    001    /* ========================================================================
    002     * JCommon : a free general purpose class library for the Java(tm) platform
    003     * ========================================================================
    004     *
    005     * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
    006     *
    007     * Project Info:  http://www.jfree.org/jcommon/index.html
    008     *
    009     * This library is free software; you can redistribute it and/or modify it
    010     * under the terms of the GNU Lesser General Public License as published by
    011     * the Free Software Foundation; either version 2.1 of the License, or
    012     * (at your option) any later version.
    013     *
    014     * This library is distributed in the hope that it will be useful, but
    015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
    016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
    017     * License for more details.
    018     *
    019     * You should have received a copy of the GNU Lesser General Public
    020     * License along with this library; if not, write to the Free Software
    021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
    022     * USA.
    023     *
    024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
    025     * in the United States and other countries.]
    026     *
    027     * -------------------------------------
    028     * AbstractElementDefinitionHandler.java
    029     * -------------------------------------
    030     * (C)opyright 2003-2005, by Thomas Morgner and Contributors.
    031     *
    032     * Original Author:  Kevin Kelley <kelley@ruralnet.net> -
    033     *                   30718 Rd. 28, La Junta, CO, 81050  USA.
    034     *
    035     * $Id: Base64.java,v 1.4 2005/10/18 13:33:53 mungady Exp $
    036     *
    037     * Changes
    038     * -------------------------
    039     * 23.09.2003 : Initial version
    040     *
    041     */
    042    package org.jfree.xml.util;
    043
    044    import java.io.BufferedInputStream;
    045    import java.io.BufferedOutputStream;
    046    import java.io.BufferedReader;
    047    import java.io.BufferedWriter;
    048    import java.io.ByteArrayOutputStream;
    049    import java.io.CharArrayWriter;
    050    import java.io.File;
    051    import java.io.FileInputStream;
    052    import java.io.FileOutputStream;
    053    import java.io.FileReader;
    054    import java.io.FileWriter;
    055    import java.io.InputStream;
    056    import java.io.OutputStream;
    057    import java.io.Reader;
    058    import java.io.Writer;
    059
    060    /**
    061     * Provides encoding of raw bytes to base64-encoded characters, and
    062     * decoding of base64 characters to raw bytes.
    063     * date: 06 August 1998
    064     * modified: 14 February 2000
    065     * modified: 22 September 2000
    066     *
    067     * @author Kevin Kelley (kelley@ruralnet.net)
    068     * @version 1.3
    069     */
    070    public class Base64 {
    071
    072      private Base64 ()
    073      {
    074      }
    075
    076        /**
    077         * returns an array of base64-encoded characters to represent the
    078         * passed data array.
    079         *
    080         * @param data the array of bytes to encode
    081         * @return base64-coded character array.
    082         */
    083        public static char[] encode(final byte[] data) {
    084            final char[] out = new char[((data.length + 2) / 3) * 4];
    085
    086            //
    087            // 3 bytes encode to 4 chars.  Output is always an even
    088            // multiple of 4 characters.
    089            //
    090            for (int i = 0, index = 0; i < data.length; i += 3, index += 4) {
    091                boolean quad = false;
    092                boolean trip = false;
    093
    094                int val = (0xFF & data[i]);
    095                val <<= 8;
    096                if ((i + 1) < data.length) {
    097                    val |= (0xFF & data[i + 1]);
    098                    trip = true;
    099                }
    100                val <<= 8;
    101                if ((i + 2) < data.length) {
    102                    val |= (0xFF & data[i + 2]);
    103                    quad = true;
    104                }
    105                out[index + 3] = alphabet[(quad ? (val & 0x3F) : 64)];
    106                val >>= 6;
    107                out[index + 2] = alphabet[(trip ? (val & 0x3F) : 64)];
    108                val >>= 6;
    109                out[index + 1] = alphabet[val & 0x3F];
    110                val >>= 6;
    111                out[index + 0] = alphabet[val & 0x3F];
    112            }
    113            return out;
    114        }
    115
    116        /**
    117         * Decodes a BASE-64 encoded stream to recover the original
    118         * data. White space before and after will be trimmed away,
    119         * but no other manipulation of the input will be performed.
    120         *
    121         * As of version 1.2 this method will properly handle input
    122         * containing junk characters (newlines and the like) rather
    123         * than throwing an error. It does this by pre-parsing the
    124         * input and generating from that a count of VALID input
    125         * characters.
    126         *
    127         * @param data  the character data.
    128         *
    129         * @return The decoded data.
    130         */
    131        public static byte[] decode(final char[] data) {
    132            // as our input could contain non-BASE64 data (newlines,
    133            // whitespace of any sort, whatever) we must first adjust
    134            // our count of USABLE data so that...
    135            // (a) we don't misallocate the output array, and
    136            // (b) think that we miscalculated our data length
    137            //     just because of extraneous throw-away junk
    138
    139            int tempLen = data.length;
    140            for (int ix = 0; ix < data.length; ix++) {
    141                if ((data[ix] > 255) || codes[data[ix]] < 0) {
    142                    --tempLen; // ignore non-valid chars and padding
    143                }
    144            }
    145            // calculate required length:
    146            //  -- 3 bytes for every 4 valid base64 chars
    147            //  -- plus 2 bytes if there are 3 extra base64 chars,
    148            //     or plus 1 byte if there are 2 extra.
    149
    150            int len = (tempLen / 4) * 3;
    151            if ((tempLen % 4) == 3) {
    152                len += 2;
    153            }
    154            if ((tempLen % 4) == 2) {
    155                len += 1;
    156            }
    157
    158            final byte[] out = new byte[len];
    159
    160
    161            int shift = 0; // # of excess bits stored in accum
    162            int accum = 0; // excess bits
    163            int index = 0;
    164
    165            // we now go through the entire array (NOT using the 'tempLen' value)
    166            for (int ix = 0; ix < data.length; ix++) {
    167                final int value = (data[ix] > 255) ? -1 : codes[data[ix]];
    168
    169                if (value >= 0) { // skip over non-code
    170                    accum <<= 6; // bits shift up by 6 each time thru
    171                    shift += 6; // loop, with new bits being put in
    172                    accum |= value; // at the bottom.
    173                    if (shift >= 8) { // whenever there are 8 or more shifted in,
    174                        shift -= 8; // write them out (from the top, leaving any
    175                        out[index++] = // excess at the bottom for next iteration.
    176                            (byte) ((accum >> shift) & 0xff);
    177                    }
    178                }
    179                // we will also have skipped processing a padding null byte ('=') here;
    180                // these are used ONLY for padding to an even length and do not legally
    181                // occur as encoded data. for this reason we can ignore the fact that
    182                // no index++ operation occurs in that special case: the out[] array is
    183                // initialized to all-zero bytes to start with and that works to our
    184                // advantage in this combination.
    185            }
    186
    187            // if there is STILL something wrong we just have to throw up now!
    188            if (index != out.length) {
    189                throw new Error("Miscalculated data length (wrote "
    190                    + index + " instead of " + out.length + ")");
    191            }
    192
    193            return out;
    194        }
    195
    196
    197        //
    198        // code characters for values 0..63
    199        //
    200        private static char[] alphabet =
    201            "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=".toCharArray();
    202
    203        //
    204        // lookup table for converting base64 characters to value in range 0..63
    205        //
    206        private static byte[] codes = new byte[256];
    207
    208        static {
    209            for (int i = 0; i < 256; i++) {
    210                codes[i] = -1;
    211            }
    212            for (int i = 'A'; i <= 'Z'; i++) {
    213                codes[i] = (byte) (i - 'A');
    214            }
    215            for (int i = 'a'; i <= 'z'; i++) {
    216                codes[i] = (byte) (26 + i - 'a');
    217            }
    218            for (int i = '0'; i <= '9'; i++) {
    219                codes[i] = (byte) (52 + i - '0');
    220            }
    221            codes['+'] = 62;
    222            codes['/'] = 63;
    223        }
    224
    225
    226
    227
    228        ///////////////////////////////////////////////////
    229        // remainder (main method and helper functions) is
    230        // for testing purposes only, feel free to clip it.
    231        ///////////////////////////////////////////////////
    232
    233        /**
    234         * Entry point.
    235         *
    236         * @param args  the command line arguments.
    237         */
    238        public static void main(final String[] args) {
    239            boolean decode = false;
    240
    241            if (args.length == 0) {
    242                System.out.println("usage:  java Base64 [-d[ecode]] filename");
    243                System.exit(0);
    244            }
    245            for (int i = 0; i < args.length; i++) {
    246                if ("-decode".equalsIgnoreCase(args[i])) {
    247                    decode = true;
    248                }
    249                else if ("-d".equalsIgnoreCase(args[i])) {
    250                    decode = true;
    251                }
    252            }
    253
    254            final String filename = args[args.length - 1];
    255            final File file = new File(filename);
    256            if (!file.exists()) {
    257                System.out.println("Error:  file '" + filename + "' doesn't exist!");
    258                System.exit(0);
    259            }
    260
    261            if (decode) {
    262                final char[] encoded = readChars(file);
    263                final byte[] decoded = decode(encoded);
    264                writeBytes(file, decoded);
    265            }
    266            else {
    267                final byte[] decoded = readBytes(file);
    268                final char[] encoded = encode(decoded);
    269                writeChars(file, encoded);
    270            }
    271        }
    272
    273        private static byte[] readBytes(final File file) {
    274            final ByteArrayOutputStream baos = new ByteArrayOutputStream();
    275            try {
    276                final InputStream fis = new FileInputStream(file);
    277                final InputStream is = new BufferedInputStream(fis);
    278
    279                int count;
    280                final byte[] buf = new byte[16384];
    281                while ((count = is.read(buf)) != -1) {
    282                    if (count > 0) {
    283                        baos.write(buf, 0, count);
    284                    }
    285                }
    286                is.close();
    287            }
    288            catch (Exception e) {
    289                e.printStackTrace();
    290            }
    291
    292            return baos.toByteArray();
    293        }
    294
    295        private static char[] readChars(final File file) {
    296            final CharArrayWriter caw = new CharArrayWriter();
    297            try {
    298                final Reader fr = new FileReader(file);
    299                final Reader in = new BufferedReader(fr);
    300                int count;
    301                final char[] buf = new char[16384];
    302                while ((count = in.read(buf)) != -1) {
    303                    if (count > 0) {
    304                        caw.write(buf, 0, count);
    305                    }
    306                }
    307                in.close();
    308            }
    309            catch (Exception e) {
    310                e.printStackTrace();
    311            }
    312
    313            return caw.toCharArray();
    314        }
    315
    316        private static void writeBytes(final File file, final byte[] data) {
    317            try {
    318                final OutputStream fos = new FileOutputStream(file);
    319                final OutputStream os = new BufferedOutputStream(fos);
    320                os.write(data);
    321                os.close();
    322            }
    323            catch (Exception e) {
    324                e.printStackTrace();
    325            }
    326        }
    327
    328        private static void writeChars(final File file, final char[] data) {
    329            try {
    330                final Writer fos = new FileWriter(file);
    331                final Writer os = new BufferedWriter(fos);
    332                os.write(data);
    333                os.close();
    334            }
    335            catch (Exception e) {
    336                e.printStackTrace();
    337            }
    338        }
    339        ///////////////////////////////////////////////////
    340        // end of test code.
    341        ///////////////////////////////////////////////////
    342
    343    }