/******************************************************************************
* JBoss, a division of Red Hat *
* Copyright 2006, Red Hat Middleware, LLC, and individual *
* contributors as indicated by the @authors tag. See the *
* copyright.txt in the distribution for a full listing of *
* individual contributors. *
* *
* This is free software; you can redistribute it and/or modify it *
* under the terms of the GNU Lesser General Public License as *
* published by the Free Software Foundation; either version 2.1 of *
* the License, or (at your option) any later version. *
* *
* This software is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU *
* Lesser General Public License for more details. *
* *
* You should have received a copy of the GNU Lesser General Public *
* License along with this software; if not, write to the Free *
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA *
* 02110-1301 USA, or see the FSF site: http://www.fsf.org. *
******************************************************************************/
package org.gatein.common.mc.bootstrap;
import org.jboss.kernel.plugins.deployment.xml.BeanXMLDeployer;
import org.jboss.kernel.spi.deployment.KernelDeployment;
import org.jboss.kernel.spi.registry.KernelRegistryEntry;
import org.jboss.kernel.spi.dependency.KernelControllerContext;
import org.jboss.beans.metadata.spi.BeanMetaData;
import org.apache.log4j.Logger;
import javax.servlet.ServletContext;
import javax.servlet.ServletContextListener;
import javax.servlet.ServletContextEvent;
import java.net.URL;
import java.net.MalformedURLException;
import java.util.List;
/**
* <p>A kernel bootstrap with a life cycle triggered by the <code>ServletContextListener</code> interface.
* All beans will be injected as servlet context attributes. The bean xml file must be available as
* a servlet context resource under the path <i>/WEB-INF/jboss-beans.xml</i>.</p>
*
* <p>A special bean with the name <code>ServletContext</code> is injected in the kernel before the deployment
* of the beans from the xml file are deployed. Thus it is possible to inject the servlet context as a bean
* into other beans.</p>
*
* @todo specify an alternative logger name
* @todo implement the specification of an alternative xml file path
* @todo implement kernel validate ?
*
* @author <a href="mailto:julien@jboss.org">Julien Viet</a>
* @author <a href="mailto:theute@jboss.org">Thomas Heute</a>
* @version $Revision: 1.1 $
*/
public class WebBootstrap implements ServletContextListener
{
/**
* The servlet context init parameter name for the bean resource location. For instance for a web application
* resource it could be <i>/WEB-INF/my-beans.xml</i>, for the web application classloader resource it could be
* <i>org/jboss/portal/my-beans.xml</i>. If no init parameter is declared then the litteral value
* <i>/WEB-INF/jboss-beans.xml</i> is used and the lookup is done in the servlet context resourcees.
*/
public static final String BEANS_RESOURCE_LOCATION_KEY = "jboss.portal.mc.beans_resource_location";
/**
* The servlet context init parameter name for the bean resource type which can be the servlet context
* or the web application classloader. If no value is specified the servlet context will be used for
* resource lookup. The legal values are <i>context</i> for the servlet context and <i>classloader</i>
* for the web application classloader.
*/
public static final String BEANS_RESOURCE_TYPE_KEY = "jboss.portal.mc.beans_resource_type";
/** Default value for the bean resource location. */
public static final String DEFAULT_JBOSS_BEANS_RESOURCE_LOCATION = "/WEB-INF/jboss-beans.xml";
/** Servlet context resource type. */
public static final String CONTEXT_RESOURCE_TYPE = "context";
/** Classloader resource type. */
public static final String CLASSLOADER_RESOURCE_TYPE = "classloader";
/** Prefix to bean service names in the servlet context */
public static final String BEAN_PREFIX = "jboss.portal:service=";
/** . */
private final static Logger log = Logger.getLogger(WebBootstrap.class);
/** . */
private ServletContext servletContext;
/** . */
private BeanXMLDeployer deployer;
/** . */
private KernelDeployment deployment;
/** . */
// private boolean registered;
/** . */
private ActualBootstrap bootstrap;
/** . */
private KernelControllerContext servletContextControllerContext;
public void contextInitialized(ServletContextEvent event)
{
servletContext = event.getServletContext();
//
try
{
bootstrap = new ActualBootstrap(this);
//
bootstrap.run();
//
log.info("Web kernel started");
}
catch (Exception e)
{
log.info("Web kernel boostrap failed", e);
}
}
public void contextDestroyed(ServletContextEvent event)
{
log.info("Web kernel shutdown");
//
if (deployment != null)
{
deployer.undeploy(deployment);
}
//
if (servletContextControllerContext != null)
{
bootstrap.getKernel().getController().uninstall("ServletContext");
}
//
servletContext = null;
//
log.info("Web kernel stopped");
}
/**
* Register a MC Bean in the servlet context prefixed with WebBoostrap.BEAN_PREFIX
*/
private void registerBean(BeanMetaData bean)
{
KernelRegistryEntry entry = bootstrap.getKernel().getRegistry().getEntry(bean.getName());
Object target = entry.getTarget();
servletContext.setAttribute(BEAN_PREFIX + bean.getName(), target);
}
void boostrap() throws Throwable
{
//
deployer = new BeanXMLDeployer(bootstrap.getKernel());
/*
//
AbstractBeanMetaData beanMD = new AbstractBeanMetaData("ServletContext", ServletContext.class.getName());
AbstractConstructorMetaData ctorMD = new AbstractConstructorMetaData();
ctorMD.setFactory(new AbstractValueMetaData(new ServletContextFactory(servletContext)));
ctorMD.setFactoryMethod("getInstance");
beanMD.setConstructor(ctorMD);
servletContextControllerContext = bootstrap.getKernel().getController().install(beanMD);
*/
//
URL url = getBeansURL();
//
if (url != null)
{
log.debug("About to deploy beans url=" + url);
deployment = deployer.deploy(url);
deployer.validate(deployment);
List<BeanMetaData> beans = deployment.getBeans();
for (BeanMetaData bean: beans)
{
registerBean(bean);
}
}
else
{
log.error("No valid beans URL was determined");
}
}
protected URL getBeansURL()
{
String location = servletContext.getInitParameter(BEANS_RESOURCE_LOCATION_KEY);
String type = servletContext.getInitParameter(BEANS_RESOURCE_TYPE_KEY);
//
if (location == null)
{
location = DEFAULT_JBOSS_BEANS_RESOURCE_LOCATION;
type = CONTEXT_RESOURCE_TYPE;
}
else if (type == null)
{
type = CONTEXT_RESOURCE_TYPE;
}
//
if (CONTEXT_RESOURCE_TYPE.equals(type))
{
try
{
return servletContext.getResource(location);
}
catch (MalformedURLException e)
{
log.error("Cannot obtain beans definition file from servlet context with location=" + location, e);
//
return null;
}
}
else if (CLASSLOADER_RESOURCE_TYPE.equals(type))
{
URL resource = Thread.currentThread().getContextClassLoader().getResource(location);
//
if (resource == null)
{
log.error("Cannot obtain bean definition file from thread context classloader with location=" + location);
}
//
return resource;
}
else
{
log.error("Cannot obtain bean definition file since the context type cannot be determined type=" + type);
//
return null;
}
}
}