mike ritter | 6934ac1 | 2009-09-22 14:38:51 -0700 | [diff] [blame] | 1 | /** |
| 2 | * Copyright (c) 2004-2006 Regents of the University of California. |
| 3 | All rights reserved. |
| 4 | |
| 5 | Redistribution and use in source and binary forms, with or without |
| 6 | modification, are permitted provided that the following conditions |
| 7 | are met: |
| 8 | |
| 9 | 1. Redistributions of source code must retain the above copyright |
| 10 | notice, this list of conditions and the following disclaimer. |
| 11 | |
| 12 | 2. Redistributions in binary form must reproduce the above copyright |
| 13 | notice and this list of conditions. |
| 14 | |
| 15 | 3. The name of the University may not be used to endorse or promote products |
| 16 | derived from this software without specific prior written permission. |
| 17 | |
| 18 | THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 19 | ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 20 | IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 21 | ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 22 | FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 23 | DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 24 | OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 25 | HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 26 | LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 27 | OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 28 | SUCH DAMAGE. |
| 29 | */ |
| 30 | |
| 31 | package org.jheer; |
| 32 | |
| 33 | //import java.io.PrintWriter; |
| 34 | import java.io.FileWriter; |
| 35 | import java.io.IOException; |
| 36 | import java.util.ArrayList; |
| 37 | |
| 38 | /** |
| 39 | * Utility class for writing XML files. This class provides convenience |
| 40 | * methods for creating XML documents, such as starting and ending |
| 41 | * tags, and adding content and comments. This class handles correct |
| 42 | * XML formatting and will properly escape text to ensure that the |
| 43 | * text remains valid XML. |
| 44 | * |
| 45 | * <p>To use this class, create a new instance with the desired |
| 46 | * [Print]FileWriter to write the XML to. Call the {@link #begin()} or |
| 47 | * {@link #begin(String, int)} method when ready to start outputting |
| 48 | * XML. Then use the provided methods to generate the XML file. |
| 49 | * Finally, call either the {@link #finish()} or {@link #finish(String)} |
| 50 | * methods to signal the completion of the file.</p> |
| 51 | * |
| 52 | * @author <a href="http://jheer.org">jeffrey heer</a> |
| 53 | * |
| 54 | * Modified to take a FileWriter and now throws IOException. |
| 55 | */ |
| 56 | |
| 57 | public class XMLWriter { |
| 58 | |
| 59 | // private PrintWriter m_out; |
| 60 | private FileWriter m_out; |
| 61 | private int m_bias = 0; |
| 62 | private int m_tab; |
| 63 | private ArrayList m_tagStack = new ArrayList(); |
| 64 | |
| 65 | /** |
| 66 | * Create a new XMLWriter. |
| 67 | * @param out the FileWriter to write the XML to |
| 68 | */ |
| 69 | // public XMLWriter(PrintWriter out) { |
| 70 | public XMLWriter(FileWriter out) { |
| 71 | this(out, 2); |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * Create a new XMLWriter. |
| 76 | * @param out the FileWriter to write the XML to |
| 77 | * @param tabLength the number of spaces to use for each |
| 78 | * level of indentation in the XML file |
| 79 | */ |
| 80 | // public XMLWriter(PrintWriter out, int tabLength) { |
| 81 | public XMLWriter(FileWriter out, int tabLength) { |
| 82 | m_out = out; |
| 83 | m_tab = 2; |
| 84 | } |
| 85 | |
| 86 | /** |
| 87 | * Write <em>unescaped</em> text into the XML file. To write |
| 88 | * escaped text, use the {@link #content(String)} method instead. |
| 89 | * @param s the text to write. This String will not be escaped. |
| 90 | */ |
| 91 | public void write(String s) throws IOException { |
| 92 | m_out.write(s); |
| 93 | } |
| 94 | |
| 95 | /** |
| 96 | * Write <em>unescaped</em> text into the XML file, followed by |
| 97 | * a newline. To write escaped text, use the {@link #content(String)} |
| 98 | * method instead. |
| 99 | * @param s the text to write. This String will not be escaped. |
| 100 | */ |
| 101 | public void writeln(String s) throws IOException { |
| 102 | m_out.write(s); |
| 103 | m_out.write("\n"); |
| 104 | } |
| 105 | |
| 106 | /** |
| 107 | * Write a newline into the XML file. |
| 108 | */ |
| 109 | public void writeln() throws IOException { |
| 110 | m_out.write("\n"); |
| 111 | } |
| 112 | |
| 113 | /** |
| 114 | * Begin the XML document. This must be called before any other |
| 115 | * formatting methods. This method writes an XML header into |
| 116 | * the top of the output stream. |
| 117 | */ |
| 118 | public void begin() throws IOException { |
| 119 | m_out.write("<?xml version=\"1.0\" encoding=\"UTF-8\"?>"); |
| 120 | writeln(); |
| 121 | } |
| 122 | |
| 123 | /** |
| 124 | * Begin the XML document. This must be called before any other |
| 125 | * formatting methods. This method writes an XML header into |
| 126 | * the top of the output stream, plus additional header text |
| 127 | * provided by the client |
| 128 | * @param header header text to insert into the document |
| 129 | * @param bias the spacing bias to use for all subsequent indenting |
| 130 | */ |
| 131 | public void begin(String header, int bias) throws IOException { |
| 132 | begin(); |
| 133 | m_out.write(header); |
| 134 | m_bias = bias; |
| 135 | } |
| 136 | |
| 137 | /** |
| 138 | * Write a comment in the XML document. The comment will be written |
| 139 | * according to the current spacing and followed by a newline. |
| 140 | * @param comment the comment text |
| 141 | */ |
| 142 | public void comment(String comment) throws IOException { |
| 143 | spacing(); |
| 144 | m_out.write("<!-- "); |
| 145 | m_out.write(comment); |
| 146 | m_out.write(" -->"); |
| 147 | writeln(); |
| 148 | } |
| 149 | |
| 150 | /** |
| 151 | * Internal method for writing a tag with attributes. |
| 152 | * @param tag the tag name |
| 153 | * @param names the names of the attributes |
| 154 | * @param values the values of the attributes |
| 155 | * @param nattr the number of attributes |
| 156 | * @param close true to close the tag, false to leave it |
| 157 | * open and adjust the spacing |
| 158 | */ |
| 159 | protected void tag(String tag, String[] names, String[] values, |
| 160 | int nattr, boolean close) throws IOException |
| 161 | { |
| 162 | spacing(); |
| 163 | m_out.write('<'); |
| 164 | m_out.write(tag); |
| 165 | for ( int i=0; i<nattr; ++i ) { |
| 166 | m_out.write(' '); |
| 167 | m_out.write(names[i]); |
| 168 | m_out.write('='); |
| 169 | m_out.write('\"'); |
| 170 | escapeString(values[i]); |
| 171 | m_out.write('\"'); |
| 172 | } |
| 173 | if ( close ) m_out.write('/'); |
| 174 | m_out.write('>'); |
| 175 | writeln(); |
| 176 | |
| 177 | if ( !close ) { |
| 178 | m_tagStack.add(tag); |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | /** |
| 183 | * Write a closed tag with attributes. The tag will be followed by a |
| 184 | * newline. |
| 185 | * @param tag the tag name |
| 186 | * @param names the names of the attributes |
| 187 | * @param values the values of the attributes |
| 188 | * @param nattr the number of attributes |
| 189 | */ |
| 190 | public void tag(String tag, String[] names, String[] values, int nattr) throws IOException |
| 191 | { |
| 192 | tag(tag, names, values, nattr, true); |
| 193 | } |
| 194 | |
| 195 | /** |
| 196 | * Write a start tag with attributes. The tag will be followed by a |
| 197 | * newline, and the indentation level will be increased. |
| 198 | * @param tag the tag name |
| 199 | * @param names the names of the attributes |
| 200 | * @param values the values of the attributes |
| 201 | * @param nattr the number of attributes |
| 202 | */ |
| 203 | public void start(String tag, String[] names, String[] values, int nattr) throws IOException |
| 204 | { |
| 205 | tag(tag, names, values, nattr, false); |
| 206 | } |
| 207 | |
| 208 | /** |
| 209 | * Write a new attribut to an existing tag. The attribute will be followed by a newline. |
| 210 | * @param name the name of the attribute |
| 211 | * @param value the value of the attribute |
| 212 | */ |
| 213 | public void addAttribute(String name, String value) throws IOException { |
| 214 | spacing(); |
| 215 | m_out.write(name); |
| 216 | m_out.write('='); |
| 217 | m_out.write('\"'); |
| 218 | escapeString(value); |
| 219 | m_out.write('\"'); |
| 220 | writeln(); |
| 221 | } |
| 222 | |
| 223 | /** |
| 224 | * Internal method for writing a tag with a single attribute. |
| 225 | * @param tag the tag name |
| 226 | * @param name the name of the attribute |
| 227 | * @param value the value of the attribute |
| 228 | * @param close true to close the tag, false to leave it |
| 229 | * open and adjust the spacing |
| 230 | */ |
| 231 | protected void tag(String tag, String name, String value, boolean close) throws IOException { |
| 232 | spacing(); |
| 233 | m_out.write('<'); |
| 234 | m_out.write(tag); |
| 235 | m_out.write(' '); |
| 236 | m_out.write(name); |
| 237 | m_out.write('='); |
| 238 | m_out.write('\"'); |
| 239 | escapeString(value); |
| 240 | m_out.write('\"'); |
| 241 | if ( close ) m_out.write('/'); |
| 242 | m_out.write('>'); |
| 243 | writeln(); |
| 244 | |
| 245 | if ( !close ) { |
| 246 | m_tagStack.add(tag); |
| 247 | } |
| 248 | } |
| 249 | |
| 250 | /** |
| 251 | * Write a closed tag with one attribute. The tag will be followed by a |
| 252 | * newline. |
| 253 | * @param tag the tag name |
| 254 | * @param name the name of the attribute |
| 255 | * @param value the value of the attribute |
| 256 | */ |
| 257 | public void tag(String tag, String name, String value) throws IOException |
| 258 | { |
| 259 | tag(tag, name, value, true); |
| 260 | } |
| 261 | |
| 262 | /** |
| 263 | * Write a start tag with one attribute. The tag will be followed by a |
| 264 | * newline, and the indentation level will be increased. |
| 265 | * @param tag the tag name |
| 266 | * @param name the name of the attribute |
| 267 | * @param value the value of the attribute |
| 268 | */ |
| 269 | public void start(String tag, String name, String value) throws IOException |
| 270 | { |
| 271 | tag(tag, name, value, false); |
| 272 | } |
| 273 | |
| 274 | /** |
| 275 | * Internal method for writing a tag with attributes. |
| 276 | * @param tag the tag name |
| 277 | * @param names the names of the attributes |
| 278 | * @param values the values of the attributes |
| 279 | * @param nattr the number of attributes |
| 280 | * @param close true to close the tag, false to leave it |
| 281 | * open and adjust the spacing |
| 282 | */ |
| 283 | protected void tag(String tag, ArrayList names, ArrayList values, |
| 284 | int nattr, boolean close) throws IOException |
| 285 | { |
| 286 | spacing(); |
| 287 | m_out.write('<'); |
| 288 | m_out.write(tag); |
| 289 | for ( int i=0; i<nattr; ++i ) { |
| 290 | m_out.write(' '); |
| 291 | m_out.write((String)names.get(i)); |
| 292 | m_out.write('='); |
| 293 | m_out.write('\"'); |
| 294 | escapeString((String)values.get(i)); |
| 295 | m_out.write('\"'); |
| 296 | } |
| 297 | if ( close ) m_out.write('/'); |
| 298 | m_out.write('>'); |
| 299 | writeln(); |
| 300 | |
| 301 | if ( !close ) { |
| 302 | m_tagStack.add(tag); |
| 303 | } |
| 304 | } |
| 305 | |
| 306 | /** |
| 307 | * Write a closed tag with attributes. The tag will be followed by a |
| 308 | * newline. |
| 309 | * @param tag the tag name |
| 310 | * @param names the names of the attributes |
| 311 | * @param values the values of the attributes |
| 312 | * @param nattr the number of attributes |
| 313 | */ |
| 314 | public void tag(String tag, ArrayList names, ArrayList values, int nattr) throws IOException |
| 315 | { |
| 316 | tag(tag, names, values, nattr, true); |
| 317 | } |
| 318 | |
| 319 | /** |
| 320 | * Write a start tag with attributes. The tag will be followed by a |
| 321 | * newline, and the indentation level will be increased. |
| 322 | * @param tag the tag name |
| 323 | * @param names the names of the attributes |
| 324 | * @param values the values of the attributes |
| 325 | * @param nattr the number of attributes |
| 326 | */ |
| 327 | public void start(String tag, ArrayList names, ArrayList values, int nattr) throws IOException |
| 328 | { |
| 329 | tag(tag, names, values, nattr, false); |
| 330 | } |
| 331 | |
| 332 | /** |
| 333 | * Write a start tag without attributes. The tag will be followed by a |
| 334 | * newline, and the indentation level will be increased. |
| 335 | * @param tag the tag name |
| 336 | */ |
| 337 | public void start(String tag) throws IOException { |
| 338 | tag(tag, (String[])null, null, 0, false); |
| 339 | } |
| 340 | |
| 341 | /** |
| 342 | * Close the most recently opened tag. The tag will be followed by a |
| 343 | * newline, and the indentation level will be decreased. |
| 344 | */ |
| 345 | public void end() throws IOException { |
| 346 | String tag = (String)m_tagStack.remove(m_tagStack.size()-1); |
| 347 | spacing(); |
| 348 | m_out.write('<'); |
| 349 | m_out.write('/'); |
| 350 | m_out.write(tag); |
| 351 | m_out.write('>'); |
| 352 | writeln(); |
| 353 | } |
| 354 | |
| 355 | /** |
| 356 | * Write a new content tag with a single attribute, consisting of an |
| 357 | * open tag, content text, and a closing tag, all on one line. |
| 358 | * @param tag the tag name |
| 359 | * @param name the name of the attribute |
| 360 | * @param value the value of the attribute, this text will be escaped |
| 361 | * @param content the text content, this text will be escaped |
| 362 | */ |
| 363 | public void contentTag(String tag, String name, String value, String content) throws IOException |
| 364 | { |
| 365 | spacing(); |
| 366 | m_out.write('<'); m_out.write(tag); m_out.write(' '); |
| 367 | m_out.write(name); m_out.write('='); |
| 368 | m_out.write('\"'); escapeString(value); m_out.write('\"'); |
| 369 | m_out.write('>'); |
| 370 | escapeString(content); |
| 371 | m_out.write('<'); m_out.write('/'); m_out.write(tag); m_out.write('>'); |
| 372 | writeln(); |
| 373 | } |
| 374 | |
| 375 | /** |
| 376 | * Write a new content tag with no attributes, consisting of an |
| 377 | * open tag, content text, and a closing tag, all on one line. |
| 378 | * @param tag the tag name |
| 379 | * @param content the text content, this text will be escaped |
| 380 | */ |
| 381 | public void contentTag(String tag, String content) throws IOException { |
| 382 | spacing(); |
| 383 | m_out.write('<'); m_out.write(tag); m_out.write('>'); |
| 384 | escapeString(content); |
| 385 | m_out.write('<'); m_out.write('/'); m_out.write(tag); m_out.write('>'); |
| 386 | writeln(); |
| 387 | } |
| 388 | |
| 389 | /** |
| 390 | * Write content text. |
| 391 | * @param content the content text, this text will be escaped |
| 392 | */ |
| 393 | public void content(String content) throws IOException { |
| 394 | escapeString(content); |
| 395 | } |
| 396 | |
| 397 | /** |
| 398 | * Finish the XML document. |
| 399 | */ |
| 400 | public void finish() throws IOException { |
| 401 | m_bias = 0; |
| 402 | m_out.flush(); |
| 403 | } |
| 404 | |
| 405 | /** |
| 406 | * Finish the XML document, writing the given footer text at the |
| 407 | * end of the document. |
| 408 | * @param footer the footer text, this will not be escaped |
| 409 | */ |
| 410 | public void finish(String footer) throws IOException { |
| 411 | m_bias = 0; |
| 412 | m_out.write(footer); |
| 413 | m_out.flush(); |
| 414 | } |
| 415 | |
| 416 | /** |
| 417 | * Write the current spacing (determined by the indentation level) |
| 418 | * into the document. This method is used by many of the other |
| 419 | * formatting methods, and so should only need to be called in |
| 420 | * the case of custom text writing outside the mechanisms |
| 421 | * provided by this class. |
| 422 | */ |
| 423 | public void spacing() throws IOException { |
| 424 | int len = m_bias + m_tagStack.size() * m_tab; |
| 425 | for ( int i=0; i<len; ++i ) |
| 426 | m_out.write(' '); |
| 427 | } |
| 428 | |
| 429 | // ------------------------------------------------------------------------ |
| 430 | // Escape Text |
| 431 | |
| 432 | // unicode ranges and valid/invalid characters |
| 433 | private static final char LOWER_RANGE = 0x20; |
| 434 | private static final char UPPER_RANGE = 0x7f; |
| 435 | private static final char[] VALID_CHARS = { 0x9, 0xA, 0xD }; |
| 436 | |
| 437 | private static final char[] INVALID = { '<', '>', '"', '\'', '&' }; |
| 438 | private static final String[] VALID = |
| 439 | { "<", ">", """, "'", "&" }; |
| 440 | |
| 441 | /** |
| 442 | * Escape a string such that it is safe to use in an XML document. |
| 443 | * @param str the string to escape |
| 444 | */ |
| 445 | protected void escapeString(String str) throws IOException { |
| 446 | if ( str == null ) { |
| 447 | m_out.write("null"); |
| 448 | return; |
| 449 | } |
| 450 | |
| 451 | int len = str.length(); |
| 452 | for (int i = 0; i < len; ++i) { |
| 453 | char c = str.charAt(i); |
| 454 | |
| 455 | if ( (c < LOWER_RANGE && c != VALID_CHARS[0] && |
| 456 | c != VALID_CHARS[1] && c != VALID_CHARS[2]) |
| 457 | || (c > UPPER_RANGE) ) |
| 458 | { |
| 459 | // character out of range, escape with character value |
| 460 | m_out.write("&#"); |
| 461 | m_out.write(Integer.toString(c)); |
| 462 | m_out.write(';'); |
| 463 | } else { |
| 464 | boolean valid = true; |
| 465 | // check for invalid characters (e.g., "<", "&", etc) |
| 466 | for (int j=INVALID.length-1; j >= 0; --j ) |
| 467 | { |
| 468 | if ( INVALID[j] == c) { |
| 469 | valid = false; |
| 470 | m_out.write(VALID[j]); |
| 471 | break; |
| 472 | } |
| 473 | } |
| 474 | // if character is valid, don't escape |
| 475 | if (valid) { |
| 476 | m_out.write(c); |
| 477 | } |
| 478 | } |
| 479 | } |
| 480 | } |
| 481 | |
| 482 | } // end of class XMLWriter |
| 483 | |