/*
* Copyright (C) 2011 eXo Platform SAS.
*
* 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.exoplatform.services.transaction;
import org.exoplatform.services.log.ExoLogger;
import org.exoplatform.services.log.Log;
import javax.transaction.SystemException;
import javax.transaction.Transaction;
import javax.transaction.TransactionManager;
/**
* This class describes all the actions that are not supposed to be called
* within a transaction
*
* @author <a href="mailto:nfilotto@exoplatform.com">Nicolas Filotto</a>
* @version $Id$
*
*/
public abstract class ActionNonTxAware<R, A, E extends Exception>
{
/**
* The logger
*/
protected static final Log LOG = ExoLogger.getLogger("exo.jcr.component.core.ActionNonTxAware");
/**
* Executes the action outside the context of the current tx
* @param arg the argument to use to execute the action
* @return the result of the action
* @throws E if an error occurs while executing the action
*/
public R run(A... arg) throws E
{
final TransactionManager tm = getTransactionManager();
Transaction tx = null;
try
{
if (tm != null)
{
try
{
tx = tm.suspend();
}
catch (SystemException e)
{
LOG.warn("Cannot suspend the current transaction", e);
}
}
return execute(arg);
}
finally
{
if (tx != null)
{
try
{
tm.resume(tx);
}
catch (Exception e)
{
LOG.warn("Cannot resume the current transaction", e);
}
}
}
}
/**
* Executes the action outside the context of the current tx. This
* method is equivalent to {@link ActionNonTxAware#run(Object[])}} but
* with <tt>null</tt> as parameter.
* @return the result of the action
* @throws E if an error occurs while executing the action
*/
public R run() throws E
{
return run((A[])null);
}
/**
* Executes the action
* @param arg the argument to use to execute the action
* @return the result of the action
* @throws E if an error occurs while executing the action
*/
protected R execute(A... arg) throws E
{
if (arg == null || arg.length == 0)
{
return execute((A)null);
}
return execute(arg[0]);
}
/**
* Executes the action
* @param arg the argument to use to execute the action
* @return the result of the action
* @throws E if an error occurs while executing the action
*/
protected R execute(A arg) throws E
{
return null;
}
/**
* Gives the Transaction Manager that will be used while executing the action
* @return the {@link TransactionManager} to use
*/
protected abstract TransactionManager getTransactionManager();
}