1 /* BASE.java -- 2 Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc. 3 4 This file is part of GNU Classpath. 5 6 GNU Classpath is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 GNU Classpath is distributed in the hope that it will be useful, but 12 WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GNU Classpath; see the file COPYING. If not, write to the 18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 19 02110-1301 USA. 20 21 Linking this library statically or dynamically with other modules is 22 making a combined work based on this library. Thus, the terms and 23 conditions of the GNU General Public License cover the whole 24 combination. 25 26 As a special exception, the copyright holders of this library give you 27 permission to link this library with independent modules to produce an 28 executable, regardless of the license terms of these independent 29 modules, and to copy and distribute the resulting executable under 30 terms of your choice, provided that you also meet, for each linked 31 independent module, the terms and conditions of the license of that 32 module. An independent module is a module which is not derived from 33 or based on this library. If you modify this library, you may extend 34 this exception to your version of the library, but you are not 35 obligated to do so. If you do not wish to do so, delete this 36 exception statement from your version. */ 37 38 39 package gnu.java.net; 40 41 /** 42 * Encodes and decodes text according to the BASE64 encoding. 43 * 44 * @author Chris Burdess (dog@gnu.org) 45 */ 46 public final class BASE64 47 { 48 private static final byte[] src = { 49 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 50 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x52, 0x53, 0x54, 51 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x61, 0x62, 0x63, 0x64, 52 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 53 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 54 0x79, 0x7a, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 55 0x38, 0x39, 0x2b, 0x2f 56 }; 57 58 private static final byte[] dst; 59 static 60 { 61 dst = new byte[0x100]; 62 for (int i = 0x0; i < 0xff; i++) 63 { 64 dst[i] = -1; 65 } 66 for (int i = 0; i < src.length; i++) 67 { 68 dst[src[i]] = (byte) i; 69 } 70 } 71 BASE64()72 private BASE64() 73 { 74 } 75 76 /** 77 * Encode the specified byte array using the BASE64 algorithm. 78 * 79 * @param bs the source byte array 80 */ encode(byte[] bs)81 public static byte[] encode(byte[] bs) 82 { 83 int si = 0, ti = 0; // source/target array indices 84 byte[] bt = new byte[((bs.length + 2) * 4) / 3]; // target byte array 85 for (; si < bs.length; si += 3) 86 { 87 int buflen = bs.length - si; 88 if (buflen == 1) 89 { 90 byte b = bs[si]; 91 int i = 0; 92 bt[ti++] = src[b >>> 2 & 0x3f]; 93 bt[ti++] = src[(b << 4 & 0x30) + (i >>> 4 & 0xf)]; 94 } 95 else if (buflen == 2) 96 { 97 byte b1 = bs[si], b2 = bs[si + 1]; 98 int i = 0; 99 bt[ti++] = src[b1 >>> 2 & 0x3f]; 100 bt[ti++] = src[(b1 << 4 & 0x30) + (b2 >>> 4 & 0xf)]; 101 bt[ti++] = src[(b2 << 2 & 0x3c) + (i >>> 6 & 0x3)]; 102 } 103 else 104 { 105 byte b1 = bs[si], b2 = bs[si + 1], b3 = bs[si + 2]; 106 bt[ti++] = src[b1 >>> 2 & 0x3f]; 107 bt[ti++] = src[(b1 << 4 & 0x30) + (b2 >>> 4 & 0xf)]; 108 bt[ti++] = src[(b2 << 2 & 0x3c) + (b3 >>> 6 & 0x3)]; 109 bt[ti++] = src[b3 & 0x3f]; 110 } 111 } 112 if (ti < bt.length) 113 { 114 byte[] tmp = new byte[ti]; 115 System.arraycopy(bt, 0, tmp, 0, ti); 116 bt = tmp; 117 } 118 /*while (ti < bt.length) 119 { 120 bt[ti++] = 0x3d; 121 }*/ 122 return bt; 123 } 124 125 /** 126 * Decode the specified byte array using the BASE64 algorithm. 127 * 128 * @param bs the source byte array 129 */ decode(byte[] bs)130 public static byte[] decode(byte[] bs) 131 { 132 int srclen = bs.length; 133 while (srclen > 0 && bs[srclen - 1] == 0x3d) 134 { 135 srclen--; /* strip padding character */ 136 } 137 byte[] buffer = new byte[srclen]; 138 int buflen = 0; 139 int si = 0; 140 int len = srclen - si; 141 while (len > 0) 142 { 143 byte b0 = dst[bs[si++] & 0xff]; 144 byte b2 = dst[bs[si++] & 0xff]; 145 buffer[buflen++] = (byte) (b0 << 2 & 0xfc | b2 >>> 4 & 0x3); 146 if (len > 2) 147 { 148 b0 = b2; 149 b2 = dst[bs[si++] & 0xff]; 150 buffer[buflen++] = (byte) (b0 << 4 & 0xf0 | b2 >>> 2 & 0xf); 151 if (len > 3) 152 { 153 b0 = b2; 154 b2 = dst[bs[si++] & 0xff]; 155 buffer[buflen++] = (byte) (b0 << 6 & 0xc0 | b2 & 0x3f); 156 } 157 } 158 len = srclen - si; 159 } 160 byte[] bt = new byte[buflen]; 161 System.arraycopy(buffer, 0, bt, 0, buflen); 162 return bt; 163 } 164 main(String[] args)165 public static void main(String[] args) 166 { 167 boolean decode = false; 168 for (int i = 0; i < args.length; i++) 169 { 170 if (args[i].equals("-d")) 171 { 172 decode = true; 173 } 174 else 175 { 176 try 177 { 178 byte[] in = args[i].getBytes("US-ASCII"); 179 byte[] out = decode ? decode(in) : encode(in); 180 System.out.println(args[i] + " = " + 181 new String(out, "US-ASCII")); 182 } 183 catch (java.io.UnsupportedEncodingException e) 184 { 185 e.printStackTrace(System.err); 186 } 187 } 188 } 189 } 190 } 191