Java tutorial
/** * This file Copyright (c) 2011-2012 Magnolia International * Ltd. (http://www.magnolia-cms.com). All rights reserved. * * * This file is dual-licensed under both the Magnolia * Network Agreement and the GNU General Public License. * You may elect to use one or the other of these licenses. * * This file is distributed in the hope that it will be * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the * implied warranty of MERCHANTABILITY or FITNESS FOR A * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT. * Redistribution, except as permitted by whichever of the GPL * or MNA you select, is prohibited. * * 1. For the GPL license (GPL), you can redistribute and/or * modify this file under the terms of the GNU General * Public License, Version 3, as published by the Free Software * Foundation. You should have received a copy of the GNU * General Public License, Version 3 along with this program; * if not, write to the Free Software Foundation, Inc., 51 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * 2. For the Magnolia Network Agreement (MNA), this file * and the accompanying materials are made available under the * terms of the MNA which accompanies this distribution, and * is available at http://www.magnolia-cms.com/mna.html * * Any modifications to this file must keep this entire header * intact. * */ package info.magnolia.objectfactory.configuration; import java.beans.IntrospectionException; import java.io.IOException; import java.io.InputStreamReader; import java.io.Reader; import java.io.StringReader; import java.io.StringWriter; import java.net.URL; import java.util.ArrayList; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern; import org.apache.commons.betwixt.io.BeanReader; import org.apache.commons.io.IOUtils; import org.jdom.DocType; import org.jdom.Document; import org.jdom.JDOMException; import org.jdom.input.SAXBuilder; import org.jdom.output.XMLOutputter; import org.xml.sax.SAXException; import org.xml.sax.SAXParseException; import info.magnolia.module.model.ComponentsDefinition; /** * Reads components defined in xml. * * @version $Id$ * @see ComponentsDefinition */ public class ComponentConfigurationReader { private static final org.slf4j.Logger log = org.slf4j.LoggerFactory .getLogger(ComponentConfigurationReader.class); private static final String DTD = "/info/magnolia/module/model/components.dtd"; private final String dtdUrl; private final BeanReader beanReader; public ComponentConfigurationReader() { final URL dtd = getClass().getResource(DTD); if (dtd == null) { throw new ComponentConfigurationException("DTD not found at " + DTD); } dtdUrl = dtd.toString(); beanReader = new BeanReader(); try { beanReader.setValidating(true); beanReader.setErrorHandler(new ErrorHandler()); beanReader.registerBeanClass(ComponentsDefinition.class); } catch (IntrospectionException e) { throw new ComponentConfigurationException(e); } } public List<ComponentsDefinition> readAll(List<String> resourcePaths) { List<ComponentsDefinition> componentsDefinitions = new ArrayList<ComponentsDefinition>(); for (String resourcePath : resourcePaths) { log.debug("Parsing components file {}", resourcePath); ComponentsDefinition componentsDefinition = readFromResource(resourcePath); componentsDefinitions.add(componentsDefinition); } return componentsDefinitions; } public ComponentsDefinition read(Reader in) { try { final Reader replacedDtd = replaceDtd(in); return (ComponentsDefinition) beanReader.parse(replacedDtd); } catch (IOException e) { throw new ComponentConfigurationException("Can't read components definition file: " + e.getMessage(), e); } catch (SAXException e) { throw new ComponentConfigurationException(e.getMessage(), e); } } public ComponentsDefinition readFromResource(String resourcePath) { final InputStreamReader reader = new InputStreamReader(getClass().getResourceAsStream(resourcePath)); try { return read(reader); } finally { try { reader.close(); } catch (IOException e) { log.error("Can't close input for " + resourcePath); } } } /** * @deprecated TODO very ugly hack to force documents to be validated against OUR DTD. * We could use an EntityResolver, but it seems that with SAX, the documents will only be * validated if they original have a doctype declaration. * We could also use http://doctypechanger.sourceforge.net/ * ... or switch to XmlSchema. */ private Reader replaceDtd(Reader reader) throws IOException { String content = IOUtils.toString(reader); // remove doctype Pattern pattern = Pattern.compile("<!DOCTYPE .*>"); Matcher matcher = pattern.matcher(content); content = matcher.replaceFirst(""); // set doctype to the dtd try { Document doc = new SAXBuilder().build(new StringReader(content)); doc.setDocType(new DocType("components", dtdUrl)); // write the xml to the string XMLOutputter outputter = new XMLOutputter(); StringWriter writer = new StringWriter(); outputter.output(doc, writer); final String replacedDtd = writer.toString(); return new StringReader(replacedDtd); } catch (JDOMException e) { throw new ComponentConfigurationException(e); } } private static class ErrorHandler implements org.xml.sax.ErrorHandler { @Override public void warning(SAXParseException e) throws SAXException { log.warn("Warning on components definition " + getSaxParseExceptionMessage(e)); } @Override public void error(SAXParseException e) throws SAXException { throw new SAXException("Invalid components definition file, error " + getSaxParseExceptionMessage(e), e); } @Override public void fatalError(SAXParseException e) throws SAXException { throw new SAXException( "Invalid components definition file, fatal error " + getSaxParseExceptionMessage(e), e); } } private static String getSaxParseExceptionMessage(SAXParseException e) { return "at line " + e.getLineNumber() + " column " + e.getColumnNumber() + ": " + e.getMessage(); } }