org.glassfish.osgijavaeebase.ExtenderManager Maven / Gradle / Ivy
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 2009-2012 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package org.glassfish.osgijavaeebase;
import org.glassfish.api.event.EventListener;
import org.glassfish.api.event.EventTypes;
import org.glassfish.api.event.Events;
import org.glassfish.embeddable.GlassFish;
import org.glassfish.embeddable.GlassFishException;
import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceReference;
import org.osgi.util.tracker.ServiceTracker;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* It is responsible for starting any registered {@link Extender} service
* after GlassFish server is started and stopping them when server is shutdown.
* We use GlassFish STARTED event to be notified of server startup and shutdown.
* We don't depend on HK2 service registry because of compatibility with GlassFish 3.1.x.
* We use embeddable GlassFish instead to locate services.
*
* @author [email protected]
*/
class ExtenderManager
{
private static final Logger logger =
Logger.getLogger(ExtenderManager.class.getPackage().getName());
private BundleContext context;
private Events events;
private EventListener listener;
private ServiceTracker extenderTracker;
private GlassFishServerTracker glassFishServerTracker; // used to track starting of GlassFish
public ExtenderManager(BundleContext context)
{
this.context = context;
}
public synchronized void start() throws Exception
{
logger.logp(Level.FINE, "ExtenderManager", "start", "ExtenderManager starting");
glassFishServerTracker = new GlassFishServerTracker(context);
glassFishServerTracker.open();
}
public synchronized void stop() throws Exception
{
logger.logp(Level.FINE, "ExtenderManager", "start", "ExtenderManager stopping");
unregisterGlassFishShutdownHook();
if (glassFishServerTracker != null) {
glassFishServerTracker.close();
glassFishServerTracker = null;
}
stopExtenders();
}
private synchronized void startExtenders() {
logger.entering("ExtenderManager", "startExtenders");
// Because of a race condition, we can be started multiple times, so check if already started
if (extenderTracker != null) return;
// open will call addingService for each existing extender
// and there by we will start each extender.
extenderTracker = new ExtenderTracker(context);
extenderTracker.open();
}
private synchronized void stopExtenders()
{
logger.entering("ExtenderManager", "stopExtenders");
// Because of a race condition, we can be stopped multiple times, so check if already started
// more over, extenderTracker will be null until server is started, so to avoid NPE, null check is needed.
if (extenderTracker == null) return;
// close will call removedService for each tracked extender
// and there by we will stop each extender.
extenderTracker.close();
extenderTracker = null;
}
private void unregisterGlassFishShutdownHook() {
if (listener != null) {
events.unregister(listener);
}
}
private class ExtenderTracker extends ServiceTracker {
ExtenderTracker(BundleContext context)
{
super(context, Extender.class.getName(), null);
}
@Override
public Object addingService(ServiceReference reference)
{
Extender e = Extender.class.cast(context.getService(reference));
logger.logp(Level.FINE, "ExtenderManager$ExtenderTracker", "addingService",
"Starting extender called {0}", new Object[]{e});
e.start();
return e;
}
@Override
public void removedService(ServiceReference reference, Object service) {
Extender e = Extender.class.cast(context.getService(reference));
logger.logp(Level.FINE, "ExtenderManager$ExtenderTracker", "removedService",
"Stopping extender called {0}", new Object[]{e});
e.stop();
}
}
/**
* Tracks GlassFish and obtains EVents service from it and registers a listener
* that takes care of actually starting and stopping other extenders.
*/
private class GlassFishServerTracker extends ServiceTracker {
public GlassFishServerTracker(BundleContext context)
{
super(context, GlassFish.class.getName(), null);
}
@Override
public Object addingService(ServiceReference reference)
{
logger.logp(Level.FINE, "ExtenderManager$GlassFishServerTracker",
"addingService", "GlassFish has been created");
final GlassFish gf = GlassFish.class.cast(context.getService(reference));
ExecutorService executorService = Executors.newSingleThreadExecutor();
return executorService.submit(new Runnable() {
@Override
public void run() {
try {
// Poll for GlassFish to start. GlassFish service might have been registered by
// GlassFishRuntime.newGlassFish() and hence might not be ready to use.
// This is the case for GlassFish < 4.0
GlassFish.Status status;
while ((status = gf.getStatus()) != GlassFish.Status.STARTED) {
if (status == GlassFish.Status.DISPOSED) return;
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
return;
}
}
// start extenders first before registering for events, otherwise we can deadlock
// if startExtender() is in progress and glassfish sends PREPARE_SHUTDOWN event.
startExtenders();
events = gf.getService(Events.class);
listener = new EventListener() {
public void event(Event event) {
if (EventTypes.PREPARE_SHUTDOWN.equals(event.type())) {
stopExtenders();
}
}
};
events.register(listener);
} catch (GlassFishException e) {
throw new RuntimeException(e); // TODO(Sahoo): Proper Exception Handling
}
}
});
}
@Override
public void removedService(ServiceReference reference, Object service) {
Future future = (Future) service;
future.cancel(true); // interrupt if it is still waiting for gf to start or stop
super.removedService(reference, service);
}
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy