Java tutorial
/* * JBoss, Home of Professional Open Source * Copyright 2005, JBoss Inc., and individual contributors as indicated * by the @authors tag. See the copyright.txt in the distribution for a * full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jbpm.jpdl.internal.convert; import java.io.Serializable; import java.net.URL; import java.util.ArrayList; import java.util.HashSet; import java.util.Iterator; import java.util.List; import java.util.Set; import javax.xml.parsers.SAXParser; import javax.xml.parsers.SAXParserFactory; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.dom4j.Document; import org.dom4j.io.SAXReader; import org.jbpm.jpdl.internal.convert.problem.Problem; import org.jbpm.jpdl.internal.convert.problem.ProblemListener; import org.xml.sax.ErrorHandler; import org.xml.sax.InputSource; import org.xml.sax.SAXException; import org.xml.sax.SAXParseException; import org.xml.sax.XMLReader; /** * Validate an XML document using JAXP techniques and an XML Schema. This helper * class wraps the processing of a schema to aid in schema validation throughout * the product. * * orginal authors: * @author Tom Baeyens * @author Jim Rigsbee */ public class Jpdl3ConverterParser implements Serializable { private static final long serialVersionUID = 1L; static SAXParserFactory saxParserFactory = createSaxParserFactory(); private static Set schemaResources = getDefaultSchemaResources(); private static Object schemaSource; public static Document parse(InputSource inputSource, ProblemListener problemListener) throws Exception { Document document = null; SAXReader saxReader = createSaxReader(problemListener); document = saxReader.read(inputSource); return document; } public static SAXReader createSaxReader(ProblemListener problemListener) throws Exception { XMLReader xmlReader = createXmlReader(); SAXReader saxReader = new SAXReader(xmlReader); saxReader.setErrorHandler(new JpdlErrorHandler(problemListener)); return saxReader; } public static XMLReader createXmlReader() throws Exception { SAXParser saxParser = saxParserFactory.newSAXParser(); XMLReader xmlReader = saxParser.getXMLReader(); try { saxParser.setProperty("http://java.sun.com/xml/jaxp/properties/schemaLanguage", "http://www.w3.org/2001/XMLSchema"); } catch (SAXException e) { log.warn("couldn't set schema language property", e); } try { saxParser.setProperty("http://java.sun.com/xml/jaxp/properties/schemaSource", getSchemaSource()); } catch (SAXException e) { log.warn("couldn't set schema source property", e); } try { xmlReader.setFeature("http://apache.org/xml/features/validation/dynamic", true); } catch (SAXException e) { log.warn("couldn't set dynamic validation feature", e); } return xmlReader; } private static Object getSchemaSource() { if (schemaSource == null) { List schemaLocations = new ArrayList(schemaResources.size()); for (Iterator i = schemaResources.iterator(); i.hasNext();) { String schemaResource = (String) i.next(); URL schemaURL = Jpdl3ConverterParser.class.getClassLoader().getResource(schemaResource); if (schemaURL != null) { String schemaLocation = schemaURL.toString(); if (log.isDebugEnabled()) { log.debug("schema resource found: " + schemaResource); } schemaLocations.add(schemaLocation); } } schemaSource = schemaLocations.toArray(new String[schemaLocations.size()]); } return schemaSource; } static class JpdlErrorHandler implements ErrorHandler, Serializable { private ProblemListener problemListener = null; private static final long serialVersionUID = 1L; JpdlErrorHandler(ProblemListener problemListener) { this.problemListener = problemListener; } public void warning(SAXParseException pe) { addProblem(Problem.LEVEL_WARNING, pe); } public void error(SAXParseException pe) { addProblem(Problem.LEVEL_ERROR, pe); } public void fatalError(SAXParseException pe) { addProblem(Problem.LEVEL_FATAL, pe); } private void addProblem(int level, SAXParseException pe) { Problem problem = new Problem(level, pe.getMessage(), pe); problem.setResource(pe.getSystemId()); int line = pe.getLineNumber(); if (line != -1) problem.setLine(new Integer(line)); problemListener.addProblem(problem); } } public static void addSchemaResource(String resource) { schemaResources.add(resource); schemaSource = null; } private static Set getDefaultSchemaResources() { Set schemaResources = new HashSet(); schemaResources.add("org/jbpm/jpdl/xml/jpdl-3.0.xsd"); schemaResources.add("org/jbpm/jpdl/xml/jpdl-3.1.xsd"); schemaResources.add("org/jbpm/jpdl/xml/jpdl-3.2.xsd"); schemaResources.add("org/jbpm/jpdl/xml/jpdl-3.3.xsd"); schemaResources.add("org/jboss/seam/pageflow-2.0.xsd"); return schemaResources; } private static SAXParserFactory createSaxParserFactory() { SAXParserFactory saxParserFactory = SAXParserFactory.newInstance(); saxParserFactory.setValidating(true); saxParserFactory.setNamespaceAware(true); return saxParserFactory; } private static final Log log = LogFactory.getLog(Jpdl3ConverterParser.class); }