/*
* JBoss, Home of Professional Open Source
* Copyright 2005, JBoss Inc., 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.jboss.messaging.core.impl.clusterconnection;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageListener;
import javax.jms.Session;
import javax.transaction.Transaction;
import javax.transaction.TransactionManager;
import org.jboss.jms.client.JBossSession;
import org.jboss.jms.client.container.ClientConsumer;
import org.jboss.jms.client.delegate.ClientConsumerDelegate;
import org.jboss.jms.client.state.ConsumerState;
import org.jboss.jms.delegate.ProducerDelegate;
import org.jboss.jms.delegate.SessionDelegate;
import org.jboss.jms.destination.JBossQueue;
import org.jboss.jms.message.JBossMessage;
import org.jboss.jms.message.MessageProxy;
import org.jboss.logging.Logger;
import org.jboss.messaging.core.contract.Queue;
/**
*
* @author <a href="mailto:tim.fox@jboss.com">Tim Fox</a>
* @version <tt>$Revision: $</tt>20 Jun 2007
*
* $Id: $
*
*/
public class MessageSucker implements MessageListener
{
private static final Logger log = Logger.getLogger(MessageSucker.class);
private boolean trace = log.isTraceEnabled();
private Queue localQueue;
private Session sourceSession;
private Session localSession;
private ProducerDelegate producer;
private volatile boolean started;
private TransactionManager tm;
private boolean consuming;
private ClientConsumerDelegate consumer;
private ClientConsumer clientConsumer;
private boolean preserveOrdering;
private long sourceChannelID;
protected JBossQueue jbq;
private boolean suspended = false;
public String toString()
{
return "MessageSucker:" + System.identityHashCode(this) + " queue:" + localQueue.getName();
}
protected MessageSucker(Queue localQueue, Session sourceSession, Session localSession,
boolean preserveOrdering, long sourceChannelID)
{
if (trace) { log.trace("Creating message sucker, localQueue:" + localQueue + " preserveOrdering:" + preserveOrdering); }
this.jbq = new JBossQueue(localQueue.getName(), true);
this.localQueue = localQueue;
this.sourceSession = sourceSession;
this.localSession = localSession;
this.preserveOrdering = preserveOrdering;
this.sourceChannelID = sourceChannelID;
}
protected synchronized void start() throws Exception
{
if (started)
{
return;
}
if (trace) { log.trace(this + " starting"); }
SessionDelegate localdel = ((JBossSession)localSession).getDelegate();
producer = localdel.createProducerDelegate(jbq);
//We create the consumer with autoFlowControl = false
//In this mode, the consumer does not handle it's own flow control, but it must be handled
//manually using changeRate() methods
//The local queue itself will manually send these messages depending on its state -
//So effectively the message buffering is handled by the local queue, not the ClientConsumer
SessionDelegate sourcedel = ((JBossSession)sourceSession).getDelegate();
consumer = (ClientConsumerDelegate)sourcedel.createConsumerDelegate(jbq, null, false, null, false, false);
clientConsumer = ((ConsumerState)consumer.getState()).getClientConsumer();
consumer.setMessageListener(this);
started = true;
//Register ourselves with the local queue - this queue will handle flow control for us
if (trace) { log.trace(this + " Registering sucker"); }
localQueue.registerSucker(this);
if (trace) { log.trace(this + " Registered sucker"); }
}
protected void stop()
{
localQueue.unregisterSucker(this);
synchronized (this)
{
if (!started)
{
return;
}
setConsuming(false);
try
{
consumer.closing(-1);
}
catch (Throwable t)
{
// Ignore
}
try
{
consumer.close();
}
catch (Throwable t)
{
// Ignore
}
try
{
producer.close();
}
catch (Throwable t)
{
// Ignore
}
sourceSession = null;
localSession = null;
consumer = null;
clientConsumer = null;
producer = null;
started = false;
}
}
//the suspend stops the sucker's receiving end but doesn't unregister the sucker.
//we only suspend the consumer side.
public synchronized void suspend()
{
if (!started || suspended)
{
return;
}
boolean oldConsuming = consuming;
setConsuming(false);
consuming = oldConsuming;
suspended = true;
sourceSession = null;
consumer = null;
clientConsumer = null;
}
public synchronized void resume(Session srcSession) throws JMSException
{
if (!suspended)
{
return;
}
sourceSession = srcSession;
SessionDelegate sourcedel = ((JBossSession)sourceSession).getDelegate();
consumer = (ClientConsumerDelegate)sourcedel.createConsumerDelegate(jbq, null, false, null, false, false);
clientConsumer = ((ConsumerState)consumer.getState()).getClientConsumer();
try
{
if (consuming)
{
if (trace) { log.trace(this + " resuming client consumer"); }
clientConsumer.resume();
}
else
{
if (trace) { log.trace(this + " pausing client consumer"); }
clientConsumer.pause();
}
}
catch (Exception e)
{
e.printStackTrace();
//We ignore the exception - we might fail to change rate when stoping a sucker for a dead server
}
consumer.setMessageListener(this);
suspended = false;
}
public String getQueueName()
{
return this.localQueue.getName();
}
public synchronized void setConsuming(boolean consume)
{
if (trace) { log.trace(this + " setConsuming " + consume); }
if (!started)
{
return;
}
//for supended, we set the consuming flag and do nothing.
//later on resume, we force the sucker to be the last set consuming state.
if (suspended)
{
consuming = consume;
return;
}
try
{
if (consume && !consuming)
{
if (trace) { log.trace(this + " resuming client consumer"); }
clientConsumer.resume();
consuming = true;
}
else if (!consume && consuming)
{
if (trace) { log.trace(this + " pausing client consumer"); }
clientConsumer.pause();
consuming = false;
}
}
catch (Exception e)
{
//We ignore the exception - we might fail to change rate when stoping a sucker for a dead server
}
}
public void onMessage(Message msg)
{
Transaction tx = null;
try
{
if (trace) { log.trace(this + " sucked message " + msg + " JMSDestination - " + msg.getJMSDestination()); }
Destination originalDestination = msg.getJMSDestination();
org.jboss.messaging.core.contract.Message coreMessage = ((MessageProxy)msg).getMessage();
if (preserveOrdering)
{
//Add a header saying we have sucked the message
coreMessage.putHeader(org.jboss.messaging.core.contract.Message.CLUSTER_SUCKED, "x");
}
//Add a header with the node id of the node we sucked from - this is used on the sending end to do
//the move optimisation
coreMessage.putHeader(org.jboss.messaging.core.contract.Message.SOURCE_CHANNEL_ID, sourceChannelID);
long timeToLive = msg.getJMSExpiration();
if (timeToLive != 0)
{
timeToLive -= System.currentTimeMillis();
if (timeToLive <= 0)
{
timeToLive = 1; //Should have already expired - set to 1 so it expires when it is consumed or delivered
}
}
//First we ack it - this ack only occurs in memory even if it is a persistent message
msg.acknowledge();
if (trace) { log.trace("Acknowledged message"); }
coreMessage.getHeaders().put(JBossMessage.JBOSS_MESSAGING_ORIG_DESTINATION_SUCKER, originalDestination);
synchronized (localSession)
{
//Then we send - this causes the ref to be moved (SQL UPDATE) in the database
producer.send(null, msg, msg.getJMSDeliveryMode(), msg.getJMSPriority(), timeToLive, true);
if (trace) { log.trace(this + " forwarded message to queue"); }
}
}
catch (Exception e)
{
log.error("Failed to forward message", e);
try
{
if (tx != null) tm.rollback();
}
catch (Throwable t)
{
if (trace) { log.trace("Failed to rollback tx", t); }
}
}
}
}