head	1.3;
access;
symbols;
locks; strict;
comment	@# @;


1.3
date	2001.05.21.21.06.01;	author leonardr;	state dead;
branches;
next	1.2;

1.2
date	2001.05.17.14.51.17;	author leonardr;	state Exp;
branches;
next	1.1;

1.1
date	2001.05.09.21.07.55;	author dlr;	state Exp;
branches;
next	;


desc
@@


1.3
log
@Moved clustering features out of RMI and into the database.
@
text
@/* ================================================================
 * Copyright (c) 2001 CollabNet.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * 1. Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 * any, must include the following acknowlegement: "This product includes
 * software developed by CollabNet <http://www.collab.net/>."
 * Alternately, this acknowlegement may appear in the software itself, if
 * and wherever such third-party acknowlegements normally appear.
 *
 * 4. The hosted project names must not be used to endorse or promote
 * products derived from this software without prior written
 * permission. For written permission, please contact info@@collab.net.
 *
 * 5. Products derived from this software may not use the "Tigris" or
 * "Helm" names nor may "Tigris" or "Helm" appear in their names without
 * prior written permission of CollabNet.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL COLLABNET OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of CollabNet.
 */

package org.tigris.helm.tool.cluster;

import java.util.Map;
import java.util.Hashtable;
import java.rmi.Remote;
import java.rmi.RemoteException;
import java.rmi.server.UnicastRemoteObject;

import org.apache.turbine.util.Log;

import org.tigris.helm.tool.cluster.ClusterSingletonMediator;
import org.tigris.helm.tool.cluster.ClusteredColleague;
import org.tigris.helm.tool.cluster.ClusteredSingletonColleague;
import org.tigris.helm.tool.cluster.MediatedEvent;
import org.tigris.helm.tool.cluster.PollEvent;
import org.tigris.helm.tool.cluster.PollTarget;

/**
 * Enforces the existance of one and only one operational thread across JVMs.
 *
 * @@author <a href="mailto:dlr@@collab.net">Daniel Rall</a>
 * @@author <a href="mailto:leonardr@@collab.net">Leonard Richardson</a>
 */
public abstract class BaseClusterSingletonMediator extends UnicastRemoteObject
    implements ClusterSingletonMediator
{
    private PollTarget singletonPoll;

    public BaseClusterSingletonMediator()
        throws RemoteException
    {
        singletonPoll = null;
    }

    public synchronized void register(ClusteredColleague colleague)
        throws RemoteException
    {
        try
        {
            if (getSingleton() == null)
            {
                // singletonPoll must be set before setAsSingleton() will work
                singletonPoll = new PollTarget(colleague);
                ((ClusteredSingletonColleague) colleague).setAsSingleton();
                Log.debug("BaseClusterSingletonMediator registered collague " +
                          "as singleton");
            }
            else
            {
                Log.debug("BaseClusterSingletonMediator already registered " +
                          "a singleton");
            }
        }
        catch (Exception e)
        {            
            Log.error(e);
            throw new RemoteException("Error registering colleague with " +
                                      "BaseClusterSingletonMediator: " +
                                      e.getMessage());
        }
    }

    public final void unregister(ClusteredColleague colleague)
        throws RemoteException
    {
        if (colleague == getSingleton())
        {
            singletonPoll = null;
        }        
    }

    public void handleEvent(MediatedEvent event)
        throws RemoteException
    {
        if (event instanceof PollEvent)
        {
            // Extract the answering colleague and handle its poll response.
            ClusteredSingletonColleague singleton = getSingleton();
            synchronized (singleton)
            {
                if (((PollEvent) event).getSource() == singleton)
                {
                    singletonPoll.setTimePolledAt(PollTarget.NOT_WAITING);
                }
            }
        }
        else
        {
            Log.warn("Unhandled cluster event sent to " +
                     "BaseClusterSingletonMediator: " + event.toString());
        }
    }

    public void sendEvent(MediatedEvent event)
        throws RemoteException
    {
        getSingleton().handleEvent(event);
    }

    public final ClusteredSingletonColleague getSingleton()
        throws RemoteException
    {
        return (singletonPoll == null ? null :
                (ClusteredSingletonColleague) singletonPoll.getTarget());
    }
}
@


1.2
log
@Refactored a lot of code to get rid of the good-looking but very slow IssueTrackingAccount{Descriptor,Map} classes. Also cleaned up the script-running interface quite a bit.
@
text
@@


1.1
log
@Added cross JVM single for denormalizing project graph database tables.
@
text
@d101 1
a101 1
        {
@

