/*
* Copyright 2005 Joe Walker
*
* Licensed 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.directwebremoting.faces;
import java.io.IOException;
import javax.faces.FactoryFinder;
import javax.faces.context.FacesContext;
import javax.faces.context.FacesContextFactory;
import javax.faces.lifecycle.Lifecycle;
import javax.faces.lifecycle.LifecycleFactory;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.logging.Log;
/**
* Filter integration for DWR framework. This filter was inspired by this
* article: http://www.thoughtsabout.net/blog/archives/000033.html
* @author Pierpaolo Follia (Latest revision: $Author: esa50833 $)
* @author Joe Walker [joe at getahead dot ltd dot uk]
* @noinspection AbstractClassNeverImplemented
*/
public class FacesExtensionFilter implements Filter
{
/* (non-Javadoc)
* @see javax.servlet.Filter#init(javax.servlet.FilterConfig)
*/
public void init(FilterConfig config) throws ServletException
{
servletContext = config.getServletContext();
}
/* (non-Javadoc)
* @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)
*/
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException
{
FacesContextFactory contextFactory = (FacesContextFactory) FactoryFinder.getFactory(FactoryFinder.FACES_CONTEXT_FACTORY);
LifecycleFactory lifecycleFactory = (LifecycleFactory) FactoryFinder.getFactory(FactoryFinder.LIFECYCLE_FACTORY);
Lifecycle lifecycle = lifecycleFactory.getLifecycle(LifecycleFactory.DEFAULT_LIFECYCLE);
// Either set a private member
// servletContext = filterConfig.getServletContext();
// in your filter init() method or set it here like this:
// ServletContext servletContext =
// ((HttpServletRequest) request).getSession().getServletContext();
// Note that the above line would fail if you are using any other
// protocol than http
// Doesn't set this instance as the current instance of
// FacesContext.getCurrentInstance
FacesContext facesContext = contextFactory.getFacesContext(servletContext, request, response, lifecycle);
// Set using our inner class
InnerFacesContext.setFacesContextAsCurrentInstance(facesContext);
try
{
// call the filter chain
chain.doFilter(request, response);
}
finally
{
// Clean up after ourselves as FacesContext is a ThreadLocal object
try
{
facesContext.release();
}
catch (IllegalStateException ex)
{
// Perhaps the FacesContext has already been released?
log.warn("Double release of faces context?", ex);
}
}
}
/* (non-Javadoc)
* @see javax.servlet.Filter#destroy()
*/
public void destroy()
{
}
// You 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 setFacesContextAsCurrentInstance(FacesContext facesContext)
{
FacesContext.setCurrentInstance(facesContext);
}
}
/**
* The servlet context
*/
private ServletContext servletContext = null;
/**
* The log stream
*/
private static final Log log = LogFactory.getLog(FacesExtensionFilter.class);
}