Guest access auto-login for JBoss Portal

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@2285 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/web/app/servlet/FacesHelper.java

@@ -0,0 +1,81 @@
+/*
+ * 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.servlet;
+
+import javax.faces.FactoryFinder;
+import javax.faces.component.UIViewRoot;
+import javax.faces.context.FacesContext;
+import javax.faces.context.FacesContextFactory;
+import javax.faces.lifecycle.Lifecycle;
+import javax.faces.lifecycle.LifecycleFactory;
+
+/**
+ * @author Kevin Roast
+ */
+public final class FacesHelper
+{
+   /**
+    * Private constructor
+    */
+   private FacesHelper()
+   {
+   }
+   
+   /**
+    * Return a valid FacesContext for the specific context, request and response.
+    * The FacesContext can be constructor for Servlet and Portlet use.
+    * 
+    * @param context       ServletContext or PortletContext
+    * @param request       ServletRequest or PortletRequest
+    * @param response      ServletReponse or PortletResponse
+    * 
+    * @return FacesContext
+    */
+   public static FacesContext getFacesContext(Object context, Object request, Object response)
+   {
+      FacesContext facesContext = FacesContext.getCurrentInstance();
+      if (facesContext != null) return facesContext;
+      
+      FacesContextFactory contextFactory = (FacesContextFactory)FactoryFinder.getFactory(FactoryFinder.FACES_CONTEXT_FACTORY);
+      LifecycleFactory lifecycleFactory = (LifecycleFactory)FactoryFinder.getFactory(FactoryFinder.LIFECYCLE_FACTORY);
+      Lifecycle lifecycle = lifecycleFactory.getLifecycle(LifecycleFactory.DEFAULT_LIFECYCLE);
+      
+      // Doesn't set this instance as the current instance of FacesContext.getCurrentInstance
+      facesContext = contextFactory.getFacesContext(context, request, response, lifecycle);
+      
+      // Set using our inner class
+      InnerFacesContext.setFacesContextAsCurrent(facesContext);
+      
+      // set a new viewRoot, otherwise context.getViewRoot returns null
+      UIViewRoot view = facesContext.getApplication().getViewHandler().createView(facesContext, "/jsp/root");
+      facesContext.setViewRoot(view);
+      
+      return facesContext;
+   }
+   
+   /**
+    * We need an inner class to be able to call FacesContext.setCurrentInstance
+    * since it's a protected method
+    */
+   private abstract static class InnerFacesContext extends FacesContext
+   {
+      protected static void setFacesContextAsCurrent(FacesContext facesContext)
+      {
+         FacesContext.setCurrentInstance(facesContext);
+      }
+   }
+}