByteArrayOutputStream", e); } } // end finally } // end encode /** * Encodes a byte array into Base64 notation. Does not GZip-compress data. * * @param source The data to convert * @return encoded byte array * @since 1.4 */ public static String encodeBytes(byte[] source) { return encodeBytes(source, 0, source.length, NO_OPTIONS); } // end encodeBytes public static String encodeBytes(String source) { return encodeBytes(source.getBytes()); } /** * Encodes a byte array into Base64 notation. * <p> * Valid options: * <ul> * <li>GZIP: gzip-compresses object before encoding it.</li> * <li>DONT_BREAK_LINES: don't break lines at 76 characters. <i>Note: * Technically, this makes your encoding non-compliant.</i></li> * </ul> * * <p> * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or * <p> * Example: * <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code> * * @param source The data to convert * @param options Specified options * @see Base64#GZIP * @see Base64#DONT_BREAK_LINES * @see Base64#URL_SAFE * @see Base64#ORDERED * @return encoded byte array * @since 2.0 */ public static String encodeBytes(byte[] source, int options) { return encodeBytes(source, 0, source.length, options); } // end encodeBytes /** * Encodes a byte array into Base64 notation. Does not GZip-compress data. * * @param source The data to convert * @param off Offset in array where conversion should begin * @param len Length of data to convert * @return encoded byte array * @since 1.4 */ public static String encodeBytes(byte[] source, int off, int len) { return encodeBytes(source, off, len, NO_OPTIONS); } // end encodeBytes /** * Encodes a byte array into Base64 notation. * <p> * Valid options: * <ul> * <li>GZIP: gzip-compresses object before encoding it.</li> * <li>DONT_BREAK_LINES: don't break lines at 76 characters. <i>Note: * Technically, this makes your encoding non-compliant.</i></li> * </ul> * * <p> * Example: <code>encodeBytes( myData, Base64.GZIP )</code> or * <p> * Example: * <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code> * * @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 * @see Base64#GZIP * @see Base64#DONT_BREAK_LINES * @see Base64#URL_SAFE * @see Base64#ORDERED * @return encoded byte array * @since 2.0 */ public static String encodeBytes(byte[] source, int off, int len, int options) { if ((options & GZIP) == GZIP) { // Compress? // GZip -> Base64 -> ByteArray ByteArrayOutputStream baos = new ByteArrayOutputStream(); GZIPOutputStream gzos = null; try { gzos = new GZIPOutputStream(new Base64OutputStream(baos, ENCODE | options)); gzos.write(source, off, len); gzos.close(); gzos = null; return new String(baos.toByteArray(), PREFERRED_ENCODING); } catch (UnsupportedEncodingException uue) { return new String(baos.toByteArray()); } catch (IOException e) { LOG.error("error encoding byte array", e); return null; } finally { if (gzos != null) { try { gzos.close(); } catch (Exception e) { LOG.error("error closing GZIPOutputStream", e); } } try { baos.close(); } catch (Exception e) { LOG.error("error closing ByteArrayOutputStream", e); } } // end finally } // end Compress // Don't compress. Better not to use streams at all then. boolean breakLines = ((options & DONT_BREAK_LINES) == 0); int len43 = len * 4 / 3; byte[] outBuff = new byte[(len43) // Main 4:3 + ((len % 3) > 0 ? 4 : 0) // padding + (breakLines ? (len43 / MAX_LINE_LENGTH) : 0)]; // New lines int d = 0; int e = 0; int len2 = len - 2; int lineLength = 0; for (; d < len2; d += 3, e += 4) { encode3to4(source, d + off, 3, outBuff, e, options); lineLength += 4; if (breakLines && lineLength == MAX_LINE_LENGTH) { outBuff[e + 4] = NEW_LINE; e++; lineLength = 0; } // end if: end of line } // end for: each piece of array if (d < len) { encode3to4(source, d + off, len - d, outBuff, e, options); e += 4; } // end if: some padding needed // Return value according to relevant encoding. try { return new String(outBuff, 0, e, PREFERRED_ENCODING); } catch (UnsupportedEncodingException uue) { return new String(outBuff, 0, e); } } // end encodeBytes /* ******** D E C O D I N G M E T H O D S ******** */ /** * Decodes four bytes from array <var>source</var> and writes the resulting * bytes (up to three of them) to <var>destination</var>. The source and * destination arrays can be manipulated anywhere along their length by * specifying <var>srcOffset</var> and <var>destOffset</var>. This method * does not check to make sure your arrays are large enough to accomodate * <var>srcOffset</var> + 4 for the <var>source</var> array or * <var>destOffset</var> + 3 for the <var>destination</var> array. This * method returns the actual number of bytes that were converted from the * Base64 encoding. * <p> * This is the lowest level of the decoding methods with all possible * parameters. * </p> * * @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 * @see Base64#URL_SAFE * @see Base64#ORDERED * @return the number of decoded bytes converted * @since 1.3 */ protected static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset, int options) { byte[] DECODABET = getDecodabet(options); if (source[srcOffset + 2] == EQUALS_SIGN) { // Example: Dk== // Two ways to do the same thing. Don't know which way I like best. // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 ) // | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 ); int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12); destination[destOffset] = (byte) (outBuff >>> 16); return 1; } else if (source[srcOffset + 3] == EQUALS_SIGN) { // Example: DkL= // Two ways to do the same thing. Don't know which way I like best. // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 ) // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 ) // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 ); int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12) | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6); destination[destOffset] = (byte) (outBuff >>> 16); destination[destOffset + 1] = (byte) (outBuff >>> 8); return 2; } else { // Example: DkLE try { // Two ways to do the same thing. Don't know which way I like best. // int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 ) // | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 ) // | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 ) // | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 ); int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18) | ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12) | ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6) | ((DECODABET[source[srcOffset + 3]] & 0xFF)); destination[destOffset] = (byte) (outBuff >> 16); destination[destOffset + 1] = (byte) (outBuff >> 8); destination[destOffset + 2] = (byte) (outBuff); return 3; } catch (Exception e) { LOG.error("error decoding bytes at " + source[srcOffset] + ": " + (DECODABET[source[srcOffset]]) + ", " + source[srcOffset + 1] + ": " + (DECODABET[source[srcOffset + 1]]) + ", " + source[srcOffset + 2] + ": " + (DECODABET[source[srcOffset + 2]]) + ", " + source[srcOffset + 3] + ": " + (DECODABET[source[srcOffset + 3]]), e); return -1; } // end catch } } // end decodeToBytes /** * Very low-level access to decoding ASCII characters in the form of a byte * array. Does not support automatically gunzipping or any other "fancy" * features. * * @param source The Base64 encoded data * @param off The offset of where to begin decoding * @param len The length of characters to decode * @param options * @see Base64#URL_SAFE * @see Base64#ORDERED * @return decoded data * @since 1.3 */ public static byte[] decode(byte[] source, int off, int len, int options) { byte[] DECODABET = getDecodabet(options); int len34 = len * 3 / 4; byte[] outBuff = new byte[len34]; // Upper limit on size of output int outBuffPosn = 0; byte[] b4 = new byte[4]; int b4Posn = 0; int i = 0; byte sbiCrop = 0; byte sbiDecode = 0; for (i = off; i < off + len; i++) { sbiCrop = (byte) (source[i] & 0x7f); // Only the low seven bits sbiDecode = DECODABET[sbiCrop]; if (sbiDecode >= WHITE_SPACE_ENC) { // Whitespace, Equals or better if (sbiDecode >= EQUALS_SIGN_ENC) { // Equals or better b4[b4Posn++] = sbiCrop; if (b4Posn > 3) { outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn, options); b4Posn = 0; // If that was the equals sign, break out of 'for' loop if (sbiCrop == EQUALS_SIGN) break; } // end if: quartet built } // end if: equals sign or better } else { LOG.error("Bad Base64 input character at " + i + ": " + source[i] + "(decimal)"); return null; } // end else: } // each input character byte[] out = new byte[outBuffPosn]; System.arraycopy(outBuff, 0, out, 0, outBuffPosn); return out; } // end decode /** * Decodes data from Base64 notation, automatically detecting gzip-compressed * data and decompressing it. * * @param s the string to decode * @return the decoded data * @since 1.4 */ public static byte[] decode(String s) { return decode(s, NO_OPTIONS); } /** * Decodes data from Base64 notation, automatically detecting gzip-compressed * data and decompressing it. * * @param s the string to decode * @param options * @see Base64#URL_SAFE * @see Base64#ORDERED * @return the decoded data * @since 1.4 */ public static byte[] decode(String s, int options) { byte[] bytes = null; try { bytes = s.getBytes(PREFERRED_ENCODING); } catch (UnsupportedEncodingException uee) { bytes = s.getBytes(); } // end catch // Decode bytes = decode(bytes, 0, bytes.length, options); // Check to see if it's gzip-compressed // GZIP Magic Two-Byte Number: 0x8b1f (35615) if (bytes != null && bytes.length >= 4) { int head = (bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00); if (GZIPInputStream.GZIP_MAGIC == head) { GZIPInputStream gzis = null; ByteArrayOutputStream baos = new ByteArrayOutputStream(); try { gzis = new GZIPInputStream(new ByteArrayInputStream(bytes)); byte[] buffer = new byte[2048]; for (int length = 0; (length = gzis.read(buffer)) >= 0;) { baos.write(buffer, 0, length); } // end while: reading input // No error? Get new bytes. bytes = baos.toByteArray(); } catch (IOException e) { // Just return originally-decoded bytes } finally { try { baos.close(); } catch (Exception e) { LOG.error("error closing ByteArrayOutputStream", e); } if (gzis != null) { try { gzis.close(); } catch (Exception e) { LOG.error("error closing GZIPInputStream", e); } } } // end finally } // end if: gzipped } // end if: bytes.length >= 2 return bytes; } // end decode /** * Attempts to decode Base64 data and deserialize a Java Object within. * Returns <tt>null</tt> if there was an error. * * @param encodedObject The Base64 data to decode * @return The decoded and deserialized object * @since 1.5 */ public static Object decodeToObject(String encodedObject) { // Decode and gunzip if necessary byte[] objBytes = decode(encodedObject); Object obj = null; ObjectInputStream ois = null; try { ois = new ObjectInputStream(new ByteArrayInputStream(objBytes)); obj = ois.readObject(); } catch (IOException e) { LOG.error("error decoding object", e); } catch (ClassNotFoundException e) { LOG.error("error decoding object", e); } finally { if (ois != null) { try { ois.close(); } catch (Exception e) { LOG.error("error closing ObjectInputStream", e); } } } // end finally return obj; } // end decodeObject /** * Convenience method for encoding data to a file. * * @param dataToEncode byte array of data to encode in base64 form * @param filename Filename for saving encoded data * @return <tt>true</tt> if successful, <tt>false</tt> otherwise * * @since 2.1 */ public static boolean encodeToFile(byte[] dataToEncode, String filename) { boolean success = false; Base64OutputStream bos = null; try { bos = new Base64OutputStream(new FileOutputStream(filename), ENCODE); bos.write(dataToEncode); success = true; } catch (IOException e) { LOG.error("error encoding file: " + filename, e); success = false; } finally { if (bos != null) { try { bos.close(); } catch (Exception e) { LOG.error("error closing Base64OutputStream", e); } } } // end finally return success; } // end encodeToFile /** * Convenience method for decoding data to a file. * * @param dataToDecode Base64-encoded data as a string * @param filename Filename for saving decoded data * @return <tt>true</tt> if successful, <tt>false</tt> otherwise * * @since 2.1 */ public static boolean decodeToFile(String dataToDecode, String filename) { boolean success = false; Base64OutputStream bos = null; try { bos = new Base64OutputStream(new FileOutputStream(filename), DECODE); bos.write(dataToDecode.getBytes(PREFERRED_ENCODING)); success = true; } catch (IOException e) { LOG.error("error decoding to file: " + filename, e); success = false; } finally { if (bos != null) { try { bos.close(); } catch (Exception e) { LOG.error("error closing Base64OutputStream", e); } } } // end finally return success; } // end decodeToFile /** * Convenience method for reading a base64-encoded file and decoding it. * * @param filename Filename for reading encoded data * @return decoded byte array or null if unsuccessful * * @since 2.1 */ public static byte[] decodeFromFile(String filename) { byte[] decodedData = null; Base64InputStream bis = null; try { File file = new File(filename); byte[] buffer = null; // Check the size of file if (file.length() > Integer.MAX_VALUE) { LOG.fatal("File is too big for this convenience method (" + file.length() + " bytes)."); return null; } // end if: file too big for int index buffer = new byte[(int) file.length()]; // Open a stream bis = new Base64InputStream(new BufferedInputStream(new FileInputStream(file)), DECODE); // Read until done int length = 0; for (int numBytes = 0; (numBytes = bis.read(buffer, length, 4096)) >= 0;) { length += numBytes; } // Save in a variable to return decodedData = new byte[length]; System.arraycopy(buffer, 0, decodedData, 0, length); } catch (IOException e) { LOG.error("Error decoding from file " + filename, e); } finally { if (bis != null) { try { bis.close(); } catch (Exception e) { LOG.error("error closing Base64InputStream", e); } } } // end finally return decodedData; } // end decodeFromFile /** * Convenience method for reading a binary file and base64-encoding it. * * @param filename Filename for reading binary data * @return base64-encoded string or null if unsuccessful * * @since 2.1 */ public static String encodeFromFile(String filename) { String encodedData = null; Base64InputStream bis = null; try { File file = new File(filename); // Need max() for math on small files (v2.2.1) byte[] buffer = new byte[Math.max((int) (file.length() * 1.4), 40)]; // Open a stream bis = new Base64InputStream(new BufferedInputStream(new FileInputStream(file)), ENCODE); // Read until done int length = 0; for (int numBytes = 0; (numBytes = bis.read(buffer, length, 4096)) >= 0;) { length += numBytes; } // Save in a variable to return encodedData = new String(buffer, 0, length, PREFERRED_ENCODING); } catch (IOException e) { LOG.error("Error encoding from file " + filename, e); } finally { if (bis != null) { try { bis.close(); } catch (Exception e) { LOG.error("error closing Base64InputStream", e); } } } // end finally return encodedData; } // end encodeFromFile /** * Reads <tt>infile</tt> and encodes it to <tt>outfile</tt>. * * @param infile Input file * @param outfile Output file * @since 2.2 */ public static void encodeFileToFile(String infile, String outfile) { String encoded = encodeFromFile(infile); OutputStream out = null; try { out = new BufferedOutputStream(new FileOutputStream(outfile)); out.write(encoded.getBytes("US-ASCII")); // Strict, 7-bit output. } catch (IOException e) { LOG.error("error encoding from file " + infile + " to " + outfile, e); } finally { if (out != null) { try { out.close(); } catch (Exception e) { LOG.error("error closing " + outfile, e); } } } // end finally } // end encodeFileToFile /** * Reads <tt>infile</tt> and decodes it to <tt>outfile</tt>. * * @param infile Input file * @param outfile Output file * @since 2.2 */ public static void decodeFileToFile(String infile, String outfile) { byte[] decoded = decodeFromFile(infile); OutputStream out = null; try { out = new BufferedOutputStream(new FileOutputStream(outfile)); out.write(decoded); } catch (IOException e) { LOG.error("error decoding from file " + infile + " to " + outfile, e); } finally { if (out != null) { try { out.close(); } catch (Exception e) { LOG.error("error closing " + outfile, e); } } } // end finally } // end decodeFileToFile /* ******** I N N E R C L A S S I N P U T S T R E A M ******** */ /** * A {@link Base64.Base64InputStream} will read data from another * <tt>InputStream</tt>, given in the constructor, and * encode/decode to/from Base64 notation on the fly. * * @see Base64 * @since 1.3 */ public static class Base64InputStream extends FilterInputStream { private boolean encode; // Encoding or decoding private int position; // Current position in the buffer private byte[] buffer; // Buffer holding converted data private int bufferLength; // Length of buffer (3 or 4) private int numSigBytes; // Meaningful bytes in the buffer private int lineLength; private boolean breakLines; // Break lines at < 80 characters private int options; // Record options private byte[] decodabet; // Local copy avoids method calls /** * Constructs a {@link Base64InputStream} in DECODE mode. * * @param in the <tt>InputStream</tt> from which to read data. * @since 1.3 */ public Base64InputStream(InputStream in) { this(in, DECODE); } // end constructor /** * Constructs a {@link Base64.Base64InputStream} in either ENCODE or DECODE mode. * <p> * Valid options: * * <pre> * ENCODE or DECODE: Encode or Decode as data is read. * DONT_BREAK_LINES: don't break lines at 76 characters * (only meaningful when encoding) * <i>Note: Technically, this makes your encoding non-compliant.</i> * </pre> * * <p> * Example: <code>new Base64.Base64InputStream( in, Base64.DECODE )</code> * * * @param in the <tt>InputStream</tt> from which to read data. * @param options Specified options * @see Base64#ENCODE * @see Base64#DECODE * @see Base64#DONT_BREAK_LINES * @since 2.0 */ public Base64InputStream(InputStream in, int options) { super(in); this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES; this.encode = (options & ENCODE) == ENCODE; this.bufferLength = encode ? 4 : 3; this.buffer = new byte[bufferLength]; this.position = -1; this.lineLength = 0; this.options = options; // Record for later, mostly to determine which // alphabet to use this.decodabet = getDecodabet(options); } // end constructor /** * Reads enough of the input stream to convert to/from Base64 and returns * the next byte. * * @return next byte * @since 1.3 */ @Override public int read() throws IOException { // Do we need to get data? if (position < 0) { if (encode) { byte[] b3 = new byte[3]; int numBinaryBytes = 0; for (int i = 0; i < 3; i++) { try { int b = in.read(); // If end of stream, b is -1. if (b >= 0) { b3[i] = (byte) b; numBinaryBytes++; } // end if: not end of stream } catch (IOException e) { // Only a problem if we got no data at all. if (i == 0) throw e; } // end catch } // end for: each needed input byte if (numBinaryBytes > 0) { encode3to4(b3, 0, numBinaryBytes, buffer, 0, options); position = 0; numSigBytes = 4; } else { return -1; } // end else } else { byte[] b4 = new byte[4]; int i = 0; for (i = 0; i < 4; i++) { // Read four "meaningful" bytes: int b = 0; do { b = in.read(); } while (b >= 0 && decodabet[b & 0x7f] <= WHITE_SPACE_ENC); if (b < 0) { break; // Reads a -1 if end of stream } b4[i] = (byte) b; } // end for: each needed input byte if (i == 4) { numSigBytes = decode4to3(b4, 0, buffer, 0, options); position = 0; } else if (i == 0) { return -1; } else { // Must have broken out from above. throw new IOException("Improperly padded Base64 input."); } // end } // end else: decode } // end else: get data // Got data? if (position >= 0) { // End of relevant data? if ( /* !encode && */position >= numSigBytes) { return -1; } if (encode && breakLines && lineLength >= MAX_LINE_LENGTH) { lineLength = 0; return '\n'; } lineLength++; // This isn't important when decoding // but throwing an extra "if" seems // just as wasteful. int b = buffer[position++]; if (position >= bufferLength) position = -1; return b & 0xFF; // This is how you "cast" a byte that's // intended to be unsigned. } // When JDK1.4 is more accepted, use an assertion here. throw new IOException("Error in Base64 code reading stream."); } // end read /** * Calls {@link #read()} repeatedly until the end of stream is reached or * <var>len</var> bytes are read. Returns number of bytes read into array * or -1 if end of stream is encountered. * * @param dest array to hold values * @param off offset for array * @param len max number of bytes to read into array * @return bytes read into array or -1 if end of stream is encountered. * @since 1.3 */ @Override public int read(byte[] dest, int off, int len) throws IOException { int i; int b; for (i = 0; i < len; i++) { b = read(); if (b >= 0) { dest[off + i] = (byte) b; } else if (i == 0) { return -1; } else { break; // Out of 'for' loop } } // end for: each byte read return i; } // end read } // end inner class InputStream /* ******** I N N E R C L A S S O U T P U T S T R E A M ******** */ /** * A {@link Base64.Base64OutputStream} will write data to another * <tt>OutputStream</tt>, given in the constructor, and * encode/decode to/from Base64 notation on the fly. * * @see Base64 * @since 1.3 */ public static class Base64OutputStream extends FilterOutputStream { private boolean encode; private int position; private byte[] buffer; private int bufferLength; private int lineLength; private boolean breakLines; private byte[] b4; // Scratch used in a few places private boolean suspendEncoding; private int options; // Record for later private byte[] decodabet; // Local copy avoids method calls /** * Constructs a {@link Base64OutputStream} in ENCODE mode. * * @param out the <tt>OutputStream</tt> to which data will be written. * @since 1.3 */ public Base64OutputStream(OutputStream out) { this(out, ENCODE); } // end constructor /** * Constructs a {@link Base64OutputStream} in either ENCODE or DECODE mode. * <p> * Valid options: * * <ul> * <li>ENCODE or DECODE: Encode or Decode as data is read.</li> * <li>DONT_BREAK_LINES: don't break lines at 76 characters (only * meaningful when encoding) <i>Note: Technically, this makes your * encoding non-compliant.</i></li> * </ul> * * <p> * Example: <code>new Base64.Base64OutputStream( out, Base64.ENCODE )</code> * * @param out the <tt>OutputStream</tt> to which data will be written. * @param options Specified options. * @see Base64#ENCODE * @see Base64#DECODE * @see Base64#DONT_BREAK_LINES * @since 1.3 */ public Base64OutputStream(OutputStream out, int options) { super(out); this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES; this.encode = (options & ENCODE) == ENCODE; this.bufferLength = encode ? 3 : 4; this.buffer = new byte[bufferLength]; this.position = 0; this.lineLength = 0; this.suspendEncoding = false; this.b4 = new byte[4]; this.options = options; this.decodabet = getDecodabet(options); } // end constructor /** * Writes the byte to the output stream after converting to/from Base64 * notation. When encoding, bytes are buffered three at a time before the * output stream actually gets a write() call. When decoding, bytes are * buffered four at a time. * * @param theByte the byte to write * @since 1.3 */ @Override public void write(int theByte) throws IOException { // Encoding suspended? if (suspendEncoding) { super.out.write(theByte); return; } // end if: supsended // Encode? if (encode) { buffer[position++] = (byte) theByte; if (position >= bufferLength) { // Enough to encode. out.write(encode3to4(b4, buffer, bufferLength, options)); lineLength += 4; if (breakLines && lineLength >= MAX_LINE_LENGTH) { out.write(NEW_LINE); lineLength = 0; } // end if: end of line position = 0; } // end if: enough to output } else { // Meaningful Base64 character? if (decodabet[theByte & 0x7f] > WHITE_SPACE_ENC) { buffer[position++] = (byte) theByte; if (position >= bufferLength) { // Enough to output. int len = decode4to3(buffer, 0, b4, 0, options); out.write(b4, 0, len); position = 0; } // end if: enough to output } else if (decodabet[theByte & 0x7f] != WHITE_SPACE_ENC) { throw new IOException("Invalid character in Base64 data."); } // end else: not white space either } // end else: decoding } // end write /** * Calls {@link #write(int)} repeatedly until <var>len</var> bytes are * written. * * @param theBytes array from which to read bytes * @param off offset for array * @param len max number of bytes to read into array * @since 1.3 */ @Override public void write(byte[] theBytes, int off, int len) throws IOException { // Encoding suspended? if (suspendEncoding) { super.out.write(theBytes, off, len); return; } // end if: supsended for (int i = 0; i < len; i++) { write(theBytes[off + i]); } // end for: each byte written } // end write /** * Method added by PHIL. [Thanks, PHIL. -Rob] This pads the buffer without * closing the stream. * * @throws IOException */ public void flushBase64() throws IOException { if (position > 0) { if (encode) { out.write(encode3to4(b4, buffer, position, options)); position = 0; } else { throw new IOException("Base64 input not properly padded."); } // end else: decoding } // end if: buffer partially full } // end flush /** * Flushes and closes (I think, in the superclass) the stream. * * @since 1.3 */ @Override public void close() throws IOException { // 1. Ensure that pending characters are written flushBase64(); // 2. Actually close the stream // Base class both flushes and closes. super.close(); buffer = null; out = null; } // end close /** * Suspends encoding of the stream. May be helpful if you need to embed a * piece of base640-encoded data in a stream. * * @throws IOException * @since 1.5.1 */ public void suspendEncoding() throws IOException { flushBase64(); this.suspendEncoding = true; } // end suspendEncoding /** * Resumes encoding of the stream. May be helpful if you need to embed a * piece of base640-encoded data in a stream. * * @since 1.5.1 */ public void resumeEncoding() { this.suspendEncoding = false; } // end resumeEncoding } // end inner class OutputStream } // end class Base64