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From ggreg...@apache.org
Subject cvs commit: jakarta-commons/codec/src/java/org/apache/commons/codec/binary Base64.java
Date Tue, 06 May 2003 20:52:18 GMT
ggregory    2003/05/06 13:52:18

  Modified:    codec/src/java/org/apache/commons/codec/binary Base64.java
  Log:
  Javadoc clean up such that the class description one liner forms a complete sentence. Under
1.4.x, javadoc was ending the one liner with the first initial of the last name of the first
author since a period character followed the initial.
  
  Revision  Changes    Path
  1.2       +499 -498  jakarta-commons/codec/src/java/org/apache/commons/codec/binary/Base64.java
  
  Index: Base64.java
  ===================================================================
  RCS file: /home/cvs/jakarta-commons/codec/src/java/org/apache/commons/codec/binary/Base64.java,v
  retrieving revision 1.1
  retrieving revision 1.2
  diff -u -r1.1 -r1.2
  --- Base64.java	25 Apr 2003 17:50:56 -0000	1.1
  +++ Base64.java	6 May 2003 20:52:18 -0000	1.2
  @@ -1,498 +1,499 @@
  -/*
  - * $Header$
  - * $Revision$
  - * $Date$
  -  *
  -  * ====================================================================
  -  *
  -  * The Apache Software License, Version 1.1
  -  *
  -  * Copyright (c) 2003 The Apache Software Foundation.  All rights
  -  * reserved.
  -  *
  -  * Redistribution and use in source and binary forms, with or without
  -  * modification, are permitted provided that the following conditions
  -  * are met:
  -  *
  -  * 1. Redistributions of source code must retain the above copyright
  -  *    notice, this list of conditions and the following disclaimer.
  -  *
  -  * 2. Redistributions in binary form must reproduce the above copyright
  -  *    notice, this list of conditions and the following disclaimer in
  -  *    the documentation and/or other materials provided with the
  -  *    distribution.
  -  *
  -  * 3. The end-user documentation included with the redistribution, if
  -  *    any, must include the following acknowlegement:
  -  *       "This product includes software developed by the
  -  *        Apache Software Foundation (http://www.apache.org/)."
  -  *    Alternately, this acknowlegement may appear in the software itself,
  -  *    if and wherever such third-party acknowlegements normally appear.
  -  *
  -  * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
  -  *    Foundation" must not be used to endorse or promote products derived
  -  *    from this software without prior written permission. For written
  -  *    permission, please contact apache@apache.org.
  -  *
  -  * 5. Products derived from this software may not be called "Apache"
  -  *    nor may "Apache" appear in their names without prior written
  -  *    permission of the Apache Group.
  -  *
  -  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
  -  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  -  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  -  * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
  -  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  -  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  -  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  -  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  -  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  -  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  -  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  -  * SUCH DAMAGE.
  -  * ====================================================================
  -  *
  -  * This software consists of voluntary contributions made by many
  -  * individuals on behalf of the Apache Software Foundation.  For more
  -  * information on the Apache Software Foundation, please see
  -  * <http://www.apache.org/>.
  -  *
  -  * [Additional notices, if required by prior licensing conditions]
  -  *
  -  */
  -package org.apache.commons.codec.binary;
  -
  -import org.apache.commons.codec.BinaryDecoder;
  -import org.apache.commons.codec.BinaryEncoder;
  -import org.apache.commons.codec.DecoderException;
  -import org.apache.commons.codec.EncoderException;
  -
  -/**
  -  * This class provides encode/decode for RFC 2045 Base64 as 
  -  * defined by RFC 2045, N. Freed and N. Borenstein.  <a
  -  * href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>:
  -  * Multipurpose Internet Mail Extensions (MIME) Part One: Format of
  -  * Internet Message Bodies. Reference 1996
  -  *
  -  * @author Jeffrey Rodriguez
  -  * @author <a href="dlr@apache.org">Daniel Rall</a>
  -  * @author <a href="m.redington@ucl.ac.uk">Martin Redington</a>
  -  * @since 1.0-dev
  -  *
  -  * @todo Add more documentation
  -  */
  -public class Base64 implements BinaryEncoder, BinaryDecoder {
  -
  -    // Create constants pertaining to the chunk requirement
  -    static final int CHUNK_SIZE = 76;
  -    static final byte[] CHUNK_SEPARATOR = "\n".getBytes();
  -
  -    // Create numerical and byte constants 
  -    static final int BASELENGTH = 255;
  -    static final int LOOKUPLENGTH = 64;
  -    static final int TWENTYFOURBITGROUP = 24;
  -    static final int EIGHTBIT = 8;
  -    static final int SIXTEENBIT = 16;
  -    static final int SIXBIT = 6;
  -    static final int FOURBYTE = 4;
  -    static final int SIGN = -128;
  -    static final byte PAD = (byte) '=';
  -
  -    // Create arrays to hold the base64 characters and a 
  -    // lookup for base64 chars
  -    private static byte[] base64Alphabet = new byte[BASELENGTH];
  -    private static byte[] lookUpBase64Alphabet = new byte[LOOKUPLENGTH];
  -
  -    // Populating the lookup and character arrays
  -    static {
  -        for (int i = 0; i < BASELENGTH; i++) {
  -            base64Alphabet[i] = (byte) -1;
  -        }
  -        for (int i = 'Z'; i >= 'A'; i--) {
  -            base64Alphabet[i] = (byte) (i - 'A');
  -        }
  -        for (int i = 'z'; i >= 'a'; i--) {
  -            base64Alphabet[i] = (byte) (i - 'a' + 26);
  -        }
  -        for (int i = '9'; i >= '0'; i--) {
  -            base64Alphabet[i] = (byte) (i - '0' + 52);
  -        }
  -
  -        base64Alphabet['+'] = 62;
  -        base64Alphabet['/'] = 63;
  -
  -        for (int i = 0; i <= 25; i++) {
  -            lookUpBase64Alphabet[i] = (byte) ('A' + i);
  -        }
  -
  -        for (int i = 26, j = 0; i <= 51; i++, j++) {
  -            lookUpBase64Alphabet[i] = (byte) ('a' + j);
  -        }
  -
  -        for (int i = 52, j = 0; i <= 61; i++, j++) {
  -            lookUpBase64Alphabet[i] = (byte) ('0' + j);
  -        }
  -
  -        lookUpBase64Alphabet[62] = (byte) '+';
  -        lookUpBase64Alphabet[63] = (byte) '/';
  -    }
  -
  -    private static boolean isBase64(byte octect) {
  -        if (octect == PAD) {
  -            return true;
  -        } 
  -        else if (base64Alphabet[octect] == -1) {
  -            return false;
  -        } 
  -        else {
  -            return true;
  -        }
  -    }
  -
  -    public static boolean isArrayByteBase64(byte[] arrayOctect) {
  -
  -        arrayOctect = discardWhitespace(arrayOctect);
  -
  -        int length = arrayOctect.length;
  -        if (length == 0) {
  -            // shouldn't a 0 length array be valid base64 data?
  -            // return false;
  -            return true;
  -        }
  -        for (int i = 0; i < length; i++) {
  -            if (!isBase64(arrayOctect[i])) {
  -                return false;
  -            }
  -        }
  -        return true;
  -    }
  -
  -
  -    public static byte[] encodeBase64(byte[] binaryData) {
  -        return (encodeBase64(binaryData, false));
  -    }
  -
  -    public static byte[] encodeBase64Chunked(byte[] binaryData) {
  -        return (encodeBase64(binaryData, true));
  -    }
  -
  -    public Object decode(Object pObject) throws DecoderException {
  -
  -        Object result;
  -
  -        if (!(pObject instanceof byte[])) {
  -            throw new DecoderException(
  -                "Parameter supplied to "
  -                    + "Base64 "
  -                    + "decode is not a byte[]");
  -        } 
  -        else {
  -            result = decode((byte[]) pObject);
  -        }
  -
  -        return result;
  -
  -    }
  -
  -    public byte[] decode(byte[] pArray) throws DecoderException {
  -
  -        byte[] result;
  -
  -        if (!isArrayByteBase64(pArray)) {
  -            throw new DecoderException(
  -                "Parameter supplied to "
  -                    + "Base64 "
  -                    + "decode is not a valid base64 data.");
  -        } 
  -        else {
  -            result = decodeBase64((byte[]) pArray);
  -        }
  -
  -        return (result);
  -    }
  -
  -    /**
  -     * Encodes hex octects into Base64.
  -     *
  -     * @param binaryData Array containing binary data to encode.
  -     * @return Base64-encoded data.
  -     */
  -    public static byte[] encodeBase64(byte[] binaryData, boolean isChunked) {
  -        int lengthDataBits = binaryData.length * EIGHTBIT;
  -        int fewerThan24bits = lengthDataBits % TWENTYFOURBITGROUP;
  -        int numberTriplets = lengthDataBits / TWENTYFOURBITGROUP;
  -        byte encodedData[] = null;
  -        int encodedDataLength = 0;
  -        int nbrChunks = 0;
  -
  -        if (fewerThan24bits != 0) {
  -            //data not divisible by 24 bit
  -            encodedDataLength = (numberTriplets + 1) * 4;
  -        } 
  -        else {
  -            // 16 or 8 bit
  -            encodedDataLength = numberTriplets * 4;
  -        }
  -
  -        // If the output is to be "chunked" into 76 character sections, 
  -        // for compliance with RFC 2045 MIME, then it is important to 
  -        // allow for extra length to account for the separator(s)
  -        if (isChunked) {
  -
  -            nbrChunks =
  -                (CHUNK_SEPARATOR.length == 0
  -                    ? 0
  -                    : (int) Math.ceil((float) encodedDataLength / CHUNK_SIZE));
  -            encodedDataLength += nbrChunks * CHUNK_SEPARATOR.length;
  -        }
  -
  -        encodedData = new byte[encodedDataLength];
  -
  -        byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0;
  -
  -        int encodedIndex = 0;
  -        int dataIndex = 0;
  -        int i = 0;
  -        int nextSeparatorIndex = CHUNK_SIZE;
  -        int chunksSoFar = 0;
  -
  -        //log.debug("number of triplets = " + numberTriplets);
  -        for (i = 0; i < numberTriplets; i++) {
  -            dataIndex = i * 3;
  -            b1 = binaryData[dataIndex];
  -            b2 = binaryData[dataIndex + 1];
  -            b3 = binaryData[dataIndex + 2];
  -
  -            //log.debug("b1= " + b1 +", b2= " + b2 + ", b3= " + b3);
  -
  -            l = (byte) (b2 & 0x0f);
  -            k = (byte) (b1 & 0x03);
  -
  -            byte val1 =
  -                ((b1 & SIGN) == 0)
  -                    ? (byte) (b1 >> 2)
  -                    : (byte) ((b1) >> 2 ^ 0xc0);
  -            byte val2 =
  -                ((b2 & SIGN) == 0)
  -                    ? (byte) (b2 >> 4)
  -                    : (byte) ((b2) >> 4 ^ 0xf0);
  -            byte val3 =
  -                ((b3 & SIGN) == 0)
  -                    ? (byte) (b3 >> 6)
  -                    : (byte) ((b3) >> 6 ^ 0xfc);
  -
  -            encodedData[encodedIndex] = lookUpBase64Alphabet[val1];
  -            //log.debug( "val2 = " + val2 );
  -            //log.debug( "k4   = " + (k<<4) );
  -            //log.debug(  "vak  = " + (val2 | (k<<4)) );
  -            encodedData[encodedIndex + 1] =
  -                lookUpBase64Alphabet[val2 | (k << 4)];
  -            encodedData[encodedIndex + 2] =
  -                lookUpBase64Alphabet[(l << 2) | val3];
  -            encodedData[encodedIndex + 3] = lookUpBase64Alphabet[b3 & 0x3f];
  -
  -            encodedIndex += 4;
  -
  -            // If we are chunking, let's put a chunk separator down.
  -            if (isChunked) {
  -                // this assumes that CHUNK_SIZE % 4 == 0
  -                if (encodedIndex == nextSeparatorIndex) {
  -                    System.arraycopy(
  -                        CHUNK_SEPARATOR,
  -                        0,
  -                        encodedData,
  -                        encodedIndex,
  -                        CHUNK_SEPARATOR.length);
  -                    chunksSoFar++;
  -                    nextSeparatorIndex =
  -                        (CHUNK_SIZE * (chunksSoFar + 1))
  -                            + (chunksSoFar * CHUNK_SEPARATOR.length);
  -                    encodedIndex += CHUNK_SEPARATOR.length;
  -                }
  -            }
  -        }
  -
  -        // form integral number of 6-bit groups
  -        dataIndex = i * 3;
  -
  -        if (fewerThan24bits == EIGHTBIT) {
  -            b1 = binaryData[dataIndex];
  -            k = (byte) (b1 & 0x03);
  -            //log.debug("b1=" + b1);
  -            //log.debug("b1<<2 = " + (b1>>2) );
  -            byte val1 =
  -                ((b1 & SIGN) == 0)
  -                    ? (byte) (b1 >> 2)
  -                    : (byte) ((b1) >> 2 ^ 0xc0);
  -            encodedData[encodedIndex] = lookUpBase64Alphabet[val1];
  -            encodedData[encodedIndex + 1] = lookUpBase64Alphabet[k << 4];
  -            encodedData[encodedIndex + 2] = PAD;
  -            encodedData[encodedIndex + 3] = PAD;
  -        } 
  -        else if (fewerThan24bits == SIXTEENBIT) {
  -
  -            b1 = binaryData[dataIndex];
  -            b2 = binaryData[dataIndex + 1];
  -            l = (byte) (b2 & 0x0f);
  -            k = (byte) (b1 & 0x03);
  -
  -            byte val1 =
  -                ((b1 & SIGN) == 0)
  -                    ? (byte) (b1 >> 2)
  -                    : (byte) ((b1) >> 2 ^ 0xc0);
  -            byte val2 =
  -                ((b2 & SIGN) == 0)
  -                    ? (byte) (b2 >> 4)
  -                    : (byte) ((b2) >> 4 ^ 0xf0);
  -
  -            encodedData[encodedIndex] = lookUpBase64Alphabet[val1];
  -            encodedData[encodedIndex + 1] =
  -                lookUpBase64Alphabet[val2 | (k << 4)];
  -            encodedData[encodedIndex + 2] = lookUpBase64Alphabet[l << 2];
  -            encodedData[encodedIndex + 3] = PAD;
  -        }
  -
  -        if (isChunked) {
  -            // we also add a separator to the end of the final chunk.
  -            if (chunksSoFar < nbrChunks) {
  -                System.arraycopy(
  -                    CHUNK_SEPARATOR,
  -                    0,
  -                    encodedData,
  -                    encodedDataLength - CHUNK_SEPARATOR.length,
  -                    CHUNK_SEPARATOR.length);
  -            }
  -        }
  -
  -        return encodedData;
  -    }
  -
  -    /**
  -     * Decodes Base64 data into octects
  -     *
  -     * @param binaryData Byte array containing Base64 data
  -     * @return Array containing decoded data.
  -     */
  -    public static byte[] decodeBase64(byte[] base64Data) {
  -        // RFC 2045 suggests line wrapping at (no more than) 76
  -        // characters -- we may have embedded whitespace.
  -        base64Data = discardWhitespace(base64Data);
  -
  -        // handle the edge case, so we don't have to worry about it later
  -        if (base64Data.length == 0) {
  -            return new byte[0];
  -        }
  -
  -        int numberQuadruple = base64Data.length / FOURBYTE;
  -        byte decodedData[] = null;
  -        byte b1 = 0, b2 = 0, b3 = 0, b4 = 0, marker0 = 0, marker1 = 0;
  -
  -        // Throw away anything not in base64Data
  -
  -        int encodedIndex = 0;
  -        int dataIndex = 0;
  -        {
  -            // this sizes the output array properly - rlw
  -            int lastData = base64Data.length;
  -            // ignore the '=' padding
  -            while (base64Data[lastData - 1] == PAD) {
  -                if (--lastData == 0) {
  -                    return new byte[0];
  -                }
  -            }
  -            decodedData = new byte[lastData - numberQuadruple];
  -        }
  -
  -        for (int i = 0; i < numberQuadruple; i++) {
  -            dataIndex = i * 4;
  -            marker0 = base64Data[dataIndex + 2];
  -            marker1 = base64Data[dataIndex + 3];
  -
  -            b1 = base64Alphabet[base64Data[dataIndex]];
  -            b2 = base64Alphabet[base64Data[dataIndex + 1]];
  -
  -            if (marker0 != PAD && marker1 != PAD) {
  -                //No PAD e.g 3cQl
  -                b3 = base64Alphabet[marker0];
  -                b4 = base64Alphabet[marker1];
  -
  -                decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
  -                decodedData[encodedIndex + 1] =
  -                    (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
  -                decodedData[encodedIndex + 2] = (byte) (b3 << 6 | b4);
  -            } 
  -            else if (marker0 == PAD) {
  -                //Two PAD e.g. 3c[Pad][Pad]
  -                decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
  -            } 
  -            else if (marker1 == PAD) {
  -                //One PAD e.g. 3cQ[Pad]
  -                b3 = base64Alphabet[marker0];
  -
  -                decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
  -                decodedData[encodedIndex + 1] =
  -                    (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
  -            }
  -            encodedIndex += 3;
  -        }
  -        return decodedData;
  -    }
  -
  -    /**
  -     * Discards any whitespace from a base-64 encoded block.
  -     *
  -     * @param data The base-64 encoded data to discard the whitespace
  -     * from.
  -     * @return The data, less whitespace (see RFC 2045).
  -     */
  -    static byte[] discardWhitespace(byte[] data) {
  -        byte groomedData[] = new byte[data.length];
  -        int bytesCopied = 0;
  -
  -        for (int i = 0; i < data.length; i++) {
  -            switch (data[i]) {
  -                case (byte) ' ' :
  -                case (byte) '\n' :
  -                case (byte) '\r' :
  -                case (byte) '\t' :
  -                    break;
  -                default:
  -                    groomedData[bytesCopied++] = data[i];
  -            }
  -        }
  -
  -        byte packedData[] = new byte[bytesCopied];
  -
  -        System.arraycopy(groomedData, 0, packedData, 0, bytesCopied);
  -
  -        return packedData;
  -    }
  -
  -    // Implementation of the Encoder Interface
  -
  -    /**
  -     * encode an Object
  -     */
  -    public Object encode(Object pObject) throws EncoderException {
  -
  -        Object result;
  -
  -        if (!(pObject instanceof byte[])) {
  -            throw new EncoderException(
  -                "Parameter supplied to "
  -                    + "Base64 "
  -                    + "encode is not a byte[]");
  -        } 
  -        else {
  -            result = encode((byte[]) pObject);
  -        }
  -
  -        return result;
  -
  -    }
  -
  -    public byte[] encode(byte[] pArray) throws EncoderException {
  -        return (encodeBase64(pArray, false));
  -    }
  -
  -}
  +/*
  + * $Header$
  + * $Revision$
  + * $Date$
  +  *
  +  * ====================================================================
  +  *
  +  * The Apache Software License, Version 1.1
  +  *
  +  * Copyright (c) 2003 The Apache Software Foundation.  All rights
  +  * reserved.
  +  *
  +  * Redistribution and use in source and binary forms, with or without
  +  * modification, are permitted provided that the following conditions
  +  * are met:
  +  *
  +  * 1. Redistributions of source code must retain the above copyright
  +  *    notice, this list of conditions and the following disclaimer.
  +  *
  +  * 2. Redistributions in binary form must reproduce the above copyright
  +  *    notice, this list of conditions and the following disclaimer in
  +  *    the documentation and/or other materials provided with the
  +  *    distribution.
  +  *
  +  * 3. The end-user documentation included with the redistribution, if
  +  *    any, must include the following acknowlegement:
  +  *       "This product includes software developed by the
  +  *        Apache Software Foundation (http://www.apache.org/)."
  +  *    Alternately, this acknowlegement may appear in the software itself,
  +  *    if and wherever such third-party acknowlegements normally appear.
  +  *
  +  * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
  +  *    Foundation" must not be used to endorse or promote products derived
  +  *    from this software without prior written permission. For written
  +  *    permission, please contact apache@apache.org.
  +  *
  +  * 5. Products derived from this software may not be called "Apache"
  +  *    nor may "Apache" appear in their names without prior written
  +  *    permission of the Apache Group.
  +  *
  +  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
  +  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  +  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  +  * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
  +  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  +  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  +  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  +  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  +  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  +  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  +  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  +  * SUCH DAMAGE.
  +  * ====================================================================
  +  *
  +  * This software consists of voluntary contributions made by many
  +  * individuals on behalf of the Apache Software Foundation.  For more
  +  * information on the Apache Software Foundation, please see
  +  * <http://www.apache.org/>.
  +  *
  +  * [Additional notices, if required by prior licensing conditions]
  +  *
  +  */
  +package org.apache.commons.codec.binary;
  +
  +import org.apache.commons.codec.BinaryDecoder;
  +import org.apache.commons.codec.BinaryEncoder;
  +import org.apache.commons.codec.DecoderException;
  +import org.apache.commons.codec.EncoderException;
  +
  +/**
  +  * Provides encode/decode for RFC 2045 Base64 as 
  +  * defined by RFC 2045, by Freed and Borenstein.  <a
  +  * href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045</a>:
  +  * Multipurpose Internet Mail Extensions (MIME) Part One: Format of
  +  * Internet Message Bodies. Reference 1996.
  +  *
  +  * @author Jeffrey Rodriguez
  +  * @author <a href="dlr@apache.org">Daniel Rall</a>
  +  * @author <a href="m.redington@ucl.ac.uk">Martin Redington</a>
  +  * @author <a href="mailto:ggregory@seagullsw.com">Gary Gregory</a>
  +  * @since 1.0-dev
  +  *
  +  * @todo Add more documentation
  +  */
  +public class Base64 implements BinaryEncoder, BinaryDecoder {
  +
  +    // Create constants pertaining to the chunk requirement
  +    static final int CHUNK_SIZE = 76;
  +    static final byte[] CHUNK_SEPARATOR = "\n".getBytes();
  +
  +    // Create numerical and byte constants 
  +    static final int BASELENGTH = 255;
  +    static final int LOOKUPLENGTH = 64;
  +    static final int TWENTYFOURBITGROUP = 24;
  +    static final int EIGHTBIT = 8;
  +    static final int SIXTEENBIT = 16;
  +    static final int SIXBIT = 6;
  +    static final int FOURBYTE = 4;
  +    static final int SIGN = -128;
  +    static final byte PAD = (byte) '=';
  +
  +    // Create arrays to hold the base64 characters and a 
  +    // lookup for base64 chars
  +    private static byte[] base64Alphabet = new byte[BASELENGTH];
  +    private static byte[] lookUpBase64Alphabet = new byte[LOOKUPLENGTH];
  +
  +    // Populating the lookup and character arrays
  +    static {
  +        for (int i = 0; i < BASELENGTH; i++) {
  +            base64Alphabet[i] = (byte) -1;
  +        }
  +        for (int i = 'Z'; i >= 'A'; i--) {
  +            base64Alphabet[i] = (byte) (i - 'A');
  +        }
  +        for (int i = 'z'; i >= 'a'; i--) {
  +            base64Alphabet[i] = (byte) (i - 'a' + 26);
  +        }
  +        for (int i = '9'; i >= '0'; i--) {
  +            base64Alphabet[i] = (byte) (i - '0' + 52);
  +        }
  +
  +        base64Alphabet['+'] = 62;
  +        base64Alphabet['/'] = 63;
  +
  +        for (int i = 0; i <= 25; i++) {
  +            lookUpBase64Alphabet[i] = (byte) ('A' + i);
  +        }
  +
  +        for (int i = 26, j = 0; i <= 51; i++, j++) {
  +            lookUpBase64Alphabet[i] = (byte) ('a' + j);
  +        }
  +
  +        for (int i = 52, j = 0; i <= 61; i++, j++) {
  +            lookUpBase64Alphabet[i] = (byte) ('0' + j);
  +        }
  +
  +        lookUpBase64Alphabet[62] = (byte) '+';
  +        lookUpBase64Alphabet[63] = (byte) '/';
  +    }
  +
  +    private static boolean isBase64(byte octect) {
  +        if (octect == PAD) {
  +            return true;
  +        } 
  +        else if (base64Alphabet[octect] == -1) {
  +            return false;
  +        } 
  +        else {
  +            return true;
  +        }
  +    }
  +
  +    public static boolean isArrayByteBase64(byte[] arrayOctect) {
  +
  +        arrayOctect = discardWhitespace(arrayOctect);
  +
  +        int length = arrayOctect.length;
  +        if (length == 0) {
  +            // shouldn't a 0 length array be valid base64 data?
  +            // return false;
  +            return true;
  +        }
  +        for (int i = 0; i < length; i++) {
  +            if (!isBase64(arrayOctect[i])) {
  +                return false;
  +            }
  +        }
  +        return true;
  +    }
  +
  +
  +    public static byte[] encodeBase64(byte[] binaryData) {
  +        return (encodeBase64(binaryData, false));
  +    }
  +
  +    public static byte[] encodeBase64Chunked(byte[] binaryData) {
  +        return (encodeBase64(binaryData, true));
  +    }
  +
  +    public Object decode(Object pObject) throws DecoderException {
  +
  +        Object result;
  +
  +        if (!(pObject instanceof byte[])) {
  +            throw new DecoderException(
  +                "Parameter supplied to "
  +                    + "Base64 "
  +                    + "decode is not a byte[]");
  +        } 
  +        else {
  +            result = decode((byte[]) pObject);
  +        }
  +
  +        return result;
  +
  +    }
  +
  +    public byte[] decode(byte[] pArray) throws DecoderException {
  +
  +        byte[] result;
  +
  +        if (!isArrayByteBase64(pArray)) {
  +            throw new DecoderException(
  +                "Parameter supplied to "
  +                    + "Base64 "
  +                    + "decode is not a valid base64 data.");
  +        } 
  +        else {
  +            result = decodeBase64((byte[]) pArray);
  +        }
  +
  +        return (result);
  +    }
  +
  +    /**
  +     * Encodes hex octects into Base64.
  +     *
  +     * @param binaryData Array containing binary data to encode.
  +     * @return Base64-encoded data.
  +     */
  +    public static byte[] encodeBase64(byte[] binaryData, boolean isChunked) {
  +        int lengthDataBits = binaryData.length * EIGHTBIT;
  +        int fewerThan24bits = lengthDataBits % TWENTYFOURBITGROUP;
  +        int numberTriplets = lengthDataBits / TWENTYFOURBITGROUP;
  +        byte encodedData[] = null;
  +        int encodedDataLength = 0;
  +        int nbrChunks = 0;
  +
  +        if (fewerThan24bits != 0) {
  +            //data not divisible by 24 bit
  +            encodedDataLength = (numberTriplets + 1) * 4;
  +        } 
  +        else {
  +            // 16 or 8 bit
  +            encodedDataLength = numberTriplets * 4;
  +        }
  +
  +        // If the output is to be "chunked" into 76 character sections, 
  +        // for compliance with RFC 2045 MIME, then it is important to 
  +        // allow for extra length to account for the separator(s)
  +        if (isChunked) {
  +
  +            nbrChunks =
  +                (CHUNK_SEPARATOR.length == 0
  +                    ? 0
  +                    : (int) Math.ceil((float) encodedDataLength / CHUNK_SIZE));
  +            encodedDataLength += nbrChunks * CHUNK_SEPARATOR.length;
  +        }
  +
  +        encodedData = new byte[encodedDataLength];
  +
  +        byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0;
  +
  +        int encodedIndex = 0;
  +        int dataIndex = 0;
  +        int i = 0;
  +        int nextSeparatorIndex = CHUNK_SIZE;
  +        int chunksSoFar = 0;
  +
  +        //log.debug("number of triplets = " + numberTriplets);
  +        for (i = 0; i < numberTriplets; i++) {
  +            dataIndex = i * 3;
  +            b1 = binaryData[dataIndex];
  +            b2 = binaryData[dataIndex + 1];
  +            b3 = binaryData[dataIndex + 2];
  +
  +            //log.debug("b1= " + b1 +", b2= " + b2 + ", b3= " + b3);
  +
  +            l = (byte) (b2 & 0x0f);
  +            k = (byte) (b1 & 0x03);
  +
  +            byte val1 =
  +                ((b1 & SIGN) == 0)
  +                    ? (byte) (b1 >> 2)
  +                    : (byte) ((b1) >> 2 ^ 0xc0);
  +            byte val2 =
  +                ((b2 & SIGN) == 0)
  +                    ? (byte) (b2 >> 4)
  +                    : (byte) ((b2) >> 4 ^ 0xf0);
  +            byte val3 =
  +                ((b3 & SIGN) == 0)
  +                    ? (byte) (b3 >> 6)
  +                    : (byte) ((b3) >> 6 ^ 0xfc);
  +
  +            encodedData[encodedIndex] = lookUpBase64Alphabet[val1];
  +            //log.debug( "val2 = " + val2 );
  +            //log.debug( "k4   = " + (k<<4) );
  +            //log.debug(  "vak  = " + (val2 | (k<<4)) );
  +            encodedData[encodedIndex + 1] =
  +                lookUpBase64Alphabet[val2 | (k << 4)];
  +            encodedData[encodedIndex + 2] =
  +                lookUpBase64Alphabet[(l << 2) | val3];
  +            encodedData[encodedIndex + 3] = lookUpBase64Alphabet[b3 & 0x3f];
  +
  +            encodedIndex += 4;
  +
  +            // If we are chunking, let's put a chunk separator down.
  +            if (isChunked) {
  +                // this assumes that CHUNK_SIZE % 4 == 0
  +                if (encodedIndex == nextSeparatorIndex) {
  +                    System.arraycopy(
  +                        CHUNK_SEPARATOR,
  +                        0,
  +                        encodedData,
  +                        encodedIndex,
  +                        CHUNK_SEPARATOR.length);
  +                    chunksSoFar++;
  +                    nextSeparatorIndex =
  +                        (CHUNK_SIZE * (chunksSoFar + 1))
  +                            + (chunksSoFar * CHUNK_SEPARATOR.length);
  +                    encodedIndex += CHUNK_SEPARATOR.length;
  +                }
  +            }
  +        }
  +
  +        // form integral number of 6-bit groups
  +        dataIndex = i * 3;
  +
  +        if (fewerThan24bits == EIGHTBIT) {
  +            b1 = binaryData[dataIndex];
  +            k = (byte) (b1 & 0x03);
  +            //log.debug("b1=" + b1);
  +            //log.debug("b1<<2 = " + (b1>>2) );
  +            byte val1 =
  +                ((b1 & SIGN) == 0)
  +                    ? (byte) (b1 >> 2)
  +                    : (byte) ((b1) >> 2 ^ 0xc0);
  +            encodedData[encodedIndex] = lookUpBase64Alphabet[val1];
  +            encodedData[encodedIndex + 1] = lookUpBase64Alphabet[k << 4];
  +            encodedData[encodedIndex + 2] = PAD;
  +            encodedData[encodedIndex + 3] = PAD;
  +        } 
  +        else if (fewerThan24bits == SIXTEENBIT) {
  +
  +            b1 = binaryData[dataIndex];
  +            b2 = binaryData[dataIndex + 1];
  +            l = (byte) (b2 & 0x0f);
  +            k = (byte) (b1 & 0x03);
  +
  +            byte val1 =
  +                ((b1 & SIGN) == 0)
  +                    ? (byte) (b1 >> 2)
  +                    : (byte) ((b1) >> 2 ^ 0xc0);
  +            byte val2 =
  +                ((b2 & SIGN) == 0)
  +                    ? (byte) (b2 >> 4)
  +                    : (byte) ((b2) >> 4 ^ 0xf0);
  +
  +            encodedData[encodedIndex] = lookUpBase64Alphabet[val1];
  +            encodedData[encodedIndex + 1] =
  +                lookUpBase64Alphabet[val2 | (k << 4)];
  +            encodedData[encodedIndex + 2] = lookUpBase64Alphabet[l << 2];
  +            encodedData[encodedIndex + 3] = PAD;
  +        }
  +
  +        if (isChunked) {
  +            // we also add a separator to the end of the final chunk.
  +            if (chunksSoFar < nbrChunks) {
  +                System.arraycopy(
  +                    CHUNK_SEPARATOR,
  +                    0,
  +                    encodedData,
  +                    encodedDataLength - CHUNK_SEPARATOR.length,
  +                    CHUNK_SEPARATOR.length);
  +            }
  +        }
  +
  +        return encodedData;
  +    }
  +
  +    /**
  +     * Decodes Base64 data into octects
  +     *
  +     * @param binaryData Byte array containing Base64 data
  +     * @return Array containing decoded data.
  +     */
  +    public static byte[] decodeBase64(byte[] base64Data) {
  +        // RFC 2045 suggests line wrapping at (no more than) 76
  +        // characters -- we may have embedded whitespace.
  +        base64Data = discardWhitespace(base64Data);
  +
  +        // handle the edge case, so we don't have to worry about it later
  +        if (base64Data.length == 0) {
  +            return new byte[0];
  +        }
  +
  +        int numberQuadruple = base64Data.length / FOURBYTE;
  +        byte decodedData[] = null;
  +        byte b1 = 0, b2 = 0, b3 = 0, b4 = 0, marker0 = 0, marker1 = 0;
  +
  +        // Throw away anything not in base64Data
  +
  +        int encodedIndex = 0;
  +        int dataIndex = 0;
  +        {
  +            // this sizes the output array properly - rlw
  +            int lastData = base64Data.length;
  +            // ignore the '=' padding
  +            while (base64Data[lastData - 1] == PAD) {
  +                if (--lastData == 0) {
  +                    return new byte[0];
  +                }
  +            }
  +            decodedData = new byte[lastData - numberQuadruple];
  +        }
  +
  +        for (int i = 0; i < numberQuadruple; i++) {
  +            dataIndex = i * 4;
  +            marker0 = base64Data[dataIndex + 2];
  +            marker1 = base64Data[dataIndex + 3];
  +
  +            b1 = base64Alphabet[base64Data[dataIndex]];
  +            b2 = base64Alphabet[base64Data[dataIndex + 1]];
  +
  +            if (marker0 != PAD && marker1 != PAD) {
  +                //No PAD e.g 3cQl
  +                b3 = base64Alphabet[marker0];
  +                b4 = base64Alphabet[marker1];
  +
  +                decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
  +                decodedData[encodedIndex + 1] =
  +                    (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
  +                decodedData[encodedIndex + 2] = (byte) (b3 << 6 | b4);
  +            } 
  +            else if (marker0 == PAD) {
  +                //Two PAD e.g. 3c[Pad][Pad]
  +                decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
  +            } 
  +            else if (marker1 == PAD) {
  +                //One PAD e.g. 3cQ[Pad]
  +                b3 = base64Alphabet[marker0];
  +
  +                decodedData[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
  +                decodedData[encodedIndex + 1] =
  +                    (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
  +            }
  +            encodedIndex += 3;
  +        }
  +        return decodedData;
  +    }
  +
  +    /**
  +     * Discards any whitespace from a base-64 encoded block.
  +     *
  +     * @param data The base-64 encoded data to discard the whitespace
  +     * from.
  +     * @return The data, less whitespace (see RFC 2045).
  +     */
  +    static byte[] discardWhitespace(byte[] data) {
  +        byte groomedData[] = new byte[data.length];
  +        int bytesCopied = 0;
  +
  +        for (int i = 0; i < data.length; i++) {
  +            switch (data[i]) {
  +                case (byte) ' ' :
  +                case (byte) '\n' :
  +                case (byte) '\r' :
  +                case (byte) '\t' :
  +                    break;
  +                default:
  +                    groomedData[bytesCopied++] = data[i];
  +            }
  +        }
  +
  +        byte packedData[] = new byte[bytesCopied];
  +
  +        System.arraycopy(groomedData, 0, packedData, 0, bytesCopied);
  +
  +        return packedData;
  +    }
  +
  +    // Implementation of the Encoder Interface
  +
  +    /**
  +     * encode an Object
  +     */
  +    public Object encode(Object pObject) throws EncoderException {
  +
  +        Object result;
  +
  +        if (!(pObject instanceof byte[])) {
  +            throw new EncoderException(
  +                "Parameter supplied to "
  +                    + "Base64 "
  +                    + "encode is not a byte[]");
  +        } 
  +        else {
  +            result = encode((byte[]) pObject);
  +        }
  +
  +        return result;
  +
  +    }
  +
  +    public byte[] encode(byte[] pArray) throws EncoderException {
  +        return (encodeBase64(pArray, false));
  +    }
  +
  +}
  
  
  

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