1 /* 2 * Copyright (c) 2000, 2006, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 // DefaultHandler.java - default implementation of the core handlers. 27 // http://www.saxproject.org 28 // Written by David Megginson 29 // NO WARRANTY! This class is in the public domain. 30 // $Id: DefaultHandler.java,v 1.3 2006/04/13 02:06:32 jeffsuttor Exp $ 31 32 package jdk.internal.org.xml.sax.helpers; 33 34 import java.io.IOException; 35 36 import jdk.internal.org.xml.sax.InputSource; 37 import jdk.internal.org.xml.sax.Locator; 38 import jdk.internal.org.xml.sax.Attributes; 39 import jdk.internal.org.xml.sax.EntityResolver; 40 import jdk.internal.org.xml.sax.DTDHandler; 41 import jdk.internal.org.xml.sax.ContentHandler; 42 import jdk.internal.org.xml.sax.ErrorHandler; 43 import jdk.internal.org.xml.sax.SAXException; 44 import jdk.internal.org.xml.sax.SAXParseException; 45 46 47 /** 48 * Default base class for SAX2 event handlers. 49 * 50 * <blockquote> 51 * <em>This module, both source code and documentation, is in the 52 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em> 53 * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a> 54 * for further information. 55 * </blockquote> 56 * 57 * <p>This class is available as a convenience base class for SAX2 58 * applications: it provides default implementations for all of the 59 * callbacks in the four core SAX2 handler classes:</p> 60 * 61 * <ul> 62 * <li>{@link org.xml.sax.EntityResolver EntityResolver}</li> 63 * <li>{@link org.xml.sax.DTDHandler DTDHandler}</li> 64 * <li>{@link org.xml.sax.ContentHandler ContentHandler}</li> 65 * <li>{@link org.xml.sax.ErrorHandler ErrorHandler}</li> 66 * </ul> 67 * 68 * <p>Application writers can extend this class when they need to 69 * implement only part of an interface; parser writers can 70 * instantiate this class to provide default handlers when the 71 * application has not supplied its own.</p> 72 * 73 * <p>This class replaces the deprecated SAX1 74 * {@link org.xml.sax.HandlerBase HandlerBase} class.</p> 75 * 76 * @since SAX 2.0 77 * @author David Megginson, 78 * @see org.xml.sax.EntityResolver 79 * @see org.xml.sax.DTDHandler 80 * @see org.xml.sax.ContentHandler 81 * @see org.xml.sax.ErrorHandler 82 */ 83 public class DefaultHandler 84 implements EntityResolver, DTDHandler, ContentHandler, ErrorHandler 85 { 86 87 88 //////////////////////////////////////////////////////////////////// 89 // Default implementation of the EntityResolver interface. 90 //////////////////////////////////////////////////////////////////// 91 92 /** 93 * Resolve an external entity. 94 * 95 * <p>Always return null, so that the parser will use the system 96 * identifier provided in the XML document. This method implements 97 * the SAX default behaviour: application writers can override it 98 * in a subclass to do special translations such as catalog lookups 99 * or URI redirection.</p> 100 * 101 * @param publicId The public identifier, or null if none is 102 * available. 103 * @param systemId The system identifier provided in the XML 104 * document. 105 * @return The new input source, or null to require the 106 * default behaviour. 107 * @exception java.io.IOException If there is an error setting 108 * up the new input source. 109 * @exception org.xml.sax.SAXException Any SAX exception, possibly 110 * wrapping another exception. 111 * @see org.xml.sax.EntityResolver#resolveEntity 112 */ 113 public InputSource resolveEntity (String publicId, String systemId) 114 throws IOException, SAXException 115 { 116 return null; 117 } 118 119 120 121 //////////////////////////////////////////////////////////////////// 122 // Default implementation of DTDHandler interface. 123 //////////////////////////////////////////////////////////////////// 124 125 126 /** 127 * Receive notification of a notation declaration. 128 * 129 * <p>By default, do nothing. Application writers may override this 130 * method in a subclass if they wish to keep track of the notations 131 * declared in a document.</p> 132 * 133 * @param name The notation name. 134 * @param publicId The notation public identifier, or null if not 135 * available. 136 * @param systemId The notation system identifier. 137 * @exception org.xml.sax.SAXException Any SAX exception, possibly 138 * wrapping another exception. 139 * @see org.xml.sax.DTDHandler#notationDecl 140 */ 141 public void notationDecl (String name, String publicId, String systemId) 142 throws SAXException 143 { 144 // no op 145 } 146 147 148 /** 149 * Receive notification of an unparsed entity declaration. 150 * 151 * <p>By default, do nothing. Application writers may override this 152 * method in a subclass to keep track of the unparsed entities 153 * declared in a document.</p> 154 * 155 * @param name The entity name. 156 * @param publicId The entity public identifier, or null if not 157 * available. 158 * @param systemId The entity system identifier. 159 * @param notationName The name of the associated notation. 160 * @exception org.xml.sax.SAXException Any SAX exception, possibly 161 * wrapping another exception. 162 * @see org.xml.sax.DTDHandler#unparsedEntityDecl 163 */ 164 public void unparsedEntityDecl (String name, String publicId, 165 String systemId, String notationName) 166 throws SAXException 167 { 168 // no op 169 } 170 171 172 173 //////////////////////////////////////////////////////////////////// 174 // Default implementation of ContentHandler interface. 175 //////////////////////////////////////////////////////////////////// 176 177 178 /** 179 * Receive a Locator object for document events. 180 * 181 * <p>By default, do nothing. Application writers may override this 182 * method in a subclass if they wish to store the locator for use 183 * with other document events.</p> 184 * 185 * @param locator A locator for all SAX document events. 186 * @see org.xml.sax.ContentHandler#setDocumentLocator 187 * @see org.xml.sax.Locator 188 */ 189 public void setDocumentLocator (Locator locator) 190 { 191 // no op 192 } 193 194 195 /** 196 * Receive notification of the beginning of the document. 197 * 198 * <p>By default, do nothing. Application writers may override this 199 * method in a subclass to take specific actions at the beginning 200 * of a document (such as allocating the root node of a tree or 201 * creating an output file).</p> 202 * 203 * @exception org.xml.sax.SAXException Any SAX exception, possibly 204 * wrapping another exception. 205 * @see org.xml.sax.ContentHandler#startDocument 206 */ 207 public void startDocument () 208 throws SAXException 209 { 210 // no op 211 } 212 213 214 /** 215 * Receive notification of the end of the document. 216 * 217 * <p>By default, do nothing. Application writers may override this 218 * method in a subclass to take specific actions at the end 219 * of a document (such as finalising a tree or closing an output 220 * file).</p> 221 * 222 * @exception org.xml.sax.SAXException Any SAX exception, possibly 223 * wrapping another exception. 224 * @see org.xml.sax.ContentHandler#endDocument 225 */ 226 public void endDocument () 227 throws SAXException 228 { 229 // no op 230 } 231 232 233 /** 234 * Receive notification of the start of a Namespace mapping. 235 * 236 * <p>By default, do nothing. Application writers may override this 237 * method in a subclass to take specific actions at the start of 238 * each Namespace prefix scope (such as storing the prefix mapping).</p> 239 * 240 * @param prefix The Namespace prefix being declared. 241 * @param uri The Namespace URI mapped to the prefix. 242 * @exception org.xml.sax.SAXException Any SAX exception, possibly 243 * wrapping another exception. 244 * @see org.xml.sax.ContentHandler#startPrefixMapping 245 */ 246 public void startPrefixMapping (String prefix, String uri) 247 throws SAXException 248 { 249 // no op 250 } 251 252 253 /** 254 * Receive notification of the end of a Namespace mapping. 255 * 256 * <p>By default, do nothing. Application writers may override this 257 * method in a subclass to take specific actions at the end of 258 * each prefix mapping.</p> 259 * 260 * @param prefix The Namespace prefix being declared. 261 * @exception org.xml.sax.SAXException Any SAX exception, possibly 262 * wrapping another exception. 263 * @see org.xml.sax.ContentHandler#endPrefixMapping 264 */ 265 public void endPrefixMapping (String prefix) 266 throws SAXException 267 { 268 // no op 269 } 270 271 272 /** 273 * Receive notification of the start of an element. 274 * 275 * <p>By default, do nothing. Application writers may override this 276 * method in a subclass to take specific actions at the start of 277 * each element (such as allocating a new tree node or writing 278 * output to a file).</p> 279 * 280 * @param uri The Namespace URI, or the empty string if the 281 * element has no Namespace URI or if Namespace 282 * processing is not being performed. 283 * @param localName The local name (without prefix), or the 284 * empty string if Namespace processing is not being 285 * performed. 286 * @param qName The qualified name (with prefix), or the 287 * empty string if qualified names are not available. 288 * @param attributes The attributes attached to the element. If 289 * there are no attributes, it shall be an empty 290 * Attributes object. 291 * @exception org.xml.sax.SAXException Any SAX exception, possibly 292 * wrapping another exception. 293 * @see org.xml.sax.ContentHandler#startElement 294 */ 295 public void startElement (String uri, String localName, 296 String qName, Attributes attributes) 297 throws SAXException 298 { 299 // no op 300 } 301 302 303 /** 304 * Receive notification of the end of an element. 305 * 306 * <p>By default, do nothing. Application writers may override this 307 * method in a subclass to take specific actions at the end of 308 * each element (such as finalising a tree node or writing 309 * output to a file).</p> 310 * 311 * @param uri The Namespace URI, or the empty string if the 312 * element has no Namespace URI or if Namespace 313 * processing is not being performed. 314 * @param localName The local name (without prefix), or the 315 * empty string if Namespace processing is not being 316 * performed. 317 * @param qName The qualified name (with prefix), or the 318 * empty string if qualified names are not available. 319 * @exception org.xml.sax.SAXException Any SAX exception, possibly 320 * wrapping another exception. 321 * @see org.xml.sax.ContentHandler#endElement 322 */ 323 public void endElement (String uri, String localName, String qName) 324 throws SAXException 325 { 326 // no op 327 } 328 329 330 /** 331 * Receive notification of character data inside an element. 332 * 333 * <p>By default, do nothing. Application writers may override this 334 * method to take specific actions for each chunk of character data 335 * (such as adding the data to a node or buffer, or printing it to 336 * a file).</p> 337 * 338 * @param ch The characters. 339 * @param start The start position in the character array. 340 * @param length The number of characters to use from the 341 * character array. 342 * @exception org.xml.sax.SAXException Any SAX exception, possibly 343 * wrapping another exception. 344 * @see org.xml.sax.ContentHandler#characters 345 */ 346 public void characters (char ch[], int start, int length) 347 throws SAXException 348 { 349 // no op 350 } 351 352 353 /** 354 * Receive notification of ignorable whitespace in element content. 355 * 356 * <p>By default, do nothing. Application writers may override this 357 * method to take specific actions for each chunk of ignorable 358 * whitespace (such as adding data to a node or buffer, or printing 359 * it to a file).</p> 360 * 361 * @param ch The whitespace characters. 362 * @param start The start position in the character array. 363 * @param length The number of characters to use from the 364 * character array. 365 * @exception org.xml.sax.SAXException Any SAX exception, possibly 366 * wrapping another exception. 367 * @see org.xml.sax.ContentHandler#ignorableWhitespace 368 */ 369 public void ignorableWhitespace (char ch[], int start, int length) 370 throws SAXException 371 { 372 // no op 373 } 374 375 376 /** 377 * Receive notification of a processing instruction. 378 * 379 * <p>By default, do nothing. Application writers may override this 380 * method in a subclass to take specific actions for each 381 * processing instruction, such as setting status variables or 382 * invoking other methods.</p> 383 * 384 * @param target The processing instruction target. 385 * @param data The processing instruction data, or null if 386 * none is supplied. 387 * @exception org.xml.sax.SAXException Any SAX exception, possibly 388 * wrapping another exception. 389 * @see org.xml.sax.ContentHandler#processingInstruction 390 */ 391 public void processingInstruction (String target, String data) 392 throws SAXException 393 { 394 // no op 395 } 396 397 398 /** 399 * Receive notification of a skipped entity. 400 * 401 * <p>By default, do nothing. Application writers may override this 402 * method in a subclass to take specific actions for each 403 * processing instruction, such as setting status variables or 404 * invoking other methods.</p> 405 * 406 * @param name The name of the skipped entity. 407 * @exception org.xml.sax.SAXException Any SAX exception, possibly 408 * wrapping another exception. 409 * @see org.xml.sax.ContentHandler#processingInstruction 410 */ 411 public void skippedEntity (String name) 412 throws SAXException 413 { 414 // no op 415 } 416 417 418 419 //////////////////////////////////////////////////////////////////// 420 // Default implementation of the ErrorHandler interface. 421 //////////////////////////////////////////////////////////////////// 422 423 424 /** 425 * Receive notification of a parser warning. 426 * 427 * <p>The default implementation does nothing. Application writers 428 * may override this method in a subclass to take specific actions 429 * for each warning, such as inserting the message in a log file or 430 * printing it to the console.</p> 431 * 432 * @param e The warning information encoded as an exception. 433 * @exception org.xml.sax.SAXException Any SAX exception, possibly 434 * wrapping another exception. 435 * @see org.xml.sax.ErrorHandler#warning 436 * @see org.xml.sax.SAXParseException 437 */ 438 public void warning (SAXParseException e) 439 throws SAXException 440 { 441 // no op 442 } 443 444 445 /** 446 * Receive notification of a recoverable parser error. 447 * 448 * <p>The default implementation does nothing. Application writers 449 * may override this method in a subclass to take specific actions 450 * for each error, such as inserting the message in a log file or 451 * printing it to the console.</p> 452 * 453 * @param e The error information encoded as an exception. 454 * @exception org.xml.sax.SAXException Any SAX exception, possibly 455 * wrapping another exception. 456 * @see org.xml.sax.ErrorHandler#warning 457 * @see org.xml.sax.SAXParseException 458 */ 459 public void error (SAXParseException e) 460 throws SAXException 461 { 462 // no op 463 } 464 465 466 /** 467 * Report a fatal XML parsing error. 468 * 469 * <p>The default implementation throws a SAXParseException. 470 * Application writers may override this method in a subclass if 471 * they need to take specific actions for each fatal error (such as 472 * collecting all of the errors into a single report): in any case, 473 * the application must stop all regular processing when this 474 * method is invoked, since the document is no longer reliable, and 475 * the parser may no longer report parsing events.</p> 476 * 477 * @param e The error information encoded as an exception. 478 * @exception org.xml.sax.SAXException Any SAX exception, possibly 479 * wrapping another exception. 480 * @see org.xml.sax.ErrorHandler#fatalError 481 * @see org.xml.sax.SAXParseException 482 */ 483 public void fatalError (SAXParseException e) 484 throws SAXException 485 { 486 throw e; 487 } 488 489 } 490 491 // end of DefaultHandler.java