/*
* JacORB - a free Java ORB
*
* Copyright (C) 1999-2004 Gerald Brose
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
package org.jacorb.test.notification.bugs;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jacorb.notification.AnyMessage;
import org.jacorb.notification.queue.DefaultMessageQueueAdapter;
import org.jacorb.notification.queue.BoundedFifoEventQueue;
import org.jacorb.notification.queue.EventQueueOverflowStrategy;
import org.jacorb.notification.queue.MessageQueue;
import org.jacorb.notification.queue.RWLockEventQueueDecorator;
import edu.emory.mathcs.backport.java.util.concurrent.CountDownLatch;
import edu.emory.mathcs.backport.java.util.concurrent.CyclicBarrier;
import edu.emory.mathcs.backport.java.util.concurrent.TimeUnit;
import edu.emory.mathcs.backport.java.util.concurrent.atomic.AtomicBoolean;
/**
* @author Alphonse Bendt
* @version $Id: DeadlockBugTest.java,v 1.6 2006/02/25 14:22:04 alphonse.bendt Exp $
*/
public class DeadlockBugTest extends TestCase
{
RWLockEventQueueDecorator objectUnderTest_;
Object lock_;
protected void setUp() throws Exception
{
lock_ = new Object();
MessageQueue queue = new BoundedFifoEventQueue(4, EventQueueOverflowStrategy.FIFO, lock_);
objectUnderTest_ = new RWLockEventQueueDecorator(new DefaultMessageQueueAdapter(queue));
}
/**
* Test that should provoke bug ID 544. getter thread
* needs to invoke getMessageBlocking() on an empty queue first. then second putter thread tries to
* enqueue a message into the queue which then should be returned to the first thread.
* wrong synchronization led to a deadlock.
*/
public void testDeadlock() throws Exception
{
final AnyMessage mesg = new AnyMessage();
final AtomicBoolean received = new AtomicBoolean(false);
final AtomicBoolean delivered = new AtomicBoolean(false);
final CountDownLatch threadsDone = new CountDownLatch(1);
final CountDownLatch getPutOrder = new CountDownLatch(1);
final CyclicBarrier barrier = new CyclicBarrier(2, new Runnable()
{
public void run()
{
threadsDone.countDown();
}
});
Runnable getCommand = new Runnable()
{
public void run()
{
try
{
synchronized (lock_)
{
getPutOrder.countDown();
objectUnderTest_.getMessageBlocking();
}
received.set(true);
barrier.await();
} catch (Exception e)
{
fail();
}
}
};
Runnable putCommand = new Runnable()
{
public void run()
{
try
{
getPutOrder.await();
objectUnderTest_.enqeue(mesg.getHandle());
delivered.set(true);
barrier.await();
} catch (Exception e)
{
fail();
}
}
};
Thread getter = new Thread(getCommand);
getter.setDaemon(true);
Thread putter = new Thread(putCommand);
putter.setDaemon(true);
getter.start();
putter.start();
threadsDone.await(1000, TimeUnit.MILLISECONDS);
assertTrue(delivered.get());
assertTrue(received.get());
getter.interrupt();
putter.interrupt();
}
public static Test suite()
{
return new TestSuite(DeadlockBugTest.class);
}
}