/*
* JBoss, Home of Professional Open Source.
* Copyright 2010, Red Hat, Inc., and individual contributors
* as indicated by the @author tags. See the copyright.txt file 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.jboss.as.naming;
import java.util.Hashtable;
import javax.naming.Context;
import javax.naming.Name;
import javax.naming.RefAddr;
import javax.naming.Reference;
import org.jboss.as.naming.context.ModularReference;
import org.jboss.as.naming.logging.NamingLogger;
import org.jboss.msc.service.ServiceController;
import org.jboss.msc.service.ServiceName;
import org.jboss.msc.service.ServiceNotFoundException;
import org.jboss.msc.service.ServiceRegistry;
import org.jboss.msc.service.StabilityMonitor;
/**
* Abstract object factory that allows for the creation of service references. Object factories that subclass
* {@link ServiceReferenceObjectFactory} can get access to the value of the service described by the reference.
* <p/>
* If the factory state is no {@link State#UP} then the factory will block. If the state is {@link State#START_FAILED} or
* {@link State#REMOVED} (or the state transactions to one of these states while blocking) an exception is thrown.
*
* @author Stuart Douglas
* @author <a href="mailto:ropalka@redhat.com">Richard Opalka</a>
*/
public class ServiceReferenceObjectFactory implements ServiceAwareObjectFactory {
private volatile ServiceRegistry serviceRegistry;
/**
* Create a reference to a sub class of {@link ServiceReferenceObjectFactory} that injects the value of the given service.
*/
public static Reference createReference(final ServiceName service, Class<? extends ServiceReferenceObjectFactory> factory) {
return ModularReference.create(Context.class, new ServiceNameRefAdr("srof", service), factory);
}
@Override
public void injectServiceRegistry(ServiceRegistry registry) {
this.serviceRegistry = registry;
}
@SuppressWarnings("unchecked")
@Override
public final Object getObjectInstance(Object obj, Name name, Context nameCtx, Hashtable<?, ?> environment) throws Exception {
final Reference reference = (Reference) obj;
final ServiceNameRefAdr nameAdr = (ServiceNameRefAdr) reference.get("srof");
if (nameAdr == null) {
throw NamingLogger.ROOT_LOGGER.invalidContextReference("srof");
}
final ServiceName serviceName = (ServiceName)nameAdr.getContent();
final ServiceController<?> controller;
try {
controller = serviceRegistry.getRequiredService(serviceName);
} catch (ServiceNotFoundException e) {
throw NamingLogger.ROOT_LOGGER.cannotResolveService(serviceName);
}
final StabilityMonitor monitor = new StabilityMonitor();
monitor.addController(controller);
try {
monitor.awaitStability();
} catch (InterruptedException e) {
throw NamingLogger.ROOT_LOGGER.threadInterrupt(serviceName);
} finally {
monitor.removeController(controller);
}
switch (controller.getState()) {
case UP:
return getObjectInstance(controller.getValue(), obj, name, nameCtx, environment);
case START_FAILED:
throw NamingLogger.ROOT_LOGGER.cannotResolveService(serviceName, getClass().getName(), "START_FAILED");
case REMOVED:
throw NamingLogger.ROOT_LOGGER.cannotResolveService(serviceName, getClass().getName(), "START_FAILED");
}
// we should never get here, as the listener should not notify unless the state was one of the above
throw NamingLogger.ROOT_LOGGER.cannotResolveServiceBug(serviceName, getClass().getName(), controller.getState().toString());
}
/**
* Handles the service reference. The parameters are the same as
* {@link javax.naming.spi.ObjectFactory#getObjectInstance(Object, Name, Context, Hashtable)}, but with the addition of the service value as
* the first parameter.
*/
public Object getObjectInstance(Object serviceValue, Object obj, Name name, Context nameCtx,
Hashtable<?, ?> environment) throws Exception {
return serviceValue;
}
private static final class ServiceNameRefAdr extends RefAddr {
private static final long serialVersionUID = 3677121114687908679L;
private final ServiceName serviceName;
private ServiceNameRefAdr(String s, ServiceName serviceName) {
super(s);
this.serviceName = serviceName;
}
public Object getContent() {
return serviceName;
}
}
}