/*
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Created on Apr 23, 2009
*/
package com.bigdata.service;
import java.util.Properties;
import java.util.concurrent.Callable;
import java.util.concurrent.Future;
import org.apache.log4j.Logger;
import com.bigdata.Banner;
/**
* A service for distributing application {@link Callable}s across an
* {@link IBigdataFederation}.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
abstract public class ClientService extends AbstractService implements
IClientService, ISession {
protected static final Logger log = Logger.getLogger(DataService.class);
/**
* Configuration options.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
public interface Options extends IBigdataClient.Options {
}
/**
* Properties from the ctor.
*/
private final Properties properties;
/**
* The dynamic property set associated with the service instance.
*/
private final Session session = new Session();
public Session getSession() {
return session;
}
public synchronized void shutdown() {
if (!isOpen())
return;
open = false;
}
public synchronized void shutdownNow() {
if (!isOpen())
return;
open = false;
}
final public boolean isOpen() {
return open;
}
private boolean open = true;
/**
*
*/
public ClientService(final Properties properties) {
// show the copyright banner during statup.
Banner.banner();
this.properties = (Properties) properties.clone();
}
@Override
public AbstractService start() {
/*
* Note: There is nothing to do here - the main "service" is the
* federation's executor service.
*/
return this;
}
/**
* Returns either {@link IClientService}.
*/
public Class<? extends IClientService> getServiceIface() {
return IClientService.class;
}
/**
* Note: When the {@link ClientService} is accessed via RMI the
* {@link Future} MUST be a proxy. This gets handled by the concrete server
* implementation.
*
* @see AbstractDistributedFederation#getProxy(Future)
*
* @todo Map/reduce can be handled in the this manner.
* <p>
* Note that we have excellent locators for the best data service when
* the map/reduce input is the scale-out repository since the task
* should run on the data service that hosts the file block(s). When
* failover is supported, the task can run on the service instance
* with the least load. When the input is a networked file system,
* then additional network topology smarts would be required to make
* good choices.
*
* @todo we should probably put the federation object in a sandbox in order
* to prevent various operations by tasks running in the
* {@link DataService} using the {@link IDataServiceCallable}
* interface to gain access to the {@link DataService}'s federation.
* for example, if they use {@link AbstractFederation#shutdownNow()}
* then the {@link DataService} itself would be shutdown.
*/
public Future<? extends Object> submit(final Callable<? extends Object> task) {
setupLoggingContext();
try {
if (task == null)
throw new IllegalArgumentException();
if (task instanceof IFederationCallable) {
((IFederationCallable) task).setFederation(getFederation());
}
// submit the task and return its Future.
return getFederation().getExecutorService().submit(task);
} finally {
clearLoggingContext();
}
}
/**
* Extended to attach the various performance counters reported by the
* {@link DistributedTransactionService}.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
static public class ClientServiceFederationDelegate extends
DefaultServiceFederationDelegate<ClientService> {
public ClientServiceFederationDelegate(final ClientService service) {
super(service);
}
// /**
// * Note: May be extended to setup service specific counters.
// *
// * @todo write the client URL onto a file in the service's data
// * directory.
// */
// public void didStart() {
//
// super.didStart();
//
// setupCounters();
//
// // logHttpdURL(dir);
//
// }
//
// /**
// * Sets up {@link AbstractTransactionService} specific counters.
// */
// protected void setupCounters() {
//
// if (getServiceUUID() == null) {
//
// throw new IllegalStateException(
// "The ServiceUUID is not available yet");
//
// }
//
// if (!service.isOpen()) {
//
// /*
// * The service has already been closed.
// */
//
// log.warn("Service is not open.");
//
// return;
//
// }
//
// /*
// * Service specific counters.
// */
//
// final CounterSet serviceRoot = service.getFederation()
// .getServiceCounterSet();
//
// serviceRoot.attach(service.getCounters());
//
// }
}
}