- Introduction of the component generator framework

- Changed some confg attrbiute names for consistency

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@2634 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

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

@@ -17,6 +17,7 @@
 package org.alfresco.web.app.servlet;
 
 import javax.faces.FactoryFinder;
+import javax.faces.component.UIComponent;
 import javax.faces.component.UIViewRoot;
 import javax.faces.context.FacesContext;
 import javax.faces.context.FacesContextFactory;
@@ -30,11 +31,19 @@ import javax.servlet.ServletContext;
 import javax.servlet.ServletRequest;
 import javax.servlet.ServletResponse;
 
+import org.alfresco.error.AlfrescoRuntimeException;
+import org.alfresco.web.bean.generator.IComponentGenerator;
+import org.alfresco.web.ui.repo.RepoConstants;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
 /**
  * @author Kevin Roast
  */
 public final class FacesHelper
 {
+   private static Log logger = LogFactory.getLog(FacesHelper.class);
+   
    /**
     * Private constructor
     */
@@ -118,6 +127,91 @@ public final class FacesHelper
       return vb.getValue(fc);
    }
    
+   /**
+    * Sets up the id for the given component, if the id is null a unique one
+    * is generated using the standard Faces algorithm. If an id is present it
+    * is checked for illegal characters.
+    * 
+    * @param context FacesContext
+    * @param component The component to set the id for
+    * @param id The id to set
+    */
+   public static void setupComponentId(FacesContext context, UIComponent component, String id)
+   {
+      if (id == null)
+      {
+         id = context.getViewRoot().createUniqueId();
+      }
+      else
+      {
+         // make sure we do not have illegal characters in the id
+         id = id.replace(':', '_');
+         
+         // TODO: check all other illegal characters - only allowed dash and underscore
+      }
+      
+      component.setId(id);
+   }
+   
+   /**
+    * Retrieves the named component generator implementation.
+    * If the named generator is not found the TextFieldGenerator is looked up
+    * as a default, if this is also not found an AlfrescoRuntimeException is thrown.
+    * 
+    * @param context FacesContext
+    * @param generator The name of the component generator to retrieve
+    * @return The component generator instance
+    */
+   public static IComponentGenerator getComponentGenerator(FacesContext context, String generatorName)
+   {
+      IComponentGenerator generator = lookupComponentGenerator(context, generatorName);
+      
+      if (generator == null)
+      {
+         // create a text field if we can't find a component generator (a warning should have already been
+         // displayed on the appserver console)
+         
+         logger.warn("Attempting to find default component generator '" + RepoConstants.GENERATOR_TEXT_FIELD + "'");
+         generator = lookupComponentGenerator(context, RepoConstants.GENERATOR_TEXT_FIELD);
+      }
+      
+      // if we still don't have a component generator we should abort as vital configuration is missing
+      if (generator == null)
+      {
+         throw new AlfrescoRuntimeException("Failed to find a component generator, please ensure the '" +
+               RepoConstants.GENERATOR_TEXT_FIELD + "' bean is present in your configuration");
+      }
+      
+      return generator;
+   }
+   
+   private static IComponentGenerator lookupComponentGenerator(FacesContext context, String generatorName)
+   {
+      IComponentGenerator generator = null;
+      
+      Object obj = FacesHelper.getManagedBean(context, generatorName);
+      if (obj != null)
+      {
+         if (obj instanceof IComponentGenerator)
+         {
+            generator = (IComponentGenerator)obj;
+            
+            if (logger.isDebugEnabled())
+               logger.debug("Found component generator for '" + generatorName + "': " + generator);
+         }
+         else
+         {
+            logger.warn("Bean '" + generatorName + "' does not implement IComponentGenerator");
+         }
+      }
+      else
+      {
+         logger.warn("Failed to find component generator with name of '" + generatorName + "'");
+      }
+      
+      return generator;
+   }
+   
    /**
     * We need an inner class to be able to call FacesContext.setCurrentInstance
     * since it's a protected method