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/* * Copyright (c) 2000, 2006, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ // DefaultHandler.java - default implementation of the core handlers. // http://www.saxproject.org // Written by David Megginson // NO WARRANTY! This class is in the public domain. // $Id: DefaultHandler.java,v 1.3 2006/04/13 02:06:32 jeffsuttor Exp $ package org.xml.sax.helpers; import java.io.IOException; import org.xml.sax.InputSource; import org.xml.sax.Locator; import org.xml.sax.Attributes; import org.xml.sax.EntityResolver; import org.xml.sax.DTDHandler; import org.xml.sax.ContentHandler; import org.xml.sax.ErrorHandler; import org.xml.sax.SAXException; import org.xml.sax.SAXParseException; /** * Default base class for SAX2 event handlers. * * <blockquote> * <em>This module, both source code and documentation, is in the * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em> * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a> * for further information. * </blockquote> * * <p>This class is available as a convenience base class for SAX2 * applications: it provides default implementations for all of the * callbacks in the four core SAX2 handler classes:</p> * * <ul> * <li>{@link org.xml.sax.EntityResolver EntityResolver}</li> * <li>{@link org.xml.sax.DTDHandler DTDHandler}</li> * <li>{@link org.xml.sax.ContentHandler ContentHandler}</li> * <li>{@link org.xml.sax.ErrorHandler ErrorHandler}</li> * </ul> * * <p>Application writers can extend this class when they need to * implement only part of an interface; parser writers can * instantiate this class to provide default handlers when the * application has not supplied its own.</p> * * <p>This class replaces the deprecated SAX1 * {@link org.xml.sax.HandlerBase HandlerBase} class.</p> * * @since 1.4, SAX 2.0 * @author David Megginson, * @see org.xml.sax.EntityResolver * @see org.xml.sax.DTDHandler * @see org.xml.sax.ContentHandler * @see org.xml.sax.ErrorHandler */ public class DefaultHandler implements EntityResolver, DTDHandler, ContentHandler, ErrorHandler { //////////////////////////////////////////////////////////////////// // Default implementation of the EntityResolver interface. //////////////////////////////////////////////////////////////////// /** * Resolve an external entity. * * <p>Always return null, so that the parser will use the system * identifier provided in the XML document. This method implements * the SAX default behaviour: application writers can override it * in a subclass to do special translations such as catalog lookups * or URI redirection.</p> * * @param publicId The public identifier, or null if none is * available. * @param systemId The system identifier provided in the XML * document. * @return The new input source, or null to require the * default behaviour. * @exception java.io.IOException If there is an error setting * up the new input source. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.EntityResolver#resolveEntity */ public InputSource resolveEntity(String publicId, String systemId) throws IOException, SAXException { return null; } //////////////////////////////////////////////////////////////////// // Default implementation of DTDHandler interface. //////////////////////////////////////////////////////////////////// /** * Receive notification of a notation declaration. * * <p>By default, do nothing. Application writers may override this * method in a subclass if they wish to keep track of the notations * declared in a document.</p> * * @param name The notation name. * @param publicId The notation public identifier, or null if not * available. * @param systemId The notation system identifier. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.DTDHandler#notationDecl */ public void notationDecl(String name, String publicId, String systemId) throws SAXException { // no op } /** * Receive notification of an unparsed entity declaration. * * <p>By default, do nothing. Application writers may override this * method in a subclass to keep track of the unparsed entities * declared in a document.</p> * * @param name The entity name. * @param publicId The entity public identifier, or null if not * available. * @param systemId The entity system identifier. * @param notationName The name of the associated notation. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.DTDHandler#unparsedEntityDecl */ public void unparsedEntityDecl(String name, String publicId, String systemId, String notationName) throws SAXException { // no op } //////////////////////////////////////////////////////////////////// // Default implementation of ContentHandler interface. //////////////////////////////////////////////////////////////////// /** * Receive a Locator object for document events. * * <p>By default, do nothing. Application writers may override this * method in a subclass if they wish to store the locator for use * with other document events.</p> * * @param locator A locator for all SAX document events. * @see org.xml.sax.ContentHandler#setDocumentLocator * @see org.xml.sax.Locator */ public void setDocumentLocator(Locator locator) { // no op } /** * Receive notification of the beginning of the document. * * <p>By default, do nothing. Application writers may override this * method in a subclass to take specific actions at the beginning * of a document (such as allocating the root node of a tree or * creating an output file).</p> * * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ContentHandler#startDocument */ public void startDocument() throws SAXException { // no op } /** * Receive notification of the end of the document. * * <p>By default, do nothing. Application writers may override this * method in a subclass to take specific actions at the end * of a document (such as finalising a tree or closing an output * file).</p> * * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ContentHandler#endDocument */ public void endDocument() throws SAXException { // no op } /** * Receive notification of the start of a Namespace mapping. * * <p>By default, do nothing. Application writers may override this * method in a subclass to take specific actions at the start of * each Namespace prefix scope (such as storing the prefix mapping).</p> * * @param prefix The Namespace prefix being declared. * @param uri The Namespace URI mapped to the prefix. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ContentHandler#startPrefixMapping */ public void startPrefixMapping(String prefix, String uri) throws SAXException { // no op } /** * Receive notification of the end of a Namespace mapping. * * <p>By default, do nothing. Application writers may override this * method in a subclass to take specific actions at the end of * each prefix mapping.</p> * * @param prefix The Namespace prefix being declared. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ContentHandler#endPrefixMapping */ public void endPrefixMapping(String prefix) throws SAXException { // no op } /** * Receive notification of the start of an element. * * <p>By default, do nothing. Application writers may override this * method in a subclass to take specific actions at the start of * each element (such as allocating a new tree node or writing * output to a file).</p> * * @param uri The Namespace URI, or the empty string if the * element has no Namespace URI or if Namespace * processing is not being performed. * @param localName The local name (without prefix), or the * empty string if Namespace processing is not being * performed. * @param qName The qualified name (with prefix), or the * empty string if qualified names are not available. * @param attributes The attributes attached to the element. If * there are no attributes, it shall be an empty * Attributes object. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ContentHandler#startElement */ public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException { // no op } /** * Receive notification of the end of an element. * * <p>By default, do nothing. Application writers may override this * method in a subclass to take specific actions at the end of * each element (such as finalising a tree node or writing * output to a file).</p> * * @param uri The Namespace URI, or the empty string if the * element has no Namespace URI or if Namespace * processing is not being performed. * @param localName The local name (without prefix), or the * empty string if Namespace processing is not being * performed. * @param qName The qualified name (with prefix), or the * empty string if qualified names are not available. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ContentHandler#endElement */ public void endElement(String uri, String localName, String qName) throws SAXException { // no op } /** * Receive notification of character data inside an element. * * <p>By default, do nothing. Application writers may override this * method to take specific actions for each chunk of character data * (such as adding the data to a node or buffer, or printing it to * a file).</p> * * @param ch The characters. * @param start The start position in the character array. * @param length The number of characters to use from the * character array. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ContentHandler#characters */ public void characters(char ch[], int start, int length) throws SAXException { // no op } /** * Receive notification of ignorable whitespace in element content. * * <p>By default, do nothing. Application writers may override this * method to take specific actions for each chunk of ignorable * whitespace (such as adding data to a node or buffer, or printing * it to a file).</p> * * @param ch The whitespace characters. * @param start The start position in the character array. * @param length The number of characters to use from the * character array. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ContentHandler#ignorableWhitespace */ public void ignorableWhitespace(char ch[], int start, int length) throws SAXException { // no op } /** * Receive notification of a processing instruction. * * <p>By default, do nothing. Application writers may override this * method in a subclass to take specific actions for each * processing instruction, such as setting status variables or * invoking other methods.</p> * * @param target The processing instruction target. * @param data The processing instruction data, or null if * none is supplied. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ContentHandler#processingInstruction */ public void processingInstruction(String target, String data) throws SAXException { // no op } /** * Receive notification of a skipped entity. * * <p>By default, do nothing. Application writers may override this * method in a subclass to take specific actions for each * processing instruction, such as setting status variables or * invoking other methods.</p> * * @param name The name of the skipped entity. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ContentHandler#processingInstruction */ public void skippedEntity(String name) throws SAXException { // no op } //////////////////////////////////////////////////////////////////// // Default implementation of the ErrorHandler interface. //////////////////////////////////////////////////////////////////// /** * Receive notification of a parser warning. * * <p>The default implementation does nothing. Application writers * may override this method in a subclass to take specific actions * for each warning, such as inserting the message in a log file or * printing it to the console.</p> * * @param e The warning information encoded as an exception. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ErrorHandler#warning * @see org.xml.sax.SAXParseException */ public void warning(SAXParseException e) throws SAXException { // no op } /** * Receive notification of a recoverable parser error. * * <p>The default implementation does nothing. Application writers * may override this method in a subclass to take specific actions * for each error, such as inserting the message in a log file or * printing it to the console.</p> * * @param e The error information encoded as an exception. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ErrorHandler#warning * @see org.xml.sax.SAXParseException */ public void error(SAXParseException e) throws SAXException { // no op } /** * Report a fatal XML parsing error. * * <p>The default implementation throws a SAXParseException. * Application writers may override this method in a subclass if * they need to take specific actions for each fatal error (such as * collecting all of the errors into a single report): in any case, * the application must stop all regular processing when this * method is invoked, since the document is no longer reliable, and * the parser may no longer report parsing events.</p> * * @param e The error information encoded as an exception. * @exception org.xml.sax.SAXException Any SAX exception, possibly * wrapping another exception. * @see org.xml.sax.ErrorHandler#fatalError * @see org.xml.sax.SAXParseException */ public void fatalError(SAXParseException e) throws SAXException { throw e; } } // end of DefaultHandler.java