Java tutorial
/*-- Copyright (C) 2011 Jason Hunter & Brett McLaughlin. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions, and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions, and the disclaimer that follows these conditions in the documentation and/or other materials provided with the distribution. 3. The name "JDOM" must not be used to endorse or promote products derived from this software without prior written permission. For written permission, please contact <request_AT_jdom_DOT_org>. 4. Products derived from this software may not be called "JDOM", nor may "JDOM" appear in their name, without prior written permission from the JDOM Project Management <request_AT_jdom_DOT_org>. In addition, we request (but do not require) that you include in the end-user documentation provided with the redistribution and/or in the software itself an acknowledgement equivalent to the following: "This product includes software developed by the JDOM Project (http://www.jdom.org/)." Alternatively, the acknowledgment may be graphical using the logos available at http://www.jdom.org/images/logos. THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE JDOM AUTHORS OR THE PROJECT CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. This software consists of voluntary contributions made by many individuals on behalf of the JDOM Project and was originally created by Jason Hunter <jhunter_AT_jdom_DOT_org> and Brett McLaughlin <brett_AT_jdom_DOT_org>. For more information on the JDOM Project, please see <http://www.jdom.org/>. */ package org.jdom2.input.sax; import javax.xml.XMLConstants; import javax.xml.parsers.ParserConfigurationException; import javax.xml.parsers.SAXParserFactory; import javax.xml.validation.Schema; import javax.xml.validation.SchemaFactory; import org.xml.sax.SAXException; import org.xml.sax.XMLReader; import org.jdom2.JDOMException; /** * An enumeration of {@link XMLReaderJDOMFactory} that allows for a single * central location to create XMLReaders. The Singletons (members) of this * enumeration can produce the most common XMLReaders: non-validating, XSD * validating, and DocType validating. * <p> * See the {@link org.jdom2.input.sax package documentation} for details of how * to create the SAXParser you desire. * * @see org.jdom2.input.sax * @author Rolf Lear */ public enum XMLReaders implements XMLReaderJDOMFactory { /** * The non-validating singleton */ NONVALIDATING(0), /** * The DTD-validating Singleton */ DTDVALIDATING(1), /** * The XSD-validating Singleton */ XSDVALIDATING(2); private interface FactorySupplier { SAXParserFactory supply() throws Exception; boolean validates(); } private enum NONSingleton implements FactorySupplier { INSTANCE; private final SAXParserFactory factory; NONSingleton() { SAXParserFactory fac = SAXParserFactory.newInstance(); // All JDOM parsers are namespace aware. fac.setNamespaceAware(true); fac.setValidating(false); factory = fac; } @Override public SAXParserFactory supply() throws Exception { return factory; } @Override public boolean validates() { return false; } } private enum DTDSingleton implements FactorySupplier { INSTANCE; private final SAXParserFactory factory; DTDSingleton() { SAXParserFactory fac = SAXParserFactory.newInstance(); // All JDOM parsers are namespace aware. fac.setNamespaceAware(true); // factory is validating (DTD) fac.setValidating(true); factory = fac; } @Override public SAXParserFactory supply() throws Exception { return factory; } @Override public boolean validates() { return true; } } private enum XSDSingleton implements FactorySupplier { INSTANCE; private final Exception failcause; private final SAXParserFactory factory; XSDSingleton() { SAXParserFactory fac = SAXParserFactory.newInstance(); Exception problem = null; // All JDOM parsers are namespace aware. fac.setNamespaceAware(true); // factory is not validating (DTD), but the Reader is validating // (XSD) fac.setValidating(false); try { SchemaFactory sfac = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI); Schema schema = sfac.newSchema(); fac.setSchema(schema); } catch (SAXException se) { // we could not get a validating system, set the fac to null fac = null; problem = se; } catch (IllegalArgumentException iae) { // this system does not support XSD Validation.... which is true // for android! // we could not get a validating system, set the fac to null fac = null; problem = iae; } catch (UnsupportedOperationException uoe) { // SAXParserFactory throws this exception when setSchema is // called. // Therefore every factory throws this exception unless it // overrides // setSchema. A popular example is Apache Xerces // SAXParserFactoryImpl // before version 2.7.0. fac = null; problem = uoe; } factory = fac; failcause = problem; } @Override public SAXParserFactory supply() throws Exception { if (factory == null) { throw failcause; } return factory; } @Override public boolean validates() { return true; } }; /** the actual SAXParserFactory in the respective singletons. */ private final int singletonID; /** Private constructor */ private XMLReaders(int singletonID) { this.singletonID = singletonID; } private FactorySupplier getSupplier() { switch (singletonID) { case 0: return NONSingleton.INSTANCE; case 1: return DTDSingleton.INSTANCE; case 2: return XSDSingleton.INSTANCE; } throw new IllegalStateException("Unknown singletonID: " + singletonID); } /** * Get a new XMLReader from this JAXP-based {@link XMLReaderJDOMFactory}. * <p> * * @return a new XMLReader instance. * @throws JDOMException * if there is a problem creating the XMLReader */ @Override public XMLReader createXMLReader() throws JDOMException { try { FactorySupplier supplier = getSupplier(); return supplier.supply().newSAXParser().getXMLReader(); } catch (SAXException e) { throw new JDOMException("Unable to create a new XMLReader instance", e); } catch (ParserConfigurationException e) { throw new JDOMException("Unable to create a new XMLReader instance", e); } catch (Exception e) { throw new JDOMException("It was not possible to configure a " + "suitable XMLReader to support " + this, e); } } @Override public boolean isValidating() { return getSupplier().validates(); } }