ServerResource.java

/*
 * JBoss, Home of Professional Open Source
 * Copyright 2006, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags.
 * See the copyright.txt in the distribution for a full listing
 * of individual contributors.
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU Lesser General Public License, v. 2.1.
 * This program is distributed in the hope that it will be useful, but WITHOUT A
 * 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,
 * v.2.1 along with this distribution; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA  02110-1301, USA.
 *
 * (C) 2005-2006,
 * @author JBoss Inc.
 */
/*
 * Copyright (C) 1998, 1999, 2000,
 *
 * Arjuna Solutions Limited,
 * Newcastle upon Tyne,
 * Tyne and Wear,
 * UK.
 *
 * $Id: ServerResource.java 2342 2006-03-30 13:06:17Z  $
 */

package com.arjuna.ats.internal.jts.interposition.resources.arjuna;

import java.util.Collections;
import java.util.LinkedList;
import java.util.List;

import com.arjuna.ats.arjuna.common.Uid;
import com.arjuna.ats.internal.jts.ORBManager;
import com.arjuna.ats.internal.jts.orbspecific.interposition.ServerControl;
import com.arjuna.ats.internal.jts.orbspecific.interposition.resources.arjuna.ServerNestedAction;
import com.arjuna.ats.jts.logging.jtsLogger;

/**
 * The base class from which interposed resources derive.
 * 
 * @author Mark Little (mark@arjuna.com)
 * @version $Id: ServerResource.java 2342 2006-03-30 13:06:17Z $
 * @since JTS 1.0.
 */

public class ServerResource
{

    /*
     * Assume only one thread can delete an object!
     */

    public void finalize () throws Throwable
    {
        if (jtsLogger.logger.isTraceEnabled())
        {
            jtsLogger.logger.trace("ServerResource.finalize ( " + _theUid
                    + " )");
        }

        tidyup();
    }

    /*
     * This is called to allow lazy interposition of resources. Since some
     * implementations of interposition may not need this, its default is to do
     * nothing.
     */

    public boolean interposeResource ()
    {
        return true;
    }

    public final boolean valid ()
    {
        return _valid;
    }

    public final synchronized boolean destroyed ()
    {
        return _destroyed;
    }

    public final ServerControl control ()
    {
        return _theControl;
    }

    /*
     * Add transaction to this transaction's children, and set the new
     * transaction's notion of its parent to us.
     */

    public final boolean addChild (ServerNestedAction c)
    {
        if (_children.add(c))
        {
            c.setParentHandle(this);
            return true;
        }

        return false;
    }

    public final boolean removeChild (ServerNestedAction c)
    {
        c.setParentHandle(null);
        return _children.remove(c);
    }

    public final ServerNestedAction getChild (Uid actUid)
    {
        synchronized (_children)
        {
            for (ServerNestedAction action : _children)
            {
                if (actUid.equals(action.get_uid()))
                {
                    return action;
                }
            }
        }

        return null;
    }

    public final List<ServerNestedAction> getChildren ()
    {
        return _children;
    }

    public final boolean abortChild (ServerNestedAction toAbort)
    {
        if (toAbort != null)
        {
            ServerNestedAction child;
            synchronized (_children)
            {
                child = getChild(toAbort.get_uid());
                if (child != null)
                {
                    _children.remove(child);
                }
            }

            if (child != null)
            {
                org.omg.CosTransactions.Status nestedStatus = child.otsStatus();

                if ((nestedStatus != org.omg.CosTransactions.Status.StatusRolledBack)
                        && (nestedStatus != org.omg.CosTransactions.Status.StatusCommitted)
                        && (nestedStatus != org.omg.CosTransactions.Status.StatusNoTransaction))
                {
                    child.rollback_subtransaction();
                }

                try
                {
                    ORBManager.getPOA().shutdownObject(child.theResource());
                }
                catch (Exception e)
                {
                }

                return true;
            }
            else
            {
                jtsLogger.i18NLogger
                        .warn_interposition_resources_arjuna_notchild("ServerResource.abortChild");
            }
        }
        else
        {
            jtsLogger.i18NLogger
                    .warn_interposition_resources_arjuna_nochild("ServerResource.abortChild");
        }

        return false;
    }

    public synchronized final void setParentHandle (ServerResource p)
    {
        _parent = p;
    }

    public synchronized final ServerResource getParentHandle ()
    {
        return _parent;
    }

    public Uid get_uid ()
    {
        return _theUid;
    }

    public final org.omg.CosTransactions.Status otsStatus ()
    {
        try
        {
            if (_theControl != null)
                return _theControl.getImplHandle().get_status();
            else
                return org.omg.CosTransactions.Status.StatusNoTransaction;
        }
        catch (Exception e)
        {
            return org.omg.CosTransactions.Status.StatusUnknown;
        }
    }

    public final String getChildren (int depth)
    {
        String children = "";

        synchronized (_children)
        {
            for (ServerNestedAction child : _children)
            {

                children += "\n";

                for (int i = 0; i < depth; i++)
                    children += " ";

                children += child.get_uid();
                children += child.getChildren(depth + 1);
            }
        }

        return children;
    }

    protected ServerResource()
    {
        if (jtsLogger.logger.isTraceEnabled())
        {
            jtsLogger.logger.trace("ServerResource::ServerResource ()");
        }

        _theControl = null;
        _parent = null;
        _valid = true;
        _destroyed = false;
    }

    protected ServerResource(ServerControl control)
    {
        _theControl = control;
        _theUid = control.get_uid();
        _parent = null;
        _valid = true;
        _destroyed = false;

        if (jtsLogger.logger.isTraceEnabled())
        {
            jtsLogger.logger.trace("ServerResource::ServerResource ( "
                    + _theUid + " )");
        }
    }

    protected void tidyup ()
    {
        synchronized (_children)
        {
            while (_children.size() > 0)
            {
                ServerNestedAction child = _children.remove(0);
                child.setParentHandle(null);
                try
                {
                    ORBManager.getPOA().shutdownObject(child.theResource());
                }
                catch (Exception e)
                {
                }
            }
        }

        if (_theControl != null)
        {
            /*
             * If it's a wrapper, then the control will not have been driven to
             * commit or rollback or forget, and hence will not have destroyed
             * itself. So, do so now.
             */

            if (_theControl.isWrapper())
            {
                try
                {
                    _theControl.destroy(); // will delete itself
                }
                catch (Exception e)
                {
                }
            }

            _theControl = null;
        }
    }

    protected ServerControl _theControl;

    protected final List<ServerNestedAction> _children = Collections
            .synchronizedList(new LinkedList<ServerNestedAction>());

    protected Uid _theUid;

    protected ServerResource _parent;

    protected boolean _valid;

    protected boolean _destroyed;

}