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/* * $Id: ChannelFactorySet.java 54929 2004-10-16 16:38:42Z germuska $ * * Copyright 1999-2004 The Apache Software Foundation. * * 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.apache.struts.webapp.tiles.channel; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.util.HashMap; import java.util.Map; import javax.servlet.ServletContext; import javax.servlet.ServletRequest; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.struts.tiles.DefinitionsFactoryException; import org.apache.struts.tiles.FactoryNotFoundException; import org.apache.struts.tiles.xmlDefinition.DefinitionsFactory; import org.apache.struts.tiles.xmlDefinition.FactorySet; import org.apache.struts.tiles.xmlDefinition.XmlDefinitionsSet; import org.apache.struts.tiles.xmlDefinition.XmlParser; import org.xml.sax.SAXException; /** * Component Definitions factory. * This implementation of Component Definitions factory allows i18n * Component definitions factory allowing i18n definition. * A definition is retrieved by its name, and using locale setted in appropriate * session context. Definitions are defined in different files, one for each locale. * A definition file is loaded using common name extended with locale code * (ex : templateDefinitions_fr.xml). If no file is found under this name, use default * file. */ public class ChannelFactorySet extends FactorySet { private static final Log log = LogFactory.getLog(ChannelFactorySet.class); /** * Debug flag. * @deprecated This will be removed in a release after Struts 1.2. */ public static final boolean debug = false; /** * Default name. */ public static final String DEFAULT_DEFINITIONS_FILE_NAME = "/WEB-INF/templateDefinitions.xml"; /** * Config file parameter name. */ public static final String DEFINITIONS_CONFIG_PARAMETER_NAME = "definitions-config"; /** * Config file parameter name. */ public static final String FACTORY_SELECTOR_KEY = "ChannelFactorySet.factorySelectorKey"; /** * Default filenames extension. */ public static final String FILENAME_EXTENSION = ".xml"; /** * Default factory. */ protected DefinitionsFactory defaultFactory = null; /** * Xml parser used. */ protected XmlParser xmlParser = null; /** * Names of default file containing definition descriptions. */ private String filename = null; /** * Collection of already loaded definitions set, referenced by their suffix. */ private Map loaded = null; /** * Parameterless Constructor. * Method initFactory must be called prior to any use of created factory. */ public ChannelFactorySet() { super(); } /** * Constructor. * Init the factory by reading appropriate configuration file. * @throws FactoryNotFoundException Can't find factory configuration file. */ public ChannelFactorySet(ServletContext servletContext, Map properties) throws DefinitionsFactoryException { initFactory(servletContext, properties); } /** * Initialization method. * Init the factory by reading appropriate configuration file. * This method is called exactly once immediately after factory creation in * case of internal creation (by DefinitionUtil). * @param servletContext Servlet Context passed to newly created factory. * @param properties Map of name/property passed to newly created factory. Map can contains * more properties than requested. * @throws DefinitionsFactoryException An error occur during initialization. */ public void initFactory(ServletContext servletContext, Map properties) throws DefinitionsFactoryException { // read properties values String proposedFilename = (String) properties.get(DEFINITIONS_CONFIG_PARAMETER_NAME); // Compute filenames to use boolean isFileSpecified = true; if (proposedFilename == null) { proposedFilename = DEFAULT_DEFINITIONS_FILE_NAME; isFileSpecified = false; } try { initFactory(servletContext, proposedFilename); return; } catch (FileNotFoundException ex) { // If a filename is specified, throw appropriate error. if (isFileSpecified) { throw new FactoryNotFoundException( ex.getMessage() + " : Can't find file '" + proposedFilename + "'"); } } } /** * Initialization method. * Init the factory by reading appropriate configuration file. * This method is called exactly once immediately after factory creation in * case of internal creation (by DefinitionUtil). * @param servletContext Servlet Context passed to newly created factory. * @param proposedFilename File names, comma separated, to use as base file names. * @throws DefinitionsFactoryException An error occur during initialization. */ protected void initFactory(ServletContext servletContext, String proposedFilename) throws DefinitionsFactoryException, FileNotFoundException { filename = proposedFilename; loaded = new HashMap(); defaultFactory = createDefaultFactory(servletContext); } /** * Get default factory. * @return Default factory */ protected DefinitionsFactory getDefaultFactory() { return defaultFactory; } /** * Create default factory . * @param servletContext Current servlet context. Used to open file. * @return Created default definition factory. * @throws DefinitionsFactoryException If an error occur while creating factory. * @throws FileNotFoundException if factory can't be loaded from filenames. */ protected DefinitionsFactory createDefaultFactory(ServletContext servletContext) throws DefinitionsFactoryException, FileNotFoundException { XmlDefinitionsSet rootXmlConfig = parseXmlKeyFile(servletContext, "", null); if (rootXmlConfig == null) { throw new FileNotFoundException(); } rootXmlConfig.resolveInheritances(); return new DefinitionsFactory(rootXmlConfig); } /** * Extract key that will be used to get the sub factory. * @param name Name of requested definition * @param request Current servlet request. * @param servletContext Current servlet context * @return the key or null if not found. * @roseuid 3AF6F887018A */ protected Object getDefinitionsFactoryKey(String name, ServletRequest request, ServletContext servletContext) { Object key = null; HttpSession session = ((HttpServletRequest) request).getSession(false); if (session != null) { key = session.getAttribute(FACTORY_SELECTOR_KEY); } return key; } /** * Create a factory for specified key. * If creation failed, return default factory, and output an error message in * console. * @param key * @return Definition factory for specified key. * @throws DefinitionsFactoryException If an error occur while creating factory. */ protected DefinitionsFactory createFactory(Object key, ServletRequest request, ServletContext servletContext) throws DefinitionsFactoryException { if (key == null) { return getDefaultFactory(); } // Already loaded ? DefinitionsFactory factory = (DefinitionsFactory) loaded.get(key); if (factory != null) { // yes, stop loading return factory; } // Try to load file associated to key. If fail, stop and return default factory. XmlDefinitionsSet lastXmlFile = parseXmlKeyFile(servletContext, "_" + (String) key, null); if (lastXmlFile == null) { log.warn("No definition factory associated to key '" + key + "'. Use default factory instead."); factory = getDefaultFactory(); loaded.put(key, factory); return factory; } // Parse default file, and add key file. XmlDefinitionsSet rootXmlConfig = parseXmlKeyFile(servletContext, "", null); rootXmlConfig.extend(lastXmlFile); rootXmlConfig.resolveInheritances(); factory = new DefinitionsFactory(rootXmlConfig); loaded.put(key, factory); log.info(factory); // return last available found ! return factory; } /** * Parse files associated to postix if they exist. * For each name in filenames, append postfix before file extension, * then try to load the corresponding file. * If file doesn't exist, try next one. Each file description is added to * the XmlDefinitionsSet description. * The XmlDefinitionsSet description is created only if there is a definition file. * Inheritance is not resolved in the returned XmlDefinitionsSet. * If no description file can be opened, and no definiion set is provided, return null. * @param postfix Postfix to add to each description file. * @param xmlDefinitions Definitions set to which definitions will be added. If null, a definitions * set is created on request. * @return XmlDefinitionsSet The definitions set created or passed as parameter. * @throws DefinitionsFactoryException If an error happen during file parsing. */ private XmlDefinitionsSet parseXmlKeyFile(ServletContext servletContext, String postfix, XmlDefinitionsSet xmlDefinitions) throws DefinitionsFactoryException { if (postfix != null && postfix.length() == 0) postfix = null; String fullName = concatPostfix(filename, postfix); return parseXmlFile(servletContext, fullName, xmlDefinitions); } /** * Parse specified xml file and add definition to specified definitions set. * This method is used to load several description files in one instances list. * If filename exist and definition set is null, create a new set. Otherwise, return * passed definition set (can be null). * @param servletContext Current servlet context. Used to open file. * @param filename Name of file to parse. * @param xmlDefinitions Definitions set to which definitions will be added. If null, a definitions * set is created on request. * @return XmlDefinitionsSet The definitions set created or passed as parameter. * @throws DefinitionsFactoryException If an error happen during file parsing. */ private XmlDefinitionsSet parseXmlFile(ServletContext servletContext, String filename, XmlDefinitionsSet xmlDefinitions) throws DefinitionsFactoryException { try { log.debug("Trying to load '" + filename + "'."); InputStream input = servletContext.getResourceAsStream(filename); if (input == null) { return xmlDefinitions; } xmlParser = new XmlParser(); // Check if definition set already exist. if (xmlDefinitions == null) { xmlDefinitions = new XmlDefinitionsSet(); } xmlParser.parse(input, xmlDefinitions); } catch (SAXException ex) { log.debug("Error while parsing file '" + filename + "'.", ex); throw new DefinitionsFactoryException("Error while parsing file '" + filename + "'. " + ex.getMessage(), ex); } catch (IOException ex) { throw new DefinitionsFactoryException( "IO Error while parsing file '" + filename + "'. " + ex.getMessage(), ex); } return xmlDefinitions; } /** * Concat postfix to the name. Take care of existing filename extension. * Transform the given name "name.ext" to have "name" + "postfix" + "ext". * If there is no ext, return "name" + "postfix". */ private String concatPostfix(String name, String postfix) { if (postfix == null) { return name; } //postfix = "_" + postfix; // Search file name extension. // take care of Unix files starting with . int dotIndex = name.lastIndexOf("."); int lastNameStart = name.lastIndexOf(java.io.File.pathSeparator); if (dotIndex < 1 || dotIndex < lastNameStart) return name + postfix; String ext = name.substring(dotIndex); name = name.substring(0, dotIndex); return name + postfix + ext; } }