struts-sandbox/tiles-documentation/src/java/org/apache/struts/webapp/tiles/channel/ChannelFactorySet.java - struts-archive - Git at Google

 /*
  * $Id$
  *
  * 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);

     /**
      * 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;
     }

 }
	/*
	* $Id$
	*
	* 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);

	/**
	* 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;
	}

	}