Java tutorial
/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. * * Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved. * * The contents of this file are subject to the terms of either the GNU * General Public License Version 2 only ("GPL") or the Common Development * and Distribution License("CDDL") (collectively, the "License"). You * may not use this file except in compliance with the License. You can * obtain a copy of the License at * https://glassfish.java.net/public/CDDL+GPL_1_1.html * or packager/legal/LICENSE.txt. See the License for the specific * language governing permissions and limitations under the License. * * When distributing the software, include this License Header Notice in each * file and include the License file at packager/legal/LICENSE.txt. * * GPL Classpath Exception: * Oracle designates this particular file as subject to the "Classpath" * exception as provided by Oracle in the GPL Version 2 section of the License * file that accompanied this code. * * Modifications: * If applicable, add the following below the License Header, with the fields * enclosed by brackets [] replaced by your own identifying information: * "Portions Copyright [year] [name of copyright owner]" * * Contributor(s): * If you wish your version of this file to be governed by only the CDDL or * only the GPL Version 2, indicate your decision by adding "[Contributor] * elects to include this software in this distribution under the [CDDL or GPL * Version 2] license." If you don't indicate a single choice of license, a * recipient has the option to distribute your version of this file under * either the CDDL, the GPL Version 2 or to extend the choice of license to * its licensees as provided above. However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. */ package com.sun.faces.config; import javax.xml.parsers.ParserConfigurationException; import java.net.URL; import java.util.HashMap; import java.util.logging.Level; import java.util.logging.Logger; import org.apache.commons.digester.Digester; import org.apache.commons.logging.impl.NoOpLog; import org.xml.sax.ErrorHandler; import org.xml.sax.InputSource; import org.xml.sax.SAXException; import org.xml.sax.SAXNotRecognizedException; import org.xml.sax.SAXNotSupportedException; import org.xml.sax.SAXParseException; import org.xml.sax.helpers.DefaultHandler; import com.sun.faces.util.ToolsUtil; import org.xml.sax.EntityResolver; /** * <p>A simple factory to hide <code>Digester</code> configuration * details.</p> */ public class DigesterFactory { private static final Logger logger = ToolsUtil.getLogger(ToolsUtil.FACES_LOGGER + ToolsUtil.CONFIG_LOGGER); /** * <p><code>Xerces</code> specific feature to enable both * DTD and Schema validation.</p> */ private static final String XERCES_VALIDATION = "http://xml.org/sax/features/validation"; /** * <p><code>Xerces</code> specific feature to enable both * DTD and Schema validation.</p> */ private static final String XERCES_SCHEMA_VALIDATION = "http://apache.org/xml/features/validation/schema"; /** * <p><code>Xerces</code> specific feature to enabled constraint * validation.</p> */ private static final String XERCES_SCHEMA_CONSTRAINT_VALIDATION = "http://apache.org/xml/features/validation/schema-full-checking"; /** * <p>Custom <code>EntityResolver</code>.</p> */ private static final JsfEntityResolver RESOLVER = new JsfEntityResolver(); /** * <p>Custom <code>ErrorHandler</code>.</p> */ private static final JsfErrorHandler ERROR_HANDLER = new JsfErrorHandler(); /** * <p>Indicates whether or not document validation is * requested or not.</p> */ private boolean validating; /** * <p>The <code>ThreadLocal</code> variable used to record the * VersionListener instance for each processing thread.</p> */ private static ThreadLocal versionListener = new ThreadLocal() { protected Object initialValue() { return (null); } }; // ------------------------------------------------------------ Constructors /** * <p>Creates a new DigesterFactory instance.</p> * @param isValidating - <code>true</code> if the <code>Digester</code> * instance that is ultimately returned should be configured (if possible) * for document validation. If validation is not desired, pass * <code>false</code>. */ private DigesterFactory(boolean isValidating) { validating = isValidating; } // END DigesterFactory // ---------------------------------------------------------- Public Methods /** * <p>Returns a new <code>DigesterFactory</code> instance that will create * a non-validating <code>Digester</code> instance.</p> */ public static DigesterFactory newInstance() { return DigesterFactory.newInstance(false); } // END newInstance /** * <p>Creates a new <code>DigesterFactory</code> instance that will * create a <code>Digester</code> instance where validation depends * on the value of <code>isValidating</code>.</p> * @param isValidating - <code>true</code> if the <code>Digester</code> * instance that is ultimately returned should be configured (if possible) * for document validation. If validation is not desired, pass * <code>false</code>. * @return a new <code>DigesterFactory</code> capable of creating * <code>Digester</code>instances */ public static DigesterFactory newInstance(boolean isValidating) { DigesterFactory result = new DigesterFactory(isValidating); return result; } // END newInstance /** * <p>Creates a new <code>DigesterFactory</code> instance that will * create a <code>Digester</code> instance where validation depends * on the value of <code>isValidating</code>.</p> * @param isValidating - <code>true</code> if the <code>Digester</code> * instance that is ultimately returned should be configured (if possible) * for document validation. If validation is not desired, pass * <code>false</code>. * @param GrammarListener a GrammarListener instance * @return a new <code>DigesterFactory</code> capable of creating * <code>Digester</code>instances */ public static DigesterFactory newInstance(boolean isValidating, VersionListener listener) { DigesterFactory result = new DigesterFactory(isValidating); if (null != listener) { result.RESOLVER.setVersionListener(listener); versionListener.set(listener); } return result; } // END newInstance public static VersionListener getVersionListener() { return ((VersionListener) versionListener.get()); } public static void releaseDigester(Digester toRelease) { RESOLVER.setVersionListener(null); versionListener.set(null); } /** * <p>Creates a new <code>Digester</code> instance configured for use * with JSF.</p> */ public Digester createDigester() { Digester digester = new Digester(); configureDigester(digester); return digester; } // END getDigester /** * <p>Implemented by a class that wants to be called as a * particular configuration file is parsed.</p> * * <p>This interface is implemented as an anonymous inner class * inside ConfigureListener.digester().</p> */ public interface VersionListener { /** * <p>Called from the EntityResolver when we know one of the * XML Grammar elements to which this config file conforms.</p> */ public void takeActionOnGrammar(String grammar); /** * <p>Called from the individual digester beans to cause the * artifact to be associated with the current JSF spec level of * the file being parsed.</p> */ public void takeActionOnArtifact(String artifactName); } // --------------------------------------------------------- Private Methods /** * <p>Configures the provided <code>Digester</code> instance appropriate * for use with JSF.</p> * @param digester - the <code>Digester</code> instance to configure */ private void configureDigester(Digester digester) { digester.setNamespaceAware(true); digester.setUseContextClassLoader(true); digester.setEntityResolver(RESOLVER); digester.setErrorHandler(ERROR_HANDLER); // disable digester log messages digester.setLogger(new NoOpLog()); if (validating) { if (logger.isLoggable(Level.FINE)) { logger.log(Level.FINE, "Attempting to configure Digester to perform" + " document validation."); } // In order to validate using *both* DTD and Schema, certain // Xerces specific features are required. Try to set these // features. If an exception is thrown trying to set these // features, then disable validation. try { digester.setFeature(XERCES_VALIDATION, true); digester.setFeature(XERCES_SCHEMA_VALIDATION, true); digester.setFeature(XERCES_SCHEMA_CONSTRAINT_VALIDATION, true); digester.setValidating(true); } catch (SAXNotSupportedException e) { if (logger.isLoggable(Level.WARNING)) { logger.log(Level.WARNING, "Attempt to set supported feature on XMLReader, " + "but the value provided was not accepted. " + "Validation will be disabledb."); } digester.setValidating(false); } catch (SAXNotRecognizedException e) { if (logger.isLoggable(Level.WARNING)) { logger.log(Level.WARNING, "Attempt to set unsupported feature on XMLReader" + " necessary for validation. Validation will be" + "disabled."); } digester.setValidating(false); } catch (ParserConfigurationException e) { if (logger.isLoggable(Level.WARNING)) { logger.log(Level.WARNING, "Digester unable to configure underlying parser." + " Validation will be disabled."); } digester.setValidating(false); } } else { digester.setValidating(false); } } // END configureDigester // ----------------------------------------------------------- Inner Classes private static class JsfEntityResolver extends DefaultHandler { /** * <p>Contains associations between grammar name and the physical * resource.</p> */ private static final String[][] DTD_SCHEMA_INFO = { { "web-facesconfig_1_0.dtd", "/com/sun/faces/web-facesconfig_1_0.dtd" }, { "web-facesconfig_1_1.dtd", "/com/sun/faces/web-facesconfig_1_1.dtd" }, { "web-facesconfig_1_2.xsd", "/com/sun/faces/web-facesconfig_1_2.xsd" }, { "web-facesconfig_2_0.xsd", "/com/sun/faces/web-facesconfig_2_0.xsd" }, { "web-facesconfig_2_2.xsd", "/com/sun/faces/web-facesconfig_2_2.xsd" }, { "javaee_5.xsd", "/com/sun/faces/javaee_5.xsd" }, { "javaee_7.xsd", "/com/sun/faces/javaee_7.xsd" }, { "javaee_8.xsd", "/com/sun/faces/javaee_8.xsd" }, { "javaee_web_services_client_1_2.xsd", "/com/sun/faces/javaee_web_services_client_1_2.xsd" }, { "javaee_web_services_client_1_4.xsd", "/com/sun/faces/javaee_web_services_client_1_4.xsd" }, { "xml.xsd", "/com/sun/faces/xml.xsd" } }; /** * <p>Contains mapping between grammar name and the local URL to the * physical resource.</p> */ private HashMap<String, String> entities = new HashMap<String, String>(); // -------------------------------------------------------- Constructors public JsfEntityResolver() { // Add mappings between last segment of system ID and // the expected local physical resource. If the resource // cannot be found, then rely on default entity resolution // and hope a firewall isn't in the way or a proxy has // been configured for (String[] aDTD_SCHEMA_INFO : DTD_SCHEMA_INFO) { URL url = this.getClass().getResource(aDTD_SCHEMA_INFO[1]); if (url == null) { if (logger.isLoggable(Level.WARNING)) { logger.log(Level.WARNING, "Unable to locate local resource '" + aDTD_SCHEMA_INFO[1] + "'. Standard entity " + "resolution will be used when request " + "is present for '" + aDTD_SCHEMA_INFO[0] + '\''); } } else { entities.put(aDTD_SCHEMA_INFO[0], url.toString()); } } } // END JsfEntityResolver private VersionListener versionListener; public void setVersionListener(VersionListener listener) { versionListener = listener; } public VersionListener getVersionListener() { return versionListener; } // ----------------------------------------- Methods from DefaultHandler /** * <p>Resolves the physical resource using the last segment of * the <code>systemId</code> * (e.g. http://java.sun.com/dtds/web-facesconfig_1_1.dtd, * the last segment would be web-facesconfig_1_1.dtd). If a mapping * cannot be found for the segment, then defer to the * <code>DefaultHandler</code> for resolution.</p> */ public InputSource resolveEntity(String publicId, String systemId) throws SAXException { // publicId is ignored. Resolution performed using // the systemId. // If no system ID, defer to superclass if (systemId == null) { InputSource result; try { result = super.resolveEntity(publicId, systemId); } catch (Exception e) { throw new SAXException(e); } return result; } String grammarName = systemId.substring(systemId.lastIndexOf('/') + 1); if (null != getVersionListener()) { getVersionListener().takeActionOnGrammar(grammarName); } String entityURL = entities.get(grammarName); InputSource source; if (entityURL == null) { // we don't have a registered mapping, so defer to our // superclass for resolution if (logger.isLoggable(Level.FINE)) { logger.log(Level.FINE, "Unknown entity, deferring to superclass."); } try { source = super.resolveEntity(publicId, systemId); } catch (Exception e) { throw new SAXException(e); } } else { try { source = new InputSource(new URL(entityURL).openStream()); } catch (Exception e) { if (logger.isLoggable(Level.WARNING)) { logger.log(Level.WARNING, "Unable to create InputSource for URL '" + entityURL + "'"); } source = null; } } // Set the System ID of the InputSource with the URL of the local // resource - necessary to prevent parsing errors if (source != null) { source.setSystemId(entityURL); if (publicId != null) { source.setPublicId(publicId); } } return source; } // END resolveEntity } // END JsfEntityResolver private static class JsfErrorHandler implements ErrorHandler { public void warning(SAXParseException exception) throws SAXException { // do nothing } public void error(SAXParseException exception) throws SAXException { throw exception; } public void fatalError(SAXParseException exception) throws SAXException { throw exception; } } }