/******************************************************************************
* JBoss, a division of Red Hat *
* Copyright 2008, Red Hat Middleware, LLC, 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.gatein.pc.portlet.impl.container;
import org.gatein.common.logging.LoggerFactory;
import org.gatein.pc.portlet.container.managed.ManagedObject;
import org.gatein.pc.portlet.container.managed.LifeCycleStatus;
import org.gatein.pc.portlet.container.managed.ManagedObjectFailedEvent;
import org.gatein.pc.portlet.container.managed.ManagedObjectRegistryEventListener;
import org.gatein.pc.portlet.container.managed.ManagedObjectLifeCycleEvent;
import org.gatein.common.logging.Logger;
import java.util.Set;
import java.util.HashSet;
/**
* @author <a href="mailto:julien@jboss.org">Julien Viet</a>
* @version $Revision: 630 $
*/
public abstract class LifeCycle implements ManagedObject
{
/** . */
private static final ThreadLocal<Set<Object>> faileds = new ThreadLocal<Set<Object>>();
/** . */
private Logger log = LoggerFactory.getLogger(LifeCycle.class);
/** . */
private LifeCycleStatus status = LifeCycleStatus.INITIALIZED;
/** Cheap reentrancy detection. */
private boolean active = false;
/** . */
private Throwable failure;
public final LifeCycleStatus getStatus()
{
return status;
}
@Override
public Throwable getFailure()
{
return failure;
}
@Override
public final void managedStart() throws IllegalStateException
{
promote(LifeCycleStatus.STARTED);
}
/**
* Attempt to promote the managed object.
*
* @throws IllegalStateException when reentrency is detected
*/
final synchronized void promote(LifeCycleStatus to) throws IllegalStateException
{
if (active)
{
throw new IllegalStateException("Reentrancy detected");
}
// Avoid attempt to re promote if failed previously
boolean clearFaileds = false;
if (faileds.get() == null)
{
clearFaileds = true;
faileds.set(new HashSet<Object>());
}
else if (faileds.get().contains(this))
{
return;
}
//
active = true;
failure = null;
try
{
while (to.getStage() > status.getStage())
{
LifeCycleStatus current = status;
promote();
if (current == status)
{
break;
}
}
//
promoteDependents(to);
}
finally
{
if (clearFaileds)
{
faileds.set(null);
}
active = false;
}
}
private void promote() throws IllegalStateException
{
LifeCycleStatus to = status.getPromotion();
//
if (to != null)
{
Throwable failure = null;
try
{
LifeCycleStatus next = status;
try
{
switch (to)
{
case CREATED:
invokeCreate();
break;
case STARTED:
invokeStart();
break;
}
next = to;
}
catch (DependencyNotResolvedException ignore)
{
// We stay in current status
}
catch (Exception e)
{
log.error("Cannot promote object to " + to, e);
failure = e;
}
catch (Error e)
{
log.error("Cannot promote object to " + to, e);
failure = e;
}
finally
{
this.status = next;
//
if (failure != null)
{
faileds.get().add(this);
}
}
//
if (failure == null)
{
if (next == to)
{
getListener().onEvent(new ManagedObjectLifeCycleEvent(this, next));
}
}
else
{
getListener().onEvent(new ManagedObjectFailedEvent(this, next));
}
}
finally
{
this.failure = failure;
}
}
}
public final void managedDestroy()
{
demote(LifeCycleStatus.INITIALIZED);
}
/**
* Attempt to demote the managed object.
*
* @throws IllegalStateException when reentrency is detected
*/
final synchronized void demote(LifeCycleStatus to) throws IllegalStateException
{
if (active)
{
throw new IllegalStateException("Reentrancy detected");
}
//
active = true;
failure = null;
try
{
demoteDependents(to);
//
while (to.getStage() < status.getStage())
{
LifeCycleStatus current = status;
demote();
if (current == status)
{
break;
}
}
}
finally
{
active = false;
}
}
private void demote() throws IllegalStateException
{
LifeCycleStatus to = status.getDemotion();
//
if (to != null)
{
try
{
switch (to)
{
case CREATED:
invokeStop();
break;
case INITIALIZED:
invokeDestroy();
break;
}
}
catch (Exception e)
{
log.error("Error during object demotion to " + to, e);
}
catch (Error e)
{
log.error("Error during object demotion to " + to, e);
}
finally
{
status = to;
}
//
getListener().onEvent(new ManagedObjectLifeCycleEvent(this, to));
}
}
protected void promoteDependents(LifeCycleStatus to)
{
}
protected void demoteDependents(LifeCycleStatus to)
{
}
protected abstract void invokeCreate() throws Exception;
protected abstract void invokeStart() throws Exception;
protected abstract void invokeStop();
protected abstract void invokeDestroy() throws Exception;
protected abstract ManagedObjectRegistryEventListener getListener();
}