. Memory usage improvement:

- Web-client now caches ResourceBundle objects and shares them between all users.

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@2412 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/web/app/Application.java

@@ -33,7 +33,6 @@ import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpSession;
 
 import org.alfresco.config.ConfigService;
-import org.alfresco.error.AlfrescoRuntimeException;
 import org.alfresco.repo.importer.ImporterBootstrap;
 import org.alfresco.service.cmr.repository.StoreRef;
 import org.alfresco.web.app.servlet.AuthenticationHelper;
@@ -483,14 +482,7 @@ public class Application
          {
             locale = Locale.getDefault();
          }
-         bundle = ResourceBundle.getBundle(MESSAGE_BUNDLE, locale);
-         if (bundle == null)
-         {
-            throw new AlfrescoRuntimeException("Unable to load Alfresco messages bundle: " + MESSAGE_BUNDLE);
-         }
-         
-         // apply our wrapper to catch MissingResourceException
-         bundle = new ResourceBundleWrapper(bundle);
+         bundle = ResourceBundleWrapper.findSharedResourceBundle(MESSAGE_BUNDLE, locale);
          
          session.setAttribute(MESSAGE_BUNDLE, bundle);
       }
@@ -520,14 +512,7 @@ public class Application
          {
             locale = Locale.getDefault();
          }
-         bundle = ResourceBundle.getBundle(MESSAGE_BUNDLE, locale);
-         if (bundle == null)
-         {
-            throw new AlfrescoRuntimeException("Unable to load Alfresco messages bundle: " + MESSAGE_BUNDLE);
-         }
-         
-         // apply our wrapper to catch MissingResourceException
-         bundle = new ResourceBundleWrapper(bundle);
+         bundle = ResourceBundleWrapper.findSharedResourceBundle(MESSAGE_BUNDLE, locale);
          
          session.put(MESSAGE_BUNDLE, bundle);
       }

source/java/org/alfresco/web/app/ResourceBundleWrapper.java

@@ -17,28 +17,39 @@
 package org.alfresco.web.app;
 
 import java.util.Enumeration;
+import java.util.HashMap;
+import java.util.Locale;
+import java.util.Map;
 import java.util.MissingResourceException;
 import java.util.ResourceBundle;
+
+import org.alfresco.error.AlfrescoRuntimeException;
 import org.apache.log4j.Logger;
 import org.apache.log4j.Priority;
 
 /**
  * Wrapper around Alfresco Resource Bundle objects. Used to catch and handle missing
  * resource exception to help identify missing I18N strings in client apps.
+ * <p>
+ * Also provides a factory method to get/create a shared instance to a named resource
+ * bundle for a particular locale.
  * 
  * @author Kevin Roast
  */
 public final class ResourceBundleWrapper extends ResourceBundle
 {
    private static Logger logger = Logger.getLogger(ResourceBundleWrapper.class);
+   
    private ResourceBundle delegate;
    
+   private static Map<String, ResourceBundle> cache = new HashMap<String, ResourceBundle>();  
+   
    /**
     * Constructor
     * 
     * @param bundle     The ResourceBundle to route calls too
     */
-   public ResourceBundleWrapper(ResourceBundle bundle)
+   private ResourceBundleWrapper(ResourceBundle bundle)
    {
       this.delegate = bundle;
    }
@@ -68,4 +79,42 @@ public final class ResourceBundleWrapper extends ResourceBundle
          return "$$" + key + "$$";
       }
    }
+   
+   /**
+    * Factory method to get/create a shared instance to a named resource bundle for a
+    * particular locale. A static cache of language bundles is used to save memory, as each
+    * bundle consumes >300K per user and they are read only objects.
+    * 
+    * @param name       Bundle name
+    * @param locale     Locale to retrieve bundle for
+    * 
+    * @return Shared ResourceBundle instance for specified locale
+    */
+   public static ResourceBundle findSharedResourceBundle(String name, Locale locale)
+   {
+      String key = name + '_' + locale;
+      
+      ResourceBundle bundle = cache.get(key);
+      if (bundle == null)
+      {
+         // we can safely use a weak synchronization point here - i.e. it doesn't actually matter
+         // if more than one thread loads and caches the same bundle if a race condition occurs
+         synchronized (cache)
+         {
+            bundle = ResourceBundle.getBundle(name, locale);
+            if (bundle == null)
+            {
+               throw new AlfrescoRuntimeException("Unable to load Alfresco messages bundle: " + name);
+            }
+            
+            // apply our wrapper to catch MissingResourceException
+            bundle = new ResourceBundleWrapper(bundle);
+            
+            // cache the bundle for later use
+            cache.put(key, bundle);
+         }
+      }
+      
+      return bundle;
+   }
 }