/*
* JBoss, Home of Professional Open Source.
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file 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.aspects.versioned;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import java.util.concurrent.TimeUnit;
import org.jboss.aop.InstanceAdvised;
import org.jboss.aop.util.PayloadKey;
import org.jboss.logging.Logger;
import org.jboss.util.id.GUID;
/**
*
* @author <a href="mailto:bill@jboss.org">Bill Burke</a>
* @version $Revision: 89144 $
*/
public abstract class StateManager implements java.io.Externalizable
{
public static final String STATE_MANAGER = "STATE_MANAGER";
protected static Logger log = Logger.getLogger(StateManager.class);
public static StateManager getStateManager(InstanceAdvised obj)
{
return (StateManager)obj._getInstanceAdvisor().getMetaData().getMetaData(STATE_MANAGER, STATE_MANAGER);
}
public static void setStateManager(InstanceAdvised obj, StateManager manager)
{
obj._getInstanceAdvisor().getMetaData().addMetaData(STATE_MANAGER, STATE_MANAGER, manager, PayloadKey.TRANSIENT);
}
protected GUID guid;
protected long timeout;
transient protected ReadWriteLock lock = new ReentrantReadWriteLock();
public StateManager() {}
public StateManager(GUID guid, long timeout)
{
this.guid = guid;
this.timeout = timeout;
}
public ReadWriteLock getLock() { return lock; }
public GUID getGUID() { return guid; }
public void acquireWriteLock()
{
try
{
if (!lock.writeLock().tryLock(timeout, TimeUnit.MILLISECONDS))
{
throw new LockAttemptFailure("failed to acquire write lock: " + guid);
}
log.trace("writelock acquired for: " + guid);
}
catch (InterruptedException ignored)
{
Thread.currentThread().interrupt();
throw new LockAttemptFailure("failed to acquire write lock: " + guid);
}
}
public void acquireReadLock()
{
try
{
if (!lock.readLock().tryLock(timeout, TimeUnit.MILLISECONDS))
{
throw new LockAttemptFailure("failed to acquire read lock: " + guid);
}
log.trace("readlock acquired for: " + guid);
}
catch (InterruptedException ignored)
{
Thread.currentThread().interrupt();
throw new LockAttemptFailure("failed to acquire read lock: " + guid);
}
}
public void releaseReadLock()
{
lock.readLock().unlock();
log.trace("readlock released for: " + guid);
}
public void releaseWriteLock()
{
lock.writeLock().unlock();
log.trace("writelock released for: " + guid);
}
public void writeExternal(java.io.ObjectOutput out)
throws java.io.IOException
{
out.writeObject(guid);
out.writeLong(timeout);
}
public void readExternal(java.io.ObjectInput in)
throws java.io.IOException, ClassNotFoundException
{
this.guid = (GUID)in.readObject();
this.timeout = in.readLong();
this.lock = new ReentrantReadWriteLock();
}
}