Java tutorial
/* $HeadURL:: $ * $Id$ * * Copyright (c) 2006-2010 by Public Library of Science * http://plos.org * http://ambraproject.org * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.topazproject.xml.transform; import javax.xml.parsers.SAXParserFactory; import javax.xml.transform.Source; import javax.xml.transform.sax.SAXSource; import org.xml.sax.helpers.XMLReaderFactory; import org.xml.sax.EntityResolver; import org.xml.sax.InputSource; import org.xml.sax.XMLReader; import org.xml.sax.SAXException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * Creates a {@link Source} that can be used in a {@link javax.xml.transform.Transformer#transform} * call with a custom entity resolver. * * @author Eric Brown and Ronald Tschalr * @version $Id$ */ public class EntityResolvingSource extends SAXSource implements Source { private static final Log log = LogFactory.getLog(EntityResolvingSource.class); private static final String xmlReaderCName; static { /* Remember the name of the XMLReader class so we can use it in the XMLReaderFactory * call. Note that we don't set the org.xml.sax.driver property because there seem to * be cases where that property is removed again. */ String cname = null; try { cname = SAXParserFactory.newInstance().newSAXParser().getXMLReader().getClass().getName(); log.info("Using XMLReader: " + cname); } catch (Exception e) { log.warn("Failed to get the XMLReader class", e); } xmlReaderCName = cname; } /** * Construct a new EntityResolvingSource object. * * @param src is the source of the XML document * @param resolver is the custom resolver * @throws SAXException if we're unable to create an XMLReader (Should never happen * unless there is a serious initialization problem that is likely the result * of a mis-configuration of the JDK. Multiple errors will likely be logged.) */ public EntityResolvingSource(InputSource src, EntityResolver resolver) throws SAXException { super(createXMLReader(resolver), src); if (log.isDebugEnabled()) log.debug("Created " + this.getClass().getName() + " w/" + resolver.getClass().getName()); } private static XMLReader createXMLReader(EntityResolver resolver) throws SAXException { try { XMLReader rdr = XMLReaderFactory.createXMLReader(xmlReaderCName); rdr.setEntityResolver(resolver); return rdr; } catch (SAXException se) { log.error("Unable to create XMLReader from " + xmlReaderCName, se); throw se; } } }