Moving to root below branch label

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@2005 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/web/app/context/IContextListener.java

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+/*
+ * Copyright (C) 2005 Alfresco, Inc.
+ *
+ * Licensed under the Mozilla Public License version 1.1 
+ * with a permitted attribution clause. You may obtain a
+ * copy of the License at
+ *
+ *   http://www.alfresco.org/legal/license.txt
+ *
+ * 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.alfresco.web.app.context;
+
+/**
+ * Interface used to allow Beans to register themselves as interested in UI context events.
+ * <p>
+ * Beans supporting this interface should be register against the UIContextService. Then Beans
+ * which wish to indicate that the UI should refresh itself i.e. dump all cached data and settings,
+ * call the UIContextService.notifyBeans() to inform all registered instances of the change. 
+ * 
+ * @author Kevin Roast
+ */
+public interface IContextListener
+{
+   /**
+    * Method called by UIContextService.notifyBeans() to inform all registered beans that
+    * all UI Beans should refresh dump all cached data and settings. 
+    */
+   public void contextUpdated();
+}

source/java/org/alfresco/web/app/context/UIContextService.java

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+/*
+ * Copyright (C) 2005 Alfresco, Inc.
+ *
+ * Licensed under the Mozilla Public License version 1.1 
+ * with a permitted attribution clause. You may obtain a
+ * copy of the License at
+ *
+ *   http://www.alfresco.org/legal/license.txt
+ *
+ * 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.alfresco.web.app.context;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import javax.faces.context.FacesContext;
+
+/**
+ * Beans supporting the IContextListener interface are registered against this class. Then Beans
+ * which wish to indicate that the UI should refresh itself i.e. dump all cached data and settings,
+ * call the UIContextService.notifyBeans() to inform all registered instances of the change. 
+ * 
+ * @author Kevin Roast
+ */
+public final class UIContextService
+{
+   /**
+    * Private constructor
+    */
+   private UIContextService()
+   {
+   }
+   
+   /**
+    * Returns a Session local instance of the UIContextService
+    * 
+    * @return UIContextService for this Thread
+    */
+   public static UIContextService getInstance(FacesContext fc)
+   {
+      Map session = fc.getExternalContext().getSessionMap();
+      UIContextService service = (UIContextService)session.get(CONTEXT_KEY);
+      if (service == null)
+      {
+         service = new UIContextService();
+         session.put(CONTEXT_KEY, service);
+      }
+      
+      return service;
+   }
+   
+   /**
+    * Register a bean to be informed of context events
+    * 
+    * @param bean    Conforming to the IContextListener interface
+    */
+   public void registerBean(IContextListener bean)
+   {
+      if (bean == null)
+      {
+         throw new IllegalArgumentException("Bean reference specified cannot be null!");
+      }
+      
+      this.registeredBeans.put(bean.getClass(), bean);
+   }
+   
+   /**
+    * Remove a bean reference from those notified of changes
+    * 
+    * @param bean    Conforming to the IContextListener interface
+    */
+   public void unregisterBean(IContextListener bean)
+   {
+      if (bean == null)
+      {
+         throw new IllegalArgumentException("Bean reference specified cannot be null!");
+      }
+      
+      this.registeredBeans.remove(bean);
+   }
+   
+   /**
+    * Call to notify all register beans that the UI context has changed and they should
+    * refresh themselves as appropriate.
+    */
+   public void notifyBeans()
+   {
+      for (IContextListener listener: this.registeredBeans.values())
+      {
+         listener.contextUpdated();
+      }
+   }
+   
+   
+   /** key for the UI context service in the session */
+   private final static String CONTEXT_KEY = "__uiContextService";
+   
+   /** Map of bean registered against the context service */
+   private Map<Class, IContextListener> registeredBeans = new HashMap<Class, IContextListener>(7, 1.0f);
+}