struts-sandbox/tiles-original/core-library/src/java/org/apache/util/PropertyMessageResources.java - struts-archive - Git at Google

 /*
  * Copyright 2004-2005 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.util;

 import java.io.IOException;
 import java.io.InputStream;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Locale;
 import java.util.Properties;

 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;

 /**
  * Concrete subclass of <code>MessageResources</code> that reads message keys
  * and corresponding strings from named property resources in the same manner
  * that <code>java.util.PropertyResourceBundle</code> does.  The
  * <code>base</code> property defines the base property resource name, and
  * must be specified.
  * <p>
  * <strong>IMPLEMENTATION NOTE</strong> - This class trades memory for
  * speed by caching all messages located via generalizing the Locale under
  * the original locale as well.
  * This results in specific messages being stored in the message cache
  * more than once, but improves response time on subsequent requests for
  * the same locale + key combination.
  *
  * @author Craig R. McClanahan
  * @author David Graham
  * @version $Revision: 1.8 $ $Date: 2003/04/19 19:06:02 $
  */
 public class PropertyMessageResources extends MessageResources {


     // ----------------------------------------------------------- Constructors


     /**
      * Construct a new PropertyMessageResources according to the
      * specified parameters.
      *
      * @param factory The MessageResourcesFactory that created us
      * @param config The configuration parameter for this MessageResources
      */
     public PropertyMessageResources(MessageResourcesFactory factory,
                                     String config) {

         super(factory, config);
         log.info("Initializing, config='" + config + "'");

     }


     /**
      * Construct a new PropertyMessageResources according to the
      * specified parameters.
      *
      * @param factory The MessageResourcesFactory that created us
      * @param config The configuration parameter for this MessageResources
      * @param returnNull The returnNull property we should initialize with
      */
     public PropertyMessageResources(MessageResourcesFactory factory,
                                     String config, boolean returnNull) {

         super(factory, config, returnNull);
         log.info("Initializing, config='" + config +
                  "', returnNull=" + returnNull);

     }


     // ------------------------------------------------------------- Properties


     /**
      * The set of locale keys for which we have already loaded messages, keyed
      * by the value calculated in <code>localeKey()</code>.
      */
     protected HashMap locales = new HashMap();


     /**
      * The <code>Log</code> instance for this class.
      */
     protected static final Log log =
         LogFactory.getLog(PropertyMessageResources.class);


     /**
      * The cache of messages we have accumulated over time, keyed by the
      * value calculated in <code>messageKey()</code>.
      */
     protected HashMap messages = new HashMap();


     // --------------------------------------------------------- Public Methods


     /**
      * Returns a text message for the specified key, for the default Locale.
      * A null string result will be returned by this method if no relevant
      * message resource is found for this key or Locale, if the
      * <code>returnNull</code> property is set.  Otherwise, an appropriate
      * error message will be returned.
      * <p>
      * This method must be implemented by a concrete subclass.
      *
      * @param locale The requested message Locale, or <code>null</code>
      *  for the system default Locale
      * @param key The message key to look up
      * @return text message for the specified key and locale
      */
     public String getMessage(Locale locale, String key) {

         if (log.isDebugEnabled()) {
             log.debug("getMessage(" + locale + "," + key + ")");
         }

         // Initialize variables we will require
         String localeKey = localeKey(locale);
         String originalKey = messageKey(localeKey, key);
         String messageKey = null;
         String message = null;
         int underscore = 0;
         boolean addIt = false;  // Add if not found under the original key

         // Loop from specific to general Locales looking for this message
         while (true) {

             // Load this Locale's messages if we have not done so yet
             loadLocale(localeKey);

             // Check if we have this key for the current locale key
             messageKey = messageKey(localeKey, key);
             synchronized (messages) {
                 message = (String) messages.get(messageKey);
                 if (message != null) {
                     if (addIt) {
                         messages.put(originalKey, message);
                     }
                     return (message);
                 }
             }

             // Strip trailing modifiers to try a more general locale key
             addIt = true;
             underscore = localeKey.lastIndexOf("_");
             if (underscore < 0) {
                 break;
             }
             localeKey = localeKey.substring(0, underscore);

         }

         // Try the default locale if the current locale is different
         if (!defaultLocale.equals(locale)) {
             localeKey = localeKey(defaultLocale);
             messageKey = messageKey(localeKey, key);
             loadLocale(localeKey);
             synchronized (messages) {
                 message = (String) messages.get(messageKey);
                 if (message != null) {
                     messages.put(originalKey, message);
                     return (message);
                 }
             }
         }

         // As a last resort, try the default Locale
         localeKey = "";
         messageKey = messageKey(localeKey, key);
         loadLocale(localeKey);
         synchronized (messages) {
             message = (String) messages.get(messageKey);
             if (message != null) {
                 messages.put(originalKey, message);
                 return (message);
             }
         }

         // Return an appropriate error indication
         if (returnNull) {
             return (null);
         } else {
             return ("???" + messageKey(locale, key) + "???");
         }

     }


     // ------------------------------------------------------ Protected Methods


     /**
      * Load the messages associated with the specified Locale key.  For this
      * implementation, the <code>config</code> property should contain a fully
      * qualified package and resource name, separated by periods, of a series
      * of property resources to be loaded from the class loader that created
      * this PropertyMessageResources instance.  This is exactly the same name
      * format you would use when utilizing the
      * <code>java.util.PropertyResourceBundle</code> class.
      *
      * @param localeKey Locale key for the messages to be retrieved
      */
     protected synchronized void loadLocale(String localeKey) {

         if (log.isTraceEnabled()) {
             log.trace("loadLocale(" + localeKey + ")");
         }

         // Have we already attempted to load messages for this locale?
         if (locales.get(localeKey) != null) {
             return;
         }
         locales.put(localeKey, localeKey);

         // Set up to load the property resource for this locale key, if we can
         String name = config.replace('.', '/');
         if (localeKey.length() > 0) {
             name += "_" + localeKey;
         }
         name += ".properties";
         InputStream is = null;
         Properties props = new Properties();

         // Load the specified property resource
         if (log.isTraceEnabled()) {
             log.trace("  Loading resource '" + name + "'");
         }

         ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
         if (classLoader == null) {
             classLoader = this.getClass().getClassLoader();
         }

         is = classLoader.getResourceAsStream(name);
         if (is != null) {
             try {
                 props.load(is);

             } catch (IOException e) {
                 log.error("loadLocale()", e);
             } finally {
                 try {
                     is.close();
                 } catch (IOException e) {
                     log.error("loadLocale()", e);
                 }
             }
         }

         if (log.isTraceEnabled()) {
             log.trace("  Loading resource completed");
         }

         // Copy the corresponding values into our cache
         if (props.size() < 1) {
             return;
         }

         synchronized (messages) {
             Iterator names = props.keySet().iterator();
             while (names.hasNext()) {
                 String key = (String) names.next();
                 if (log.isTraceEnabled()) {
                     log.trace("  Saving message key '" + messageKey(localeKey, key));
                 }
                 messages.put(messageKey(localeKey, key), props.getProperty(key));
             }
         }

     }


 }
	/*
	* Copyright 2004-2005 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.util;

	import java.io.IOException;
	import java.io.InputStream;
	import java.util.HashMap;
	import java.util.Iterator;
	import java.util.Locale;
	import java.util.Properties;

	import org.apache.commons.logging.Log;
	import org.apache.commons.logging.LogFactory;

	/**
	* Concrete subclass of <code>MessageResources</code> that reads message keys
	* and corresponding strings from named property resources in the same manner
	* that <code>java.util.PropertyResourceBundle</code> does. The
	* <code>base</code> property defines the base property resource name, and
	* must be specified.
	* <p>
	* <strong>IMPLEMENTATION NOTE</strong> - This class trades memory for
	* speed by caching all messages located via generalizing the Locale under
	* the original locale as well.
	* This results in specific messages being stored in the message cache
	* more than once, but improves response time on subsequent requests for
	* the same locale + key combination.
	*
	* @author Craig R. McClanahan
	* @author David Graham
	* @version $Revision: 1.8 $ $Date: 2003/04/19 19:06:02 $
	*/
	public class PropertyMessageResources extends MessageResources {


	// ----------------------------------------------------------- Constructors


	/**
	* Construct a new PropertyMessageResources according to the
	* specified parameters.
	*
	* @param factory The MessageResourcesFactory that created us
	* @param config The configuration parameter for this MessageResources
	*/
	public PropertyMessageResources(MessageResourcesFactory factory,
	String config) {

	super(factory, config);
	log.info("Initializing, config='" + config + "'");

	}


	/**
	* Construct a new PropertyMessageResources according to the
	* specified parameters.
	*
	* @param factory The MessageResourcesFactory that created us
	* @param config The configuration parameter for this MessageResources
	* @param returnNull The returnNull property we should initialize with
	*/
	public PropertyMessageResources(MessageResourcesFactory factory,
	String config, boolean returnNull) {

	super(factory, config, returnNull);
	log.info("Initializing, config='" + config +
	"', returnNull=" + returnNull);

	}


	// ------------------------------------------------------------- Properties


	/**
	* The set of locale keys for which we have already loaded messages, keyed
	* by the value calculated in <code>localeKey()</code>.
	*/
	protected HashMap locales = new HashMap();


	/**
	* The <code>Log</code> instance for this class.
	*/
	protected static final Log log =
	LogFactory.getLog(PropertyMessageResources.class);


	/**
	* The cache of messages we have accumulated over time, keyed by the
	* value calculated in <code>messageKey()</code>.
	*/
	protected HashMap messages = new HashMap();


	// --------------------------------------------------------- Public Methods


	/**
	* Returns a text message for the specified key, for the default Locale.
	* A null string result will be returned by this method if no relevant
	* message resource is found for this key or Locale, if the
	* <code>returnNull</code> property is set. Otherwise, an appropriate
	* error message will be returned.
	* <p>
	* This method must be implemented by a concrete subclass.
	*
	* @param locale The requested message Locale, or <code>null</code>
	* for the system default Locale
	* @param key The message key to look up
	* @return text message for the specified key and locale
	*/
	public String getMessage(Locale locale, String key) {

	if (log.isDebugEnabled()) {
	log.debug("getMessage(" + locale + "," + key + ")");
	}

	// Initialize variables we will require
	String localeKey = localeKey(locale);
	String originalKey = messageKey(localeKey, key);
	String messageKey = null;
	String message = null;
	int underscore = 0;
	boolean addIt = false; // Add if not found under the original key

	// Loop from specific to general Locales looking for this message
	while (true) {

	// Load this Locale's messages if we have not done so yet
	loadLocale(localeKey);

	// Check if we have this key for the current locale key
	messageKey = messageKey(localeKey, key);
	synchronized (messages) {
	message = (String) messages.get(messageKey);
	if (message != null) {
	if (addIt) {
	messages.put(originalKey, message);
	}
	return (message);
	}
	}

	// Strip trailing modifiers to try a more general locale key
	addIt = true;
	underscore = localeKey.lastIndexOf("_");
	if (underscore < 0) {
	break;
	}
	localeKey = localeKey.substring(0, underscore);

	}

	// Try the default locale if the current locale is different
	if (!defaultLocale.equals(locale)) {
	localeKey = localeKey(defaultLocale);
	messageKey = messageKey(localeKey, key);
	loadLocale(localeKey);
	synchronized (messages) {
	message = (String) messages.get(messageKey);
	if (message != null) {
	messages.put(originalKey, message);
	return (message);
	}
	}
	}

	// As a last resort, try the default Locale
	localeKey = "";
	messageKey = messageKey(localeKey, key);
	loadLocale(localeKey);
	synchronized (messages) {
	message = (String) messages.get(messageKey);
	if (message != null) {
	messages.put(originalKey, message);
	return (message);
	}
	}

	// Return an appropriate error indication
	if (returnNull) {
	return (null);
	} else {
	return ("???" + messageKey(locale, key) + "???");
	}

	}


	// ------------------------------------------------------ Protected Methods


	/**
	* Load the messages associated with the specified Locale key. For this
	* implementation, the <code>config</code> property should contain a fully
	* qualified package and resource name, separated by periods, of a series
	* of property resources to be loaded from the class loader that created
	* this PropertyMessageResources instance. This is exactly the same name
	* format you would use when utilizing the
	* <code>java.util.PropertyResourceBundle</code> class.
	*
	* @param localeKey Locale key for the messages to be retrieved
	*/
	protected synchronized void loadLocale(String localeKey) {

	if (log.isTraceEnabled()) {
	log.trace("loadLocale(" + localeKey + ")");
	}

	// Have we already attempted to load messages for this locale?
	if (locales.get(localeKey) != null) {
	return;
	}
	locales.put(localeKey, localeKey);

	// Set up to load the property resource for this locale key, if we can
	String name = config.replace('.', '/');
	if (localeKey.length() > 0) {
	name += "_" + localeKey;
	}
	name += ".properties";
	InputStream is = null;
	Properties props = new Properties();

	// Load the specified property resource
	if (log.isTraceEnabled()) {
	log.trace(" Loading resource '" + name + "'");
	}

	ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
	if (classLoader == null) {
	classLoader = this.getClass().getClassLoader();
	}

	is = classLoader.getResourceAsStream(name);
	if (is != null) {
	try {
	props.load(is);

	} catch (IOException e) {
	log.error("loadLocale()", e);
	} finally {
	try {
	is.close();
	} catch (IOException e) {
	log.error("loadLocale()", e);
	}
	}
	}

	if (log.isTraceEnabled()) {
	log.trace(" Loading resource completed");
	}

	// Copy the corresponding values into our cache
	if (props.size() < 1) {
	return;
	}

	synchronized (messages) {
	Iterator names = props.keySet().iterator();
	while (names.hasNext()) {
	String key = (String) names.next();
	if (log.isTraceEnabled()) {
	log.trace(" Saving message key '" + messageKey(localeKey, key));
	}
	messages.put(messageKey(localeKey, key), props.getProperty(key));
	}
	}

	}


	}