/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.myfaces.shared.view;
import javax.faces.application.Application;
import javax.faces.application.ViewHandler;
import javax.faces.component.UIViewRoot;
import javax.faces.context.FacesContext;
import javax.faces.view.ViewDeclarationLanguage;
import org.apache.myfaces.shared.application.InvalidViewIdException;
/**
* @author Simon Lessard (latest modification by $Author: bommel $)
* @version $Revision: 1187701 $ $Date: 2011-10-22 12:21:54 +0000 (Sat, 22 Oct 2011) $
*
* @since 2.0
*/
public abstract class ViewDeclarationLanguageBase extends ViewDeclarationLanguage
{
/**
* Process the specification required algorithm that is generic to all PDL.
*
* @param context
* @param viewId
*/
public UIViewRoot createView(FacesContext context, String viewId)
{
checkNull(context, "context");
//checkNull(viewId, "viewId");
try
{
viewId = calculateViewId(context, viewId);
Application application = context.getApplication();
// Create a new UIViewRoot object instance using Application.createComponent(UIViewRoot.COMPONENT_TYPE).
UIViewRoot newViewRoot = (UIViewRoot) application.createComponent(UIViewRoot.COMPONENT_TYPE);
UIViewRoot oldViewRoot = context.getViewRoot();
if (oldViewRoot == null)
{
// If not, this method must call calculateLocale() and calculateRenderKitId(), and store the results
// as the values of the locale and renderKitId, proeprties, respectively, of the newly created
// UIViewRoot.
ViewHandler handler = application.getViewHandler();
newViewRoot.setLocale(handler.calculateLocale(context));
newViewRoot.setRenderKitId(handler.calculateRenderKitId(context));
}
else
{
// If there is an existing UIViewRoot available on the FacesContext, this method must copy its locale
// and renderKitId to this new view root
newViewRoot.setLocale(oldViewRoot.getLocale());
newViewRoot.setRenderKitId(oldViewRoot.getRenderKitId());
}
// TODO: VALIDATE - The spec is silent on the following line, but I feel bad if I don't set it
newViewRoot.setViewId(viewId);
return newViewRoot;
}
catch (InvalidViewIdException e)
{
// If no viewId could be identified, or the viewId is exactly equal to the servlet mapping,
// send the response error code SC_NOT_FOUND with a suitable message to the client.
sendSourceNotFound(context, e.getMessage());
// TODO: VALIDATE - Spec is silent on the return value when an error was sent
return null;
}
}
/**
* {@inheritDoc}
*/
@Override
public UIViewRoot restoreView(FacesContext context, String viewId)
{
checkNull(context, "context");
//checkNull(viewId, "viewId");
Application application = context.getApplication();
ViewHandler applicationViewHandler = application.getViewHandler();
String renderKitId = applicationViewHandler.calculateRenderKitId(context);
UIViewRoot viewRoot = application.getStateManager().restoreView(context, viewId, renderKitId);
return viewRoot;
}
/**
* Calculates the effective view identifier for the specified raw view identifier.
*
* @param context le current FacesContext
* @param viewId the raw view identifier
*
* @return the effective view identifier
*/
protected abstract String calculateViewId(FacesContext context, String viewId);
/**
* Send a source not found to the client. Although it can be considered ok in JSP mode,
* I think it's pretty lame to have this kind of requirement at VDL level considering VDL
* represents the page --> JSF tree link, not the transport layer required to send a
* SC_NOT_FOUND.
*
* @param context le current FacesContext
* @param message the message associated with the error
*/
protected abstract void sendSourceNotFound(FacesContext context, String message);
/**
* Check if the specified value of a param is <code>null</code>.
*
* @param o the parameter's value
* @param param the parameter's name
*
* @throws NullPointerException if the value is <code>null</code>
*/
protected void checkNull(final Object o, final String param)
{
if (o == null)
{
throw new NullPointerException(param + " can not be null.");
}
}
}