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42 package org.jfree.xml.util;
43
44 import java.io.BufferedInputStream  ;
45 import java.io.BufferedOutputStream ;
46 import java.io.BufferedReader ;
47 import java.io.BufferedWriter ;
48 import java.io.ByteArrayOutputStream ;
49 import java.io.CharArrayWriter ;
50 import java.io.File ;
51 import java.io.FileInputStream ;
52 import java.io.FileOutputStream ;
53 import java.io.FileReader ;
54 import java.io.FileWriter ;
55 import java.io.InputStream ;
56 import java.io.OutputStream ;
57 import java.io.Reader ;
58 import java.io.Writer ;
59
60
70 public class Base64 {
71
72 private Base64 ()
73 {
74 }
75
76
83 public static char[] encode(final byte[] data) {
84 final char[] out = new char[((data.length + 2) / 3) * 4];
85
86 for (int i = 0, index = 0; i < data.length; i += 3, index += 4) {
91 boolean quad = false;
92 boolean trip = false;
93
94 int val = (0xFF & data[i]);
95 val <<= 8;
96 if ((i + 1) < data.length) {
97 val |= (0xFF & data[i + 1]);
98 trip = true;
99 }
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
131 public static byte[] decode(final char[] data) {
132
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; }
144 }
145
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; int accum = 0; int index = 0;
164
165 for (int ix = 0; ix < data.length; ix++) {
167 final int value = (data[ix] > 255) ? -1 : codes[data[ix]];
168
169 if (value >= 0) { accum <<= 6; shift += 6; accum |= value; if (shift >= 8) { shift -= 8; out[index++] = (byte) ((accum >> shift) & 0xff);
177 }
178 }
179 }
186
187 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 private static char[] alphabet =
201 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=".toCharArray();
202
203 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
233
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
343 }
344
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