/*
* JacORB - a free Java ORB
*
* Copyright (C) 1999-2004 Gerald Brose
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
package org.jacorb.notification.servant;
import java.io.PrintWriter;
import java.io.StringWriter;
import org.jacorb.config.*;
import org.jacorb.notification.OfferManager;
import org.jacorb.notification.SubscriptionManager;
import org.jacorb.notification.conf.Attributes;
import org.jacorb.notification.conf.Default;
import org.jacorb.notification.engine.AbstractRetryStrategy;
import org.jacorb.notification.engine.PushOperation;
import org.jacorb.notification.engine.PushTaskExecutor;
import org.jacorb.notification.engine.PushTaskExecutorFactory;
import org.jacorb.notification.engine.RetryException;
import org.jacorb.notification.engine.RetryStrategy;
import org.jacorb.notification.engine.RetryStrategyFactory;
import org.jacorb.notification.engine.TaskProcessor;
import org.jacorb.notification.interfaces.IProxyPushSupplier;
import org.jacorb.util.ObjectUtil;
import org.omg.CORBA.ORB;
import org.omg.CosNotifyChannelAdmin.ConsumerAdmin;
import org.omg.PortableServer.POA;
import org.picocontainer.MutablePicoContainer;
import org.picocontainer.defaults.DefaultPicoContainer;
import edu.emory.mathcs.backport.java.util.concurrent.Semaphore;
import edu.emory.mathcs.backport.java.util.concurrent.TimeUnit;
import edu.emory.mathcs.backport.java.util.concurrent.atomic.AtomicBoolean;
import edu.emory.mathcs.backport.java.util.concurrent.atomic.AtomicInteger;
import edu.emory.mathcs.backport.java.util.concurrent.atomic.AtomicReference;
/**
* @jmx.mbean extends = "AbstractProxySupplierMBean"
* @jboss.xmbean
*
* @--jmx.notification name = "notification.proxy.push_failed" description = "push to
* ProxyPushConsumer failed" notificationType = "java.lang.String"
*
* @author Alphonse Bendt
* @version $Id: AbstractProxyPushSupplier.java,v 1.10 2009-04-25 10:08:51 andre.spiegel Exp $
*/
public abstract class AbstractProxyPushSupplier extends AbstractProxySupplier implements
IProxyPushSupplier
{
private static final String NOTIFY_PUSH_FAILED = "notification.proxy.push_failed";
private final AtomicReference retryStrategyFactory_;
/**
* flag to indicate that this ProxySupplier should invoke remote calls (push) during
* deliverMessage.
*/
private final AtomicBoolean enabled_ = new AtomicBoolean(true);
private final PushTaskExecutor pushTaskExecutor_;
private final AtomicInteger pushCounter_ = new AtomicInteger(0);
private final AtomicInteger pushErrors_ = new AtomicInteger(0);
/**
* number of concurrent push operations allowed.
*/
protected final Semaphore pushSync_ = new Semaphore(1);
private final PushTaskExecutor.PushTask pushTask_ = new PushTaskExecutor.PushTask()
{
public void doPush()
{
if (isEnabled())
{
tryPushEvent();
}
}
public void cancel()
{
// ignore, only depends on settings of ProxyPushSupplier
}
};
private final PushTaskExecutor.PushTask flushTask_ = new PushTaskExecutor.PushTask()
{
public void doPush()
{
if (isEnabled())
{
flushPendingEvents();
}
}
public void cancel()
{
// ignore, only depends on settings of ProxyPushSupplier
}
};
public AbstractProxyPushSupplier(IAdmin admin, ORB orb, POA poa, Configuration conf,
TaskProcessor taskProcessor, PushTaskExecutorFactory pushTaskExecutorFactory,
OfferManager offerManager, SubscriptionManager subscriptionManager,
ConsumerAdmin consumerAdmin) throws ConfigurationException
{
super(admin, orb, poa, conf, taskProcessor, offerManager, subscriptionManager,
consumerAdmin);
pushTaskExecutor_ = pushTaskExecutorFactory.newExecutor(this);
retryStrategyFactory_ = new AtomicReference(newRetryStrategyFactory(conf, taskProcessor));
eventTypes_.add(NOTIFY_PUSH_FAILED);
}
private boolean tryPushEvent()
{
try
{
boolean _acquired = pushSync_.tryAcquire(1000, TimeUnit.MILLISECONDS);
if (_acquired)
{
try
{
return pushEvent();
}
finally
{
pushSync_.release();
}
}
// the scheduled push was not processed.
// therfor we need to schedule a push again.
schedulePush();
}
catch (InterruptedException e)
{
// ignored
}
return true;
}
protected abstract boolean pushEvent();
protected void handleFailedPushOperation(PushOperation operation, Exception error)
{
logger_.warn("handle failed pushoperation", error);
if (isDestroyed())
{
operation.dispose();
return;
}
StringWriter out = new StringWriter();
error.printStackTrace(new PrintWriter(out));
sendNotification(NOTIFY_PUSH_FAILED, "Push Operation failed", out.toString());
pushErrors_.getAndIncrement();
incErrorCounter();
if (AbstractRetryStrategy.isFatalException(error))
{
// push operation caused a fatal exception
// destroy the ProxySupplier
if (logger_.isWarnEnabled())
{
logger_.warn("push raised " + error + ": will destroy ProxySupplier, "
+ "disconnect Consumer", error);
}
operation.dispose();
destroy();
}
else if (!isRetryAllowed())
{
logger_.warn("no more retries allowed. disconnect consumer");
operation.dispose();
destroy();
}
else if (!isDestroyed())
{
final RetryStrategy _retry = newRetryStrategy(this, operation);
try
{
_retry.retry();
} catch (RetryException e)
{
logger_.error("retry failed", e);
_retry.dispose();
destroy();
}
}
else
{
// retry allowed && isDestroyed
throw new IllegalStateException("should not happen");
}
}
private RetryStrategy newRetryStrategy(IProxyPushSupplier pushSupplier,
PushOperation pushOperation)
{
return ((RetryStrategyFactory) retryStrategyFactory_.get()).newRetryStrategy(pushSupplier,
pushOperation);
}
private RetryStrategyFactory newRetryStrategyFactory(Configuration config,
TaskProcessor taskProcessor) throws ConfigurationException
{
final String factoryName = config.getAttribute(Attributes.RETRY_STRATEGY_FACTORY,
Default.DEFAULT_RETRY_STRATEGY_FACTORY);
try
{
return newRetryStrategyFactory(config, taskProcessor, factoryName);
} catch (ClassNotFoundException e)
{
throw new ConfigurationException(Attributes.RETRY_STRATEGY_FACTORY, e);
}
}
/**
* @jmx.managed-attribute description = "Factory used to control RetryPolicy" access =
* "read-write"
*/
public void setRetryStrategy(String factoryName) throws ClassNotFoundException
{
RetryStrategyFactory factory = newRetryStrategyFactory(config_, getTaskProcessor(),
factoryName);
retryStrategyFactory_.set(factory);
logger_.info("set RetryStrategyFactory: " + factoryName);
}
/**
* @jmx.managed-attribute description = "Factory used to control RetryPolicy" access =
* "read-write"
*/
public String getRetryStrategy()
{
return retryStrategyFactory_.get().getClass().getName();
}
private RetryStrategyFactory newRetryStrategyFactory(Configuration config,
TaskProcessor taskProcessor, String factoryName) throws ClassNotFoundException
{
final Class factoryClazz = ObjectUtil.classForName(factoryName);
final MutablePicoContainer pico = new DefaultPicoContainer();
pico.registerComponentInstance(TaskProcessor.class, taskProcessor);
pico.registerComponentImplementation(RetryStrategyFactory.class, factoryClazz);
pico.registerComponentInstance(config);
return (RetryStrategyFactory) pico.getComponentInstance(RetryStrategyFactory.class);
}
public final void schedulePush()
{
if (isEnabled())
{
scheduleTask(pushTask_);
}
}
public void scheduleFlush()
{
if (isEnabled())
{
scheduleTask(flushTask_);
}
}
public final void scheduleTask(PushTaskExecutor.PushTask pushTask)
{
if (!isDestroyed() && !isSuspended())
{
pushTaskExecutor_.executePush(pushTask);
}
}
public void flushPendingEvents()
{
while (tryPushEvent())
{
// nothing
}
}
public final void messageQueued()
{
if (isEnabled())
{
schedulePush();
}
}
public void resetErrorCounter()
{
super.resetErrorCounter();
pushCounter_.getAndIncrement();
enableDelivery();
}
public void disableDelivery()
{
boolean _wasEnabled = enabled_.getAndSet(false);
if (_wasEnabled)
{
logger_.warn("disabled delivery to ProxySupplier temporarily");
}
}
protected boolean isEnabled()
{
return enabled_.get();
}
private void enableDelivery()
{
boolean _wasEnabled = enabled_.getAndSet(true);
if (!_wasEnabled)
{
logger_.debug("enabled delivery to ProxySupplier");
}
}
/**
* @jmx.managed-attribute description = "Total Number of Push Operations" access = "read-only"
*/
public int getPushOperationCount()
{
return pushCounter_.get();
}
/**
* @jmx.managed-attribute description = "Number of failed Push-Operations" access = "read-only"
*/
public int getPushErrorCount()
{
return pushErrors_.get();
}
/**
* @jmx.managed-attribute description = "Average time (in ms) per Push-Operation" access =
* "read-only"
*/
public int getAveragePushDuration()
{
return (int) getCost() / getPushOperationCount();
}
}