/*
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
using log4net;
using uk.co.thebadgerset.junit.extensions.ShutdownHookable;
using uk.co.thebadgerset.junit.extensions.Throttle;
namespace Apache.Qpid.Integration.Tests.framework.clocksynch
{
///
/// ClockSynchThread is a convenient utility for running a thread that periodically synchronizes the clock against
/// a reference. Supply it with a and a and it will continually keep the
/// clock up-to-date at a rate determined by the throttle.
///
///
CRC Card
///
Responsibilities
Collaborations
///
Continually sychronize the clock at a throttled rate.
///
///
public class ClockSynchThread extends Thread : ShutdownHookable
{
/// Used for debugging.
private static ILog log = LogManager.GetLogger(typeof(ClockSynchThread));
/// Holds the clock syncher for the synch thread.
private ClockSynchronizer clockSyncher;
/// Holds the throttle to limit the synch rate.
private Throttle throttle;
/// Flag to indicate that the periodic clock syncher should keep running.
bool doSynch = true;
///
/// Creates a clock synchronizer thread from a clock synchronizer and a throttle.
///
/// The clock synchronizer.
/// The throttle.
public ClockSynchThread(ClockSynchronizer syncher, Throttle throttle)
{
this.clockSyncher = syncher;
this.throttle = throttle;
}
/// Terminates the synchronization thread.
public void terminate()
{
doSynch = false;
}
/// Continually updates the clock, until is called.
public void run()
{
while (doSynch)
{
// Perform a clock clockSynch.
try
{
// Wait controlled by the throttle before doing the next synch.
throttle.throttle();
clockSyncher.synch();
log.debug("Clock synched, delta = " + clockSyncher.getDelta() + ", epsilon = " + clockSyncher.getEpsilon()
+ ".");
}
// Terminate the synch thread if the synchronization cannot be achieved.
catch (ClockSynchFailureException e)
{
log.debug("Cannot synchronize the clock (reference service may be down). Terminating the synch thread.");
doSynch = false;
}
}
}
///
/// Gets the clock synchronizer that is kept continually up to date.
///
/// The clock synchronizer that is kept continually up to date.
public ClockSynchronizer getClockSyncher()
{
return clockSyncher;
}
///
/// Supplies a shutdown hook, that terminates the synching thread.
///
/// The shut down hook.
public Thread getShutdownHook()
{
return new Thread(new Runnable()
{
public void run()
{
doSynch = false;
}
});
}
}
}