/*
* JBoss, Home of Professional Open Source.
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* 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.jboss.varia.scheduler;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Date;
import java.util.Iterator;
import java.util.Map;
import javax.management.InstanceNotFoundException;
import javax.management.JMException;
import javax.management.MBeanException;
import javax.management.MBeanServer;
import javax.management.MBeanServerInvocationHandler;
import javax.management.MalformedObjectNameException;
import javax.management.Notification;
import javax.management.NotificationListener;
import javax.management.NotificationEmitter;
import javax.management.ObjectName;
import javax.management.timer.TimerNotification;
import javax.management.timer.TimerMBean;
import javax.management.timer.Timer;
import EDU.oswego.cs.dl.util.concurrent.SynchronizedInt;
import EDU.oswego.cs.dl.util.concurrent.SynchronizedBoolean;
import EDU.oswego.cs.dl.util.concurrent.ConcurrentReaderHashMap;
import org.jboss.logging.Logger;
import org.jboss.system.ServiceMBeanSupport;
/**
* ScheduleManager manages multiple scheduled timer listeners.
* These are registered using the {@link #addSchedule} operation.
* Providers (basically MBean lifecycle listeners) can be registered using the
* {@link #registerProvider} operation.
*
* Because of the way the JBoss deployment model works (no way to readily
* invoke operations at deployment time), prefer to use the {@link Scheduler}
* MBean instead.
*
* @author <a href="mailto:andreas@jboss.org">Andreas Schaefer</a>
* @author <a href="mailto:dimitris@jboss.org">Dimitris Andreadis</a>
* @version $Revision: 108228 $
*/
public class ScheduleManager extends ServiceMBeanSupport
implements ScheduleManagerMBean
{
// -------------------------------------------------------------------------
// Constants
// -------------------------------------------------------------------------
/**
* Default Timer Object Name
*/
public static String DEFAULT_TIMER_NAME = "jboss:service=Timer";
/**
* Counter for the number of scheduled instances.
*/
private static SynchronizedInt sCounter = new SynchronizedInt(0);
private static final int NOTIFICATION = 0;
private static final int DATE = 1;
private static final int REPETITIONS = 2;
private static final int SCHEDULER_NAME = 3;
private static final int NULL = 4;
private static final int ID = 5;
private static final int NEXT_DATE = 6;
// -------------------------------------------------------------------------
// Members
// -------------------------------------------------------------------------
private String mTimerName = DEFAULT_TIMER_NAME;
private ObjectName mTimerObjectName;
private TimerMBean mTimer;
private NotificationEmitter mTimerEmitter;
private boolean mStartOnStart = true;
private boolean mFixedRate = false;
private SynchronizedBoolean mIsPaused = new SynchronizedBoolean(false);
/**
* List of registered AbstractScheduleProvider ObjectNames to inform
* when the this manager is stop or started.
*/
private List mProviders = Collections.synchronizedList(new ArrayList());
/**
* Maps Integer to registered ScheduleInstance.
*/
private Map mSchedules = new ConcurrentReaderHashMap();
// -------------------------------------------------------------------------
// Constructors
// -------------------------------------------------------------------------
/**
* Default (no-args) Constructor
*/
public ScheduleManager()
{
}
// -------------------------------------------------------------------------
// SchedulerMBean Methods
// -------------------------------------------------------------------------
/**
* Starts all the registered Schedules
*
* @jmx:managed-operation
*/
public void startSchedules()
{
log.debug("startSchedules()");
// Check if not already started
if (!isStarted())
{
// Loop over all available Schedule Instance and start them now
Iterator i = mSchedules.values().iterator();
while (i.hasNext())
{
ScheduleInstance lInstance = (ScheduleInstance) i.next();
try
{
lInstance.start();
}
catch (JMException e)
{
log.error("Could not start: " + lInstance, e);
}
}
}
}
/**
* Stops all the registered Schedules
*
* @jmx:managed-operation
*
* @param pDoItNow If true the schedule will be stopped without waiting for the next
* scheduled call otherwise the next call will be performed before
* the schedule is stopped.
*/
public void stopSchedules(boolean pDoItNow)
{
// Check if it is already started
if (isStarted())
{
// Loop over all available Schedule Instance and start them now
Iterator i = mSchedules.values().iterator();
while (i.hasNext())
{
ScheduleInstance lInstance = (ScheduleInstance) i.next();
try
{
lInstance.stop();
}
catch (JMException e)
{
log.error("Could not stop: " + lInstance, e);
}
}
}
}
/**
* Stops existing schedules immediately and restarts them right away.
*
* @jmx:managed-operation
*/
public void restartSchedule()
{
stopSchedules(true);
startSchedules();
}
/**
* Register a Provider to make it available. In turn this
* method calls "startProviding()" method on the Provider
* to indicate that the Provider can start adding Schedules.
*
* @param pProviderObjectName Object Name of the Provider
*
* @jmx:managed-operation
*/
public void registerProvider(String pProviderObjectName)
{
try
{
registerProvider(new ObjectName(pProviderObjectName));
}
catch (JMException jme)
{
log.error("Could not call startProviding() on " + pProviderObjectName, jme);
}
}
/**
* Register a Provider to make it available. In turn this
* method calls "startProviding()" method on the Provider
* to indicate that the Provider can start adding Schedules.
*
* @param pProviderObjectName Object Name of the Provider
*
* @jmx:managed-operation
*/
public void registerProvider(ObjectName pProviderObjectName)
throws JMException
{
if (pProviderObjectName == null)
{
throw new MalformedObjectNameException("Provider must not be null");
}
synchronized (mProviders) {
if (mProviders.contains(pProviderObjectName))
throw new JMException("Already registered: " + pProviderObjectName);
mProviders.add(pProviderObjectName);
}
server.invoke(
pProviderObjectName,
"startProviding",
new Object[]{},
new String[]{}
);
}
/**
* Unregister a Provider which in turn calls "stopProviding()"
* indicating to the Provider to remove all the Schedules.
*
* @param pProviderObjectName Object Name of the Provider
*
* @jmx:managed-operation
*/
public void unregisterProvider(String pProviderObjectName)
{
try
{
unregisterProvider(new ObjectName(pProviderObjectName));
}
catch (JMException jme)
{
log.error("Could not call stopProviding() on " + pProviderObjectName, jme);
}
}
/**
* Unregister a Provider which in turn calls "stopProviding()"
* indicating to the Provider to remove all the Schedules.
*
* @param pProviderObjectName Object Name of the Provider
*
* @jmx:managed-operation
*/
public void unregisterProvider(ObjectName pProviderObjectName)
throws JMException
{
if (!mProviders.remove(pProviderObjectName))
return;
server.invoke(
pProviderObjectName,
"stopProviding",
new Object[]{},
new String[]{}
);
}
/**
* Adds a new Schedule to the Scheduler
*
* @param pTarget Object Name of the Target MBean
* @param pMethodName Name of the method to be called
* @param pMethodSignature List of Attributes of the method to be called
* where ...
* @param pStartDate Date when the schedule is started
* @param pRepetitions Initial Number of repetitions
*
* @return Identification of the Schedule used later to remove it
* if necessary
*
* @jmx:managed-operation
*/
public int addSchedule(
ObjectName pProvider,
ObjectName pTarget,
String pMethodName,
String[] pMethodSignature,
Date pStartDate,
long pPeriod,
int pRepetitions
)
{
ScheduleInstance lInstance = new ScheduleInstance(
pProvider,
pTarget,
pMethodName,
pMethodSignature,
pStartDate,
pRepetitions,
pPeriod
);
if (isStarted())
{
try
{
lInstance.start();
}
catch (JMException jme)
{
log.error("Could not start " + lInstance, jme);
}
}
int lID = lInstance.getID();
mSchedules.put(new Integer(lID), lInstance);
return lID;
}
/**
* Removes a Schedule so that no notification is sent anymore
*
* @param pIdentification Identification returned by {@link #addSchedule
* addSchedule()} or {@link #getSchedules
* getSchedules()}.
*
* @jmx:managed-operation
*/
public void removeSchedule(int pIdentification)
{
ScheduleInstance lInstance = (ScheduleInstance) mSchedules.get(new Integer(pIdentification));
try
{
if (lInstance == null)
throw new InstanceNotFoundException();
lInstance.stop();
}
catch (JMException e)
{
log.error("Could not stop " + lInstance, e);
}
mSchedules.remove(new Integer(pIdentification));
}
/**
* Returns a list of the ids of all registered schedules
*
* @return List of Ids separated by a ","
*/
public String getSchedules()
{
Iterator i = mSchedules.values().iterator();
StringBuffer lReturn = new StringBuffer();
boolean lFirst = true;
while (i.hasNext())
{
ScheduleInstance lInstance = (ScheduleInstance) i.next();
if (lFirst)
{
lReturn.append(lInstance.mIdentification);
lFirst = false;
}
else
{
lReturn.append(",").append(lInstance.mIdentification);
}
}
return lReturn.toString();
}
/**
* @return True if all the Schedules are paused meaning that even when the notifications
* are sent to the listener they are ignored. ATTENTION: this applies to all registered
* Schedules and any notifications are lost during pausing
*/
public boolean isPaused()
{
return mIsPaused.get();
}
/**
* Pauses or restarts the Schedules which either suspends the
* notifications or start transfering them to the target
*
* @param pIsPaused True when the Schedules are paused or false when they resume
*/
public void setPaused(boolean pIsPaused)
{
mIsPaused.set(pIsPaused);
}
/**
* @return true if the Schedule Manager is started
*/
public boolean isStarted()
{
return getState() == STARTED;
}
// -------------------------------------------------------------------------
// SchedulerManagerMBean Attributes
// -------------------------------------------------------------------------
/**
* Set the scheduler to start when MBean started or not. Note that this method only
* affects when the {@link #startService startService()} gets called (normally at
* startup time.
*
* @jmx:managed-attribute
*
* @param pStartAtStartup if the scheduler should be started upon MBean start or not
*/
public void setStartAtStartup(boolean pStartAtStartup)
{
mStartOnStart = pStartAtStartup;
}
/**
* @jmx:managed-attribute
*
* @return true if the scheduler should be started upon MBean start or not
*/
public boolean isStartAtStartup()
{
return mStartOnStart;
}
/**
* @jmx:managed-attribute
*
* @param pTimerName Object Name of the Timer MBean to
* be used. If null or not a valid ObjectName
* the default will be used
*/
public void setTimerName(String pTimerName)
{
mTimerName = pTimerName;
}
/**
* @jmx:managed-attribute
*
* @return Name of the Timer MBean used in here
*/
public String getTimerName()
{
return mTimerName;
}
/**
* @jmx:managed-attribute
*
* @param fixedRate the default scheduling to use, fixed-rate or fixed-delay (false, default)
*/
public void setFixedRate(boolean fixedRate)
{
mFixedRate = fixedRate;
}
/**
* @jmx:managed-attribute
*
* @return the default scheduling to use
*/
public boolean getFixedRate()
{
return mFixedRate;
}
// -------------------------------------------------------------------------
// ServiceMBeanSupport overrides
// -------------------------------------------------------------------------
public ObjectName getObjectName(MBeanServer pServer, ObjectName pName)
throws MalformedObjectNameException
{
return pName == null ? OBJECT_NAME : pName;
}
/**
* Creates the requested Timer if not already available
* and start all added Schedules.
* ATTENTION: the start of the schedules is not necessary when
* the service is started but this method is also called when
* the service is restarted and therefore schedules can be
* available.
*/
protected void startService() throws Exception
{
mTimerObjectName = new ObjectName(mTimerName);
if (!getServer().isRegistered(mTimerObjectName))
{
getServer().createMBean(Timer.class.getName(), mTimerObjectName);
}
mTimer = (TimerMBean)MBeanServerInvocationHandler.newProxyInstance(getServer(),
mTimerObjectName, TimerMBean.class, true);
mTimerEmitter = (NotificationEmitter)mTimer;
if (!mTimer.isActive())
{
mTimer.start();
}
startSchedules();
}
/**
* Stops all Schedules.
*/
protected void stopService()
{
stopSchedules(true);
}
/**
* When Service is destroyed it will call the "unregisterProvider()"
* on all register Providers to let them remove their Schedules and
* being notified that they should stop providing.
*/
protected void destroyService()
{
// Unregister all providers
Iterator i = mSchedules.values().iterator();
while (i.hasNext())
{
ScheduleInstance lInstance = (ScheduleInstance) i.next();
unregisterProvider(lInstance.mProvider.toString());
}
}
// -------------------------------------------------------------------------
// Inner Classes
// -------------------------------------------------------------------------
/**
* This listener is waiting for its Timer Notification and call the
* appropriate method on the given Target (MBean) and count down the
* number of remaining repetitions.
*/
public class MBeanListener implements NotificationListener
{
private final Logger log = Logger.getLogger(MBeanListener.class);
private ScheduleInstance mSchedule;
public MBeanListener(ScheduleInstance pSchedule)
{
mSchedule = pSchedule;
}
public void handleNotification(Notification pNotification, Object pHandback)
{
boolean trace = log.isTraceEnabled();
if (trace) {
log.trace("MBeanListener.handleNotification: " + pNotification);
}
try
{
if (!isStarted()) {
log.trace("Scheduler not started");
mSchedule.stop();
return;
}
if (mSchedule.mRemainingRepetitions == 0)
{
log.trace("No more repetitions");
mSchedule.stop();
return;
}
if (mIsPaused.get())
{
log.trace("Paused");
return;
}
if (mSchedule.mRemainingRepetitions > 0)
{
mSchedule.mRemainingRepetitions--;
if (trace)
log.trace("Remaining repetitions: " + mSchedule.mRemainingRepetitions);
}
Object[] lArguments = getArguments(pNotification);
if (trace)
{
log.trace("invoke " + mSchedule);
log.trace("arguments are: " + Arrays.asList(lArguments));
}
ObjectName on = mSchedule.mTarget;
String mn = mSchedule.mMethodName;
getServer().invoke(on, mn, lArguments,
mSchedule.mSchedulableMBeanArgumentTypes
);
}
catch (Exception e)
{
log.error("Invoke failed: " + mSchedule.getTargetString(), e);
}
}
private Object[] getArguments(Notification pNotification)
{
Object[] lArguments = new Object[mSchedule.mSchedulableMBeanArguments.length];
Date lTimeStamp = new Date(pNotification.getTimeStamp());
for (int i = 0; i < lArguments.length; i++)
{
switch (mSchedule.mSchedulableMBeanArguments[i])
{
case ID:
lArguments[i] = pNotification.getUserData();
break;
case NOTIFICATION:
lArguments[i] = pNotification;
break;
case DATE:
lArguments[i] = lTimeStamp;
break;
case REPETITIONS:
lArguments[i] = new Long(mSchedule.mRemainingRepetitions);
break;
case SCHEDULER_NAME:
lArguments[i] = getServiceName();
break;
case NEXT_DATE:
lArguments[i] = new Date(lTimeStamp.getTime() + mSchedule.mPeriod);
break;
default:
lArguments[i] = null;
}
}
return lArguments;
}
}
/**
* Filter to ensure that each Scheduler only gets notified when it is supposed to.
*/
static class IdNotificationFilter implements javax.management.NotificationFilter
{
private static final Logger log = Logger.getLogger(IdNotificationFilter.class);
private Integer filterId;
/**
* Create a Filter.
* @param pId the Scheduler id
*/
public IdNotificationFilter(int filterId)
{
this.filterId = new Integer(filterId);
}
/**
* Determine if the notification should be sent to this Scheduler
*/
public boolean isNotificationEnabled(Notification pNotification)
{
if (!(pNotification instanceof TimerNotification))
return false;
TimerNotification lTimerNotification = (TimerNotification) pNotification;
if (log.isTraceEnabled())
log.trace("isNotificationEnabled(), filterId=" + filterId +
", notification=" + pNotification +
", notificationId=" + lTimerNotification.getNotificationID() +
", timestamp=" + lTimerNotification.getTimeStamp() +
", message=" + lTimerNotification.getMessage()
);
return lTimerNotification.getNotificationID().equals(filterId);
}
}
/**
* Represents a single Schedule which can be started and stopped
* if necessary.
*/
private class ScheduleInstance
{
private final Logger log = Logger.getLogger(ScheduleInstance.class);
private int mIdentification;
private MBeanListener mListener;
public int mNotificationID;
public ObjectName mProvider;
public ObjectName mTarget;
public long mInitialRepetitions;
public long mRemainingRepetitions = 0;
public Date mStartDate;
public long mPeriod;
public String mMethodName;
public int[] mSchedulableMBeanArguments;
public String[] mSchedulableMBeanArgumentTypes;
public ScheduleInstance(
ObjectName pProvider,
ObjectName pTarget,
String pMethodName,
String[] pMethodArguments,
Date pStartDate,
int pRepetitions,
long pPeriod
)
{
mProvider = pProvider;
mTarget = pTarget;
mInitialRepetitions = pRepetitions;
mStartDate = pStartDate;
mPeriod = pPeriod;
mMethodName = pMethodName;
mSchedulableMBeanArguments = new int[pMethodArguments.length];
mSchedulableMBeanArgumentTypes = new String[pMethodArguments.length];
for (int i = 0; i < pMethodArguments.length; i++)
{
String lToken = pMethodArguments[i];
if (lToken.equals("ID"))
{
mSchedulableMBeanArguments[i] = ID;
mSchedulableMBeanArgumentTypes[i] = Integer.class.getName();
}
else if (lToken.equals("NOTIFICATION"))
{
mSchedulableMBeanArguments[i] = NOTIFICATION;
mSchedulableMBeanArgumentTypes[i] = Notification.class.getName();
}
else if (lToken.equals("NEXT_DATE"))
{
mSchedulableMBeanArguments[i] = NEXT_DATE;
mSchedulableMBeanArgumentTypes[i] = Date.class.getName();
}
else if (lToken.equals("DATE"))
{
mSchedulableMBeanArguments[i] = DATE;
mSchedulableMBeanArgumentTypes[i] = Date.class.getName();
}
else if (lToken.equals("REPETITIONS"))
{
mSchedulableMBeanArguments[i] = REPETITIONS;
mSchedulableMBeanArgumentTypes[i] = Long.TYPE.getName();
}
else if (lToken.equals("SCHEDULER_NAME"))
{
mSchedulableMBeanArguments[i] = SCHEDULER_NAME;
mSchedulableMBeanArgumentTypes[i] = ObjectName.class.getName();
}
else
{
mSchedulableMBeanArguments[i] = NULL;
//AS ToDo: maybe later to check if this class exists !
mSchedulableMBeanArgumentTypes[i] = lToken;
}
}
mIdentification = sCounter.increment();
}
/**
* Starts the Schedule by adding itself to the timer
* and registering its listener to get the notifications
* and hand over to the target
**/
public void start() throws JMException
{
Date lStartDate = null;
// Check if initial start date is in the past
if (mStartDate.getTime() < new Date().getTime() && mPeriod > 0)
{
// If then first check if a repetition is in the future
long lNow = new Date().getTime() + 100;
long lSkipRepeats = ((lNow - mStartDate.getTime()) / mPeriod) + 1;
log.debug("Old start date: " + mStartDate + ", now: " + new Date(lNow) + ", Skip repeats: " + lSkipRepeats);
if (mInitialRepetitions > 0)
{
// If not infinit loop
if (lSkipRepeats >= mInitialRepetitions)
{
// No repetition left -> exit
log.warn("No repetitions left because start date is in the past and could " +
"not be reached by Initial Repetitions * Schedule Period");
return;
}
else
{
// Reduce the missed hits
mRemainingRepetitions = mInitialRepetitions - lSkipRepeats;
}
}
else
{
if (mInitialRepetitions == 0)
{
mRemainingRepetitions = 0;
}
else
{
mRemainingRepetitions = -1;
}
}
lStartDate = new Date(mStartDate.getTime() + (lSkipRepeats * mPeriod));
}
else
{
lStartDate = mStartDate;
mRemainingRepetitions = mInitialRepetitions;
}
mNotificationID = mTimer.addNotification(
"Schedule", "Scheduler Notification",
new Integer(getID()), // User Object
lStartDate,
new Long(mPeriod),
mRemainingRepetitions < 0 ? new Long(0) : new Long(mRemainingRepetitions),
Boolean.valueOf(mFixedRate)
);
mListener = new MBeanListener(this);
mTimerEmitter.addNotificationListener(
mListener,
new IdNotificationFilter(mNotificationID),
// No object handback necessary
null
);
log.debug("start(), add Notification to Timer with ID: " + mNotificationID);
}
/**
* Stops the Schedule by remove itself from the timer
* and removing the listener
**/
public void stop()
throws JMException
{
log.debug("stopSchedule(), notification id: " + mNotificationID);
mTimerEmitter.removeNotificationListener(mListener);
try
{
mTimer.removeNotification(mNotificationID);
}
catch (InstanceNotFoundException e)
{
log.trace(e);
}
}
public int getID()
{
return mIdentification;
}
public String toString()
{
return "Schedule target=" + getTargetString();
}
public String getTargetString()
{
return mTarget + " " + mMethodName + "" + Arrays.asList(mSchedulableMBeanArgumentTypes);
}
}
}