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The source code/* * $Header: /cvsroot/mvnforum/myvietnam/src/net/myvietnam/mvncore/misc/Base64.java,v 1.7 2005/01/18 12:16:44 minhnn Exp $ * $Author: minhnn $ * $Revision: 1.7 $ * $Date: 2005/01/18 12:16:44 $ * * ==================================================================== * * Copyright (C) 2002-2005 by MyVietnam.net * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or any later version. * * All copyright notices regarding MyVietnam and MyVietnam CoreLib * MUST remain intact in the scripts and source code. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * Correspondence and Marketing Questions can be sent to: * info@MyVietnam.net * * @author: Minh Nguyen minhnn@MyVietnam.net * @author: Mai Nguyen mai.nh@MyVietnam.net */ /* * $Header: /cvsroot/mvnforum/myvietnam/src/net/myvietnam/mvncore/misc/Base64.java,v 1.7 2005/01/18 12:16:44 minhnn Exp $ * $Revision: 1.7 $ * $Date: 2005/01/18 12:16:44 $ * * ==================================================================== * * The Apache Software License, Version 1.1 * * Copyright (c) 1999 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 net.myvietnam.mvncore.misc; /** * 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 * @version $Id: Base64.java,v 1.7 2005/01/18 12:16:44 minhnn Exp $ */ public final class Base64 { static private final int BASELENGTH = 255; static private final int LOOKUPLENGTH = 64; static private final int TWENTYFOURBITGROUP = 24; static private final int EIGHTBIT = 8; static private final int SIXTEENBIT = 16; static private final int SIXBIT = 6; static private final int FOURBYTE = 4; static private final int SIGN = -128; static private final byte PAD = (byte) '='; static private byte [] base64Alphabet = new byte[BASELENGTH]; static private byte [] lookUpBase64Alphabet = new byte[LOOKUPLENGTH]; //static private final Log log = LogSource.getInstance("org.apache.commons.util.Base64"); static { for (int i = 0; i < BASELENGTH; i++ ) { base64Alphabet[i] = -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) '/'; } public static boolean isBase64( String isValidString ) { return isArrayByteBase64(isValidString.getBytes()); } public static boolean isBase64( byte octect ) { //shall we ignore white space? JEFF?? return (octect == PAD || base64Alphabet[octect] != -1); } public static boolean isArrayByteBase64( byte[] 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 ( !Base64.isBase64(arrayOctect[i]) ) return false; } return true; } /** * Encodes hex octects into Base64. * * @param binaryData Array containing binary data to encode. * @return Base64-encoded data. */ public static byte[] encode( byte[] binaryData ) { int lengthDataBits = binaryData.length*EIGHTBIT; int fewerThan24bits = lengthDataBits%TWENTYFOURBITGROUP; int numberTriplets = lengthDataBits/TWENTYFOURBITGROUP; byte encodedData[] = null; if (fewerThan24bits != 0) { //data not divisible by 24 bit encodedData = new byte[ (numberTriplets + 1 ) * 4 ]; } else { // 16 or 8 bit encodedData = new byte[ numberTriplets * 4 ]; } byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0; int encodedIndex = 0; int dataIndex = 0; int i = 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); encodedIndex = i * 4; 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 ]; } // form integral number of 6-bit groups dataIndex = i*3; encodedIndex = i*4; 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; } return encodedData; } /** * Decodes Base64 data into octects * * @param base64Data Byte array containing Base64 data * @return Array containing decoded data. */ public static byte[] decode( byte[] 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; } } |
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