/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can obtain
* a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
* or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
* Sun designates this particular file as subject to the "Classpath" exception
* as provided by Sun in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the License
* Header, with the fields enclosed by brackets [] replaced by your own
* identifying information: "Portions Copyrighted [year]
* [name of copyright owner]"
*
* Contributor(s):
*
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package com.sun.ejb.containers;
import java.util.Date;
import java.util.Collection;
import java.util.Set;
import java.util.HashSet;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;
import java.util.TimerTask;
import java.util.Properties;
import java.util.logging.Logger;
import java.util.logging.Level;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.io.File;
import java.io.FileWriter;
import java.io.FileReader;
import java.io.BufferedWriter;
import java.io.BufferedReader;
import java.io.PrintWriter;
import java.io.File;
import java.io.Serializable;
import com.sun.logging.LogDomains;
import com.sun.ejb.ContainerFactory;
import javax.ejb.Timer;
import javax.ejb.EJBException;
import javax.ejb.FinderException;
import javax.ejb.CreateException;
import javax.ejb.RemoveException;
import com.sun.enterprise.admin.monitor.callflow.Agent;
import com.sun.enterprise.admin.monitor.callflow.RequestType;
import com.sun.enterprise.Switch;
import com.sun.enterprise.deployment.*;
import com.sun.enterprise.server.ApplicationServer;
import com.sun.enterprise.instance.InstanceEnvironment;
import com.sun.enterprise.instance.AppsManager;
import com.sun.enterprise.instance.ServerManager;
import com.sun.enterprise.config.serverbeans.ServerBeansFactory;
import com.sun.enterprise.server.ServerContext;
import com.sun.enterprise.config.serverbeans.EjbContainer;
import com.sun.enterprise.config.serverbeans.EjbTimerService;
import javax.transaction.TransactionManager;
/*
* EJBTimerService is the central controller of the EJB timer service.
* There is one instance of EJBTimerService per VM. All operations and
* state transitions on timers pass through EJB Timer Service. This
* reduces the overall complexity by encapsulating the timer logic
* within this class and keeping the supporting classes simple.
*
* @author Kenneth Saks
*/
public class EJBTimerService
implements com.sun.ejb.spi.distributed.DistributedEJBTimerService
{
private long nextTimerIdMillis_ = 0;
private long nextTimerIdCounter_ = 0;
private String serverName_;
private String domainName_;
// @@@ Double-check that the individual server id, domain name,
// and cluster name cannot contain the TIMER_ID_SEP
// characters.
// separator between components that make up timer id and owner id
private static final String TIMER_ID_SEP = "@@";
// Owner id of the server instance in which we are currently running.
private String ownerIdOfThisServer_;
// A cache of timer info for all timers *owned* by this server instance.
private TimerCache timerCache_;
private TimerLocalHome timerLocalHome_;
private TimerMigrationLocalHome timerMigrationLocalHome_;
private boolean shutdown_;
// Total number of ejb components initialized as timed objects between the
// start and end of a single server instance. This value is used during
// restoreTimers() as an optimization to avoid initialization overhead in
// the common case that there are no applications with timed objects.
// It is NOT intended to be a consistent count of the current number of
// timed objects, so there is no need to decrement the number when a
// container is undeployed.
private long totalTimedObjectsInitialized_ = 0;
private static final Logger logger =
LogDomains.getLogger(LogDomains.EJB_LOGGER);
// Defaults for configurable timer service properties.
private static final long MINIMUM_DELIVERY_INTERVAL = 7000;
private static final int MAX_REDELIVERIES = 1;
private static final long REDELIVERY_INTERVAL = 5000;
private String appID;
// minimum amount of time between either a timer creation and its first
// expiration or between subsequent timer expirations.
private long minimumDeliveryInterval_ = MINIMUM_DELIVERY_INTERVAL;
// maximum number of times the container will attempt to retry a
// timer delivery before giving up.
private long maxRedeliveries_ = MAX_REDELIVERIES;
// amount of time the container waits between timer redelivery attempts.
private long redeliveryInterval_ = REDELIVERY_INTERVAL;
private static final String TIMER_SERVICE_FILE =
"__timer_service_shutdown__.dat";
private static final String TIMER_SERVICE_DOWNTIME_FORMAT =
"yyyy/MM/dd HH:mm:ss";
// This boolean value would be set in PE to be a default value of false.
// In case of EE the default value would be true. When set to true the
// timer service would have maximim consistency with performance degration.
private boolean performDBReadBeforeTimeout = false;
private static final String strDBReadBeforeTimeout =
"com.sun.ejb.timer.ReadDBBeforeTimeout";
private boolean foundSysPropDBReadBeforeTimeout = false;
public EJBTimerService(String appID, TimerLocalHome timerLocalHome,
TimerMigrationLocalHome timerMigrationLocalHome)
{
timerLocalHome_ = timerLocalHome;
timerMigrationLocalHome_ = timerMigrationLocalHome;
timerCache_ = new TimerCache();
shutdown_ = false;
this.appID = appID;
domainName_ = ServerManager.instance().getDomainName();
InstanceEnvironment server =
ApplicationServer.getServerContext().getInstanceEnvironment();
serverName_ = server.getName();
initProperties();
}
private void initProperties() {
try {
// Check for property settings from domain.xml
ServerContext sc = ApplicationServer.getServerContext();
EjbContainer ejbc = ServerBeansFactory.
getConfigBean(sc.getConfigContext()).getEjbContainer();
EjbTimerService ejbt = ejbc.getEjbTimerService();
if( ejbt != null ) {
String valString = ejbt.getMinimumDeliveryIntervalInMillis();
long val = (valString != null) ?
Long.parseLong(valString) : -1;
if( val > 0 ) {
minimumDeliveryInterval_ = val;
}
valString = ejbt.getMaxRedeliveries();
val = (valString != null) ? Long.parseLong(valString) : -1;
// EJB 2.1 specification minimum is 1
if( val > 0 ) {
maxRedeliveries_ = val;
}
valString = ejbt.getRedeliveryIntervalInternalInMillis();
val = (valString != null) ? Long.parseLong(valString) : -1;
if( val > 0 ) {
redeliveryInterval_ = val;
}
// If the system property com.sun.ejb.timer.ReadDBBeforeTimeout
// is defined by the user use that the value of the flag
// performDBReadBeforeTimeout
foundSysPropDBReadBeforeTimeout =
getDBReadBeforeTimeoutProperty();
// The default value for ReadDBBeforeTimeout in case of PE
// is false. For SE/EE the correct default would set when the
// EJBLifecyleImpl gets created as part of the EE lifecycle module
setPerformDBReadBeforeTimeout( false );
}
// Compose owner id for all timers created with this
// server instance.
InstanceEnvironment server = sc.getInstanceEnvironment();
String serverName = server.getName();
ownerIdOfThisServer_ = serverName;
} catch(Exception e) {
logger.log(Level.FINE, "Exception converting timer service " +
"domain.xml properties. Defaults will be used instead.", e);
}
logger.log(Level.FINE, "EJB Timer Service properties : " +
"min delivery interval = " + minimumDeliveryInterval_ +
"\nmax redeliveries = " + maxRedeliveries_ +
"\nredelivery interval = " + redeliveryInterval_);
}
synchronized void timedObjectCount() {
totalTimedObjectsInitialized_++;
}
/**
* Return the ownerId of the server instance in
* which we are running.
*/
String getOwnerIdOfThisServer() {
return ownerIdOfThisServer_;
}
/**
*--------------------------------------------------------------
* Methods to be implemented for DistributedEJBTimerService
*--------------------------------------------------------------
*/
/**
* Create EJBException using the exception that is passed in
*/
private EJBException createEJBException( Exception ex ) {
EJBException ejbEx = new EJBException();
ejbEx.initCause(ex);
return ejbEx;
}
/**
* Provide a count of timers owned by each server
*/
public String[] listTimers( String[] serverIds ) {
String[] totalTimers = new String[ serverIds.length ];
try {
for ( int i = 0; i < serverIds.length; i++ ) {
totalTimers[i] = new String(
new Integer(
timerLocalHome_.selectCountAllTimersOwnedBy(
serverIds[i] )).toString());
}
} catch( Exception ex ) {
logger.log( Level.SEVERE, "Exception in listTimers() : " , ex );
//Propogate any exceptions caught
EJBException ejbEx = createEJBException( ex );
throw ejbEx;
}
return totalTimers;
}
/**
* Take ownership of another server's timers.
*/
public int migrateTimers(String fromOwnerId) {
String ownerIdOfThisServer = getOwnerIdOfThisServer();
if( fromOwnerId.equals(ownerIdOfThisServer) ) {
/// Error. The server from which timers are being
// migrated should never be up and running OR receive this
// notification.
logger.log(Level.WARNING, "Attempt to migrate timers from " +
"an active server instance " + ownerIdOfThisServer);
throw new IllegalStateException("Attempt to migrate timers from " +
" an active server instance " +
ownerIdOfThisServer);
}
logger.log(Level.INFO, "Beginning timer migration process from " +
"owner " + fromOwnerId + " to " + ownerIdOfThisServer);
TransactionManager tm = Switch.getSwitch().getTransactionManager();
Set toRestore = new HashSet();
try {
tm.begin();
// The timer objects we'll use to set the new owner id come
// from TimerMigrationBean
Set toMigrate = timerMigrationLocalHome_.
selectAllTimersOwnedBy(fromOwnerId);
// The timer objects we'll use for restoring come from TimerBean
// The same EJB QL query is used for selectAllTimersOwnedBy(owner)
toRestore = timerLocalHome_.
selectAllTimersOwnedBy(fromOwnerId);
for(Iterator iter = toMigrate.iterator(); iter.hasNext();) {
TimerMigrationLocal next = (TimerMigrationLocal) iter.next();
next.setOwnerId(ownerIdOfThisServer);
}
tm.commit();
} catch(Exception e) {
// Don't attempt to restore any timers since an error has
// occurred. This could be the expected result in the case that
// multiple server instances attempted the migration at the same
// time.
//FindBugs [Deadstore]: toRestore = new HashSet();
logger.log(Level.FINE, "timer migration error", e);
try {
tm.rollback();
} catch(Exception re) {
logger.log(Level.FINE, "timer migration rollback error", re);
}
//Propagate the exception caught
EJBException ejbEx = createEJBException( e );
throw ejbEx;
}
int totalTimersMigrated = toRestore.size();
if( toRestore.size() > 0 ) {
boolean success = false;
try {
logger.log(Level.INFO, "Timer migration phase 1 complete. " +
"Changed ownership of " + toRestore.size() +
" timers. Now reactivating timers...");
tm.begin();
_restoreTimers(toRestore);
success = true;
} catch(Exception e) {
logger.log(Level.FINE, "timer restoration error", e);
//Propogate any exceptions caught as part of the transaction
EJBException ejbEx = createEJBException( e );
throw ejbEx;
} finally {
// We're not modifying any state in this tx so no harm in
// always committing.
try {
tm.commit();
} catch(Exception re) {
logger.log(Level.FINE, "timer migration error", re);
if( success ) {
//Propogate any exceptions caught when trying to commit
//the transaction
EJBException ejbEx = createEJBException( re );
throw ejbEx;
}
}
}
} else {
logger.log(Level.INFO, fromOwnerId + " has 0 timers in need " +
"of migration");
}
return totalTimersMigrated;
} //migrateTimers()
public void setPerformDBReadBeforeTimeout( boolean defaultDBReadValue ) {
// If the system property com.sun.ejb.timer.ReadDBBeforeTimeout
// has been defined by the user then use that value else use the default
if ( !foundSysPropDBReadBeforeTimeout ) {
performDBReadBeforeTimeout = defaultDBReadValue;
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "EJB Timer Service property : " +
"\nread DB before timeout delivery = " +
performDBReadBeforeTimeout);
}
}
}
/**
* Check to see if the user has defined a System property to specify if
* we need to check the timer table in the database and confirm that the
* timer is valid before delivering the ejbTimeout() for that timer.
*
* In case of PE - the default value is false
* and for SE/EE - the default value is true
*
* But in all cases (PE/SE/EE) the user can set the System property
* "READ_DB_BEFORE_EJBTIMEOUT" to change the behaviour
*/
private boolean getDBReadBeforeTimeoutProperty() {
boolean result = false;
try{
Properties props = System.getProperties();
String str=props.getProperty( strDBReadBeforeTimeout );
if( null != str) {
str = str.toLowerCase();
performDBReadBeforeTimeout = Boolean.valueOf(str).booleanValue();
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "EJB Timer Service property : " +
"\nread DB before timeout delivery = " +
performDBReadBeforeTimeout);
}
result = true;
}
} catch(Exception e) {
logger.log(Level.INFO,
"ContainerFactoryImpl.getDebugMonitoringDetails(), " +
" Exception when trying to " +
"get the System properties - ", e);
}
return result;
}
/**
* Called at server startup *after* user apps have been re-activated
* to restart any active EJB timers.
*/
void restoreTimers() throws Exception {
// Optimization. Skip timer restoration if there aren't any
// applications with timed objects deployed.
if( totalTimedObjectsInitialized_ == 0 ) {
return;
}
TransactionManager tm = Switch.getSwitch().getTransactionManager();
Set allActiveTimers = new HashSet();
try {
// create a tx in which to do database access for all timers
// needing restoration. This gives us better performance that
// doing individual transactions per timer.
tm.begin();
// This operation can take a while, since in some configurations
// this will be the first time the connection to the database
// is initialized. In addition, there's an initialization
// cost to generating the SQL for the underlying
// ejbql queries the first time any TimerBean query is called.
allActiveTimers =
timerLocalHome_.selectAllActiveTimersOwnedByThisServer();
_restoreTimers(allActiveTimers);
} catch(Exception e) {
// Problem accessing timer service so disable it.
ContainerFactoryImpl cf = (ContainerFactoryImpl)
Switch.getSwitch().getContainerFactory();
cf.setEJBTimerService(null);
logger.log(Level.WARNING, "ejb.timer_service_init_error", e);
// No need to propagate exception. EJB Timer Service is disabled
// but that won't affect the rest of the EJB container services.
return;
} finally {
// try to commit regardless of success or failure.
try {
tm.commit();
} catch(Exception e) {
logger.log(Level.WARNING, "ejb.timer_service_init_error", e);
}
}
}
/**
* The portion of timer restoration that deals with registering the
* JDK timer tasks and checking for missed expirations.
*/
private void _restoreTimers(Set timersEligibleForRestoration) {
// Do timer restoration in two passes. The first pass updates
// the timer cache with each timer. The second pass schedules
// the JDK timer tasks.
Map timersToRestore = new HashMap();
for(Iterator iter = timersEligibleForRestoration.iterator();
iter.hasNext();) {
TimerLocal next = (TimerLocal) iter.next();
long containerId = next.getContainerId();
// Timer might refer to an obsolete container.
BaseContainer container = getContainer(containerId);
if( container != null ) {
TimerPrimaryKey timerId = (TimerPrimaryKey)next.getPrimaryKey();
Date initialExpiration = next.getInitialExpiration();
// Create an instance of RuntimeTimerState.
// Only access timedObjectPrimaryKey if timed object is
// an entity bean. That allows us to lazily load the underlying
// blob for stateless session and message-driven bean timers.
Object timedObjectPrimaryKey = null;
if( container instanceof EntityContainer ) {
timedObjectPrimaryKey = next.getTimedObjectPrimaryKey();
}
RuntimeTimerState timerState = new RuntimeTimerState
(timerId, initialExpiration,
next.getIntervalDuration(), container,
timedObjectPrimaryKey);
timerCache_.addTimer(timerId, timerState);
// If a single-action timer is still in the database it never
// successfully delivered, so always reschedule a timer task
// for it. For periodic timers, we use the last known
// expiration time to decide whether we need to fire one
// ejbTimeout to make up for any missed ones.
Date expirationTime = initialExpiration;
Date now = new Date();
if( timerState.isPeriodic() ) {
// lastExpiration time, or null if we either aren't
// tracking last expiration or an expiration hasn't
// occurred yet for this timer.
Date lastExpiration = next.getLastExpiration();
// @@@ need to handle case where last expiration time
// is not stored in database. This will be the case
// when we add configuration for update-db-on-delivery.
// However, for now assume we do update the db on each
// ejbTimeout. Therefore, if (lastExpirationTime == null),
// it means the timer didn't successfully complete any
// timer expirations.
if( (lastExpiration == null) &&
now.after(initialExpiration) ) {
// This timer didn't even expire one time.
logger.log(Level.INFO,
"Rescheduling missed expiration for " +
"periodic timer " +
timerState + ". Timer expirations should " +
" have been delivered starting at " +
initialExpiration);
// keep expiration time at initialExpiration. That
// will force an ejbTimeout almost immediately. After
// that the timer will return to fixed rate expiration.
} else if ( (lastExpiration != null) &&
( (now.getTime() - lastExpiration.getTime()
> next.getIntervalDuration()) ) ) {
logger.log(Level.INFO,
"Rescheduling missed expiration for " +
"periodic timer " +
timerState + ". Last timer expiration " +
"occurred at " + lastExpiration);
// Timer expired at least once and at least one
// missed expiration has occurred.
// keep expiration time at initialExpiration. That
// will force an ejbTimeout almost immediately. After
// that the timer will return to fixed rate expiration.
} else {
// In this case, at least one expiration has occurred
// but that was less than one period ago so there were
// no missed expirations.
expirationTime =
calcNextFixedRateExpiration(timerState);
}
} else { // single-action timer
if( now.after(initialExpiration) ) {
logger.log(Level.INFO,
"Rescheduling missed expiration for " +
"single-action timer " +
timerState + ". Timer expiration should " +
" have been delivered at " +
initialExpiration);
}
}
timersToRestore.put(timerState, expirationTime);
} else {
// Timed object's container no longer exists.
try {
next.remove();
} catch(RemoveException e) {
logger.log(Level.FINE,
"Removing timer " + next.getPrimaryKey() +
" for unknown container " + containerId, e);
}
}
} // End -- for each active timer
for(Iterator entries = timersToRestore.entrySet().iterator();
entries.hasNext(); ) {
Map.Entry next = (Map.Entry) entries.next();
RuntimeTimerState nextTimer = (RuntimeTimerState) next.getKey();
TimerPrimaryKey timerId = nextTimer.getTimerId();
Date expiration = (Date) next.getValue();
scheduleTask(timerId, expiration);
logger.log(Level.FINE,
"EJBTimerService.restoreTimers(), scheduling timer " +
nextTimer);
}
logger.log(Level.FINE, "DONE EJBTimerService.restoreTimers()");
}
void shutdown() {
// Set flag to prevent any new timer expirations.
shutdown_ = true;
}
/**
* Cancel all timers associated with a particular entity bean
* identity. This is typically called when an entity bean is
* removed. Note that this action falls under the normal EJB
* Timer removal semantics, which means it can be rolled back
* if the transaction rolls back.
*/
void cancelEntityBeanTimers(long containerId, Object primaryKey) {
try {
// Get *all* timers for this entity bean identity. This includes
// even timers *not* owned by this server instance, but that
// are associated with the same entity bean and primary key.
Collection timers = getTimers(containerId, primaryKey);
if( logger.isLoggable(Level.FINE) ) {
if( timers.isEmpty() ) {
logger.log(Level.FINE, "0 cancelEntityBeanTimers for " +
containerId + ", " + primaryKey);
}
}
for(Iterator iter = timers.iterator(); iter.hasNext();) {
TimerLocal next = (TimerLocal) iter.next();
try {
cancelTimer(next);
} catch(Exception e) {
logger.log(Level.WARNING, "ejb.cancel_entity_timer",
new Object[] { next.getPrimaryKey() });
logger.log(Level.WARNING, "", e);
}
}
} catch(Exception e) {
logger.log(Level.WARNING, "ejb.cancel_entity_timers",
new Object[] { new Long(containerId), primaryKey });
logger.log(Level.WARNING, "", e);
}
}
/**
* Destroy all timers associated with a particular ejb container
* and owned by this server instance.
* This is typically called when an ejb is undeployed. It expunges
* all timers whose timed object matches the given container. In
* the case of an entity bean container, all timers associated with
* any of that container's entity bean identities will be destroyed.
* This action *can not* be rolled back.
*/
void destroyTimers(long containerId) {
Set timers = null;
TransactionManager tm = Switch.getSwitch().getTransactionManager();
try {
// create a tx in which to do database access for all timers
// that need to be deleted. This gives us better performance that
// doing individual transactions per timer.
tm.begin();
// Get *all* timers for this ejb. Since the app is being undeployed
// any server instance can delete all the timers for the same ejb.
// Whichever one gets there first will actually do the delete.
timers = timerLocalHome_.selectTimersByContainer(containerId);
for(Iterator iter = timers.iterator(); iter.hasNext();) {
TimerLocal next = (TimerLocal) iter.next();
TimerPrimaryKey nextTimerId = null;
RuntimeTimerState nextTimerState = null;
try {
nextTimerId = (TimerPrimaryKey) next.getPrimaryKey();
nextTimerState = getTimerState(nextTimerId);
if( nextTimerState != null ) {
synchronized(nextTimerState) {
if( nextTimerState.isScheduled() ) {
EJBTimerTask timerTask =
nextTimerState.getCurrentTimerTask();
timerTask.cancel();
}
}
}
next.remove();
} catch(Exception e) {
logger.log(Level.WARNING, "ejb.destroy_timer_error",
new Object[] { nextTimerId });
logger.log(Level.WARNING, "", e);
} finally {
if( nextTimerState != null ) {
timerCache_.removeTimer(nextTimerId);
}
}
}
} catch(Exception ex) {
logger.log(Level.WARNING, "destroy_timers_error",
new Object[] { new Long(containerId) });
logger.log(Level.WARNING, "", ex);
return;
} finally {
try {
tm.commit();
} catch(Exception e) {
// Most likely caused by two or more server instances trying
// to delete the timers for the same ejb at the same time.
logger.log(Level.WARNING, "destroy_timers_error",
new Object[] { new Long(containerId) });
logger.log(Level.WARNING, "", e);
}
}
return;
}
void rescheduleTask(TimerPrimaryKey timerId, Date expiration) {
scheduleTask(timerId, expiration, true);
}
void scheduleTask(TimerPrimaryKey timerId, Date expiration) {
scheduleTask(timerId, expiration, false);
}
void scheduleTask(TimerPrimaryKey timerId, Date expiration,
boolean rescheduled) {
RuntimeTimerState timerState = getTimerState(timerId);
if( timerState != null ) {
synchronized(timerState) {
Date timerExpiration = expiration;
if( !rescheduled ) {
// Guard against very small timer intervals. The EJB Timer
// service is defined in units of milliseconds, but it is
// intended for coarse-grained events. Very small timer
// intervals (e.g. 1 millisecond) are likely to overload
// the server, so compensate by adjusting to a configurable
// minimum interval.
Date cutoff = new Date(new Date().getTime() +
getMinimumDeliveryInterval());
if( expiration.before(cutoff) ) {
timerExpiration = cutoff;
}
}
EJBTimerTask timerTask =
new EJBTimerTask(timerExpiration, timerId, this);
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, (rescheduled ? "RE-" : "") +
"Scheduling " + timerState +
" for timeout at " + timerExpiration);
}
if( rescheduled ) {
timerState.rescheduled(timerTask);
} else {
timerState.scheduled(timerTask);
}
java.util.Timer jdkTimer = Switch.getSwitch().getTimer();
jdkTimer.schedule(timerTask, timerExpiration);
}
} else {
logger.log(Level.FINE, "No timer state found for " +
(rescheduled ? "RE-schedule" : "schedule") +
" request of " + timerId +
" for timeout at " + expiration);
}
}
/**
* Called from TimerBean to cancel the next scheduled expiration
* for a timer.
* @return (initialExpiration time) if state is CREATED or
* (time that expiration would have occurred) if state=SCHEDULED or
* (null) if state is BEING_DELIVERED or timer id not found
*/
Date cancelTask(TimerPrimaryKey timerId) {
Date timeout = null;
RuntimeTimerState timerState = getTimerState(timerId);
if( timerState != null ) {
synchronized(timerState) {
if( timerState.isCreated() ) {
timeout = timerState.getInitialExpiration();
} else if( timerState.isScheduled() ) {
EJBTimerTask timerTask = timerState.getCurrentTimerTask();
timeout = timerTask.getTimeout();
timerTask.cancel();
}
timerState.cancelled();
}
} else {
logger.log(Level.FINE, "No timer state found for " +
"cancelTask request of " + timerId);
}
return timeout;
}
/**
* Called from TimerBean in case where Timer is cancelled from within
* its own ejbTimeout method and then rolled back.
*/
void restoreTaskToDelivered(TimerPrimaryKey timerId) {
RuntimeTimerState timerState = getTimerState(timerId);
if( timerState != null ) {
synchronized(timerState) {
timerState.restoredToDelivered();
}
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "Restoring " + timerId +
" to delivered state after it was cancelled and " +
" rolled back from within its own ejbTimeout method");
}
} else {
logger.log(Level.FINE, "No timer state found for " +
"restoreTaskToDelivered request of " + timerId);
}
}
void expungeTimer(TimerPrimaryKey timerId) {
// Expunge timer from timer cache without removing timer associated
// timer bean.
expungeTimer(timerId, false);
}
private Date calcInitialFixedRateExpiration(long timerServiceWentDownAt,
RuntimeTimerState timerState)
{
if (!timerState.isPeriodic()) {
throw new IllegalStateException();
}
Date now = new Date();
long nowMillis = now.getTime();
long initialExpiration = timerState.getInitialExpiration().getTime();
long now2initialDiff = nowMillis - initialExpiration;
long count = now2initialDiff / timerState.getIntervalDuration();
long previousExpiration =
initialExpiration + (count * timerState.getIntervalDuration());
if ((previousExpiration >= timerServiceWentDownAt)
&& (previousExpiration <= nowMillis))
{
//We certainly missed this one while the server was down
logger.log(Level.INFO, "ejb.deliver_missed_timer",
new Object[] { timerState.getTimerId(),
new Date(previousExpiration) });
return now;
} else {
//Calculate the new expiration time
return calcNextFixedRateExpiration(timerState);
}
}
private Date calcNextFixedRateExpiration(RuntimeTimerState timerState) {
if( !timerState.isPeriodic() ) {
throw new IllegalStateException("Timer " + timerState + " is " +
"not a periodic timer");
}
Date initialExpiration = timerState.getInitialExpiration();
long intervalDuration = timerState.getIntervalDuration();
return calcNextFixedRateExpiration(initialExpiration, intervalDuration);
}
private Date calcNextFixedRateExpiration(Date initialExpiration,
long intervalDuration) {
Date now = new Date();
long nowMillis = now.getTime();
// In simplest case, initial expiration hasn't even occurred yet.
Date nextExpirationTime = initialExpiration;
if( now.after(initialExpiration) ) {
long timeSinceInitialExpire =
(nowMillis - initialExpiration.getTime());
// number of time intervals since initial expiration.
// intervalDuration is guaranteed to be >0 since this is a
// periodic timer.
long numIntervals =
(timeSinceInitialExpire / intervalDuration);
// Increment the number of intervals and multiply by the interval
// duration to calculate the next fixed-rate boundary.
nextExpirationTime = new Date(initialExpiration.getTime() +
((numIntervals + 1) * intervalDuration));
}
return nextExpirationTime;
}
/**
* Remove all traces of a timer. This should be written defensively
* so that if expunge is called multiple times for the same timer id,
* the second, third, fourth, etc. calls will not cause exceptions.
*/
private void expungeTimer(TimerPrimaryKey timerId,
boolean removeTimerBean) {
// First remove timer bean. Don't update cache until
// afterwards, since accessing of timer bean might require
// access to timer state(e.g. timer application classloader)
if( removeTimerBean ) {
removeTimerBean(timerId);
}
timerCache_.removeTimer(timerId);
}
/**
* @param primaryKey can be null if timed object is not an entity bean.
* @return Primary key of newly created timer
*/
TimerPrimaryKey createTimer(long containerId, Object timedObjectPrimaryKey,
long initialDuration, long intervalDuration,
Serializable info) throws CreateException {
Date now = new Date();
Date initialExpiration = new Date(now.getTime() + initialDuration);
return createTimer(containerId, timedObjectPrimaryKey,
initialExpiration, intervalDuration, info);
}
/**
* @param primaryKey can be null if timed object is not an entity bean.
* @return Primary key of newly created timer
*/
TimerPrimaryKey createTimer(long containerId, Object timedObjectPrimaryKey,
Date initialExpiration, long intervalDuration,
Serializable info) throws CreateException {
BaseContainer container = getContainer(containerId);
if( container == null ) {
throw new CreateException("invalid container id " + containerId +
" in createTimer request");
}
Class ejbClass = container.getEJBClass();
if( !container.isTimedObject() ) {
throw new CreateException
("Attempt to create an EJB Timer from a bean that is " +
"not a Timed Object. EJB class " + ejbClass +
" must implement javax.ejb.TimedObject or " +
" annotation a timeout method with @Timeout");
}
TimerPrimaryKey timerId = new TimerPrimaryKey(getNextTimerId());
RuntimeTimerState timerState =
new RuntimeTimerState(timerId, initialExpiration,
intervalDuration, container,
timedObjectPrimaryKey);
synchronized(timerState) {
// Add timer entry before calling TimerBean.create, since
// create() actions might call back on EJBTimerService and
// need access to timer cache.
timerCache_.addTimer(timerId, timerState);
try {
timerLocalHome_.create(timerId.getTimerId(), containerId,
ownerIdOfThisServer_,
timedObjectPrimaryKey,
initialExpiration, intervalDuration,
info);
} catch(Exception e) {
logger.log(Level.SEVERE, "ejb.create_timer_failure",
new Object[] { new Long(containerId),
timedObjectPrimaryKey,
info });
logger.log(Level.SEVERE, "", e);
// Since timer was never created, remove it from cache.
timerCache_.removeTimer(timerId);
if( e instanceof CreateException ) {
throw ((CreateException)e);
} else {
EJBException ejbEx = new EJBException();
ejbEx.initCause(e);
throw ejbEx;
}
}
}
return timerId;
}
/**
* Use database query to retrieve all active timers. Results must
* be transactionally consistent. E.g., a client calling
* getTimers within a transaction where a timer has been
* created but not committed "sees" the timer but a client
* in a different transaction doesn't.
*
* @param primaryKey can be null if not entity bean
*
* @return Collection of TimerLocal objects.
*/
private Collection getTimers(long containerId,
Object timedObjectPrimaryKey)
throws FinderException {
// The results should include all timers for the given ejb
// and/or primary key, including timers owned by other server instances.
// @@@ Might want to consider cases where we can use
// timer cache to avoid some database access in PE/SE, or
// even in EE with the appropriate consistency tradeoff.
Collection activeTimers =
timerLocalHome_.selectActiveTimersByContainer(containerId);
Collection timersForTimedObject = activeTimers;
if( timedObjectPrimaryKey != null ) {
// Database query itself can't do equality check on primary
// key of timed object so perform check ourselves.
timersForTimedObject = new HashSet();
for(Iterator iter = activeTimers.iterator(); iter.hasNext();) {
TimerLocal next = (TimerLocal) iter.next();
Object nextTimedObjectPrimaryKey =
next.getTimedObjectPrimaryKey();
if( nextTimedObjectPrimaryKey.equals(timedObjectPrimaryKey) ) {
timersForTimedObject.add(next);
}
}
}
return timersForTimedObject;
}
/**
* Use database query to retrieve the timer ids of all active
* timers. Results must be transactionally consistent. E.g.,
* a client calling getTimerIds within a transaction where a
* timer has been created but not committed "sees" the timer
* but a client in a different transaction doesn't. Called by
* EJBTimerServiceWrapper when caller calls getTimers.
*
* @param primaryKey can be null if not entity bean
* @return Collection of Timer Ids.
*/
Collection getTimerIds(long containerId, Object timedObjectPrimaryKey)
throws FinderException {
// The results should include all timers for the given ejb
// and/or primary key, including timers owned by other server instances.
// @@@ Might want to consider cases where we can use
// timer cache to avoid some database access in PE/SE, or
// even in EE with the appropriate consistency tradeoff.
Collection timerIdsForTimedObject = new HashSet();
if( timedObjectPrimaryKey == null ) {
timerIdsForTimedObject =
timerLocalHome_.selectActiveTimerIdsByContainer(containerId);
} else {
// Database query itself can't do equality check on primary
// key of timed object so perform check ourselves.
Collection timersForTimedObject = getTimers(containerId,
timedObjectPrimaryKey);
timerIdsForTimedObject = new HashSet();
for(Iterator iter = timersForTimedObject.iterator();
iter.hasNext();) {
TimerLocal next = (TimerLocal) iter.next();
timerIdsForTimedObject.add(next.getPrimaryKey());
}
}
return timerIdsForTimedObject;
}
/**
* Get the application class loader for the timed object
* that created a given timer.
*/
ClassLoader getTimerClassLoader(long containerId) {
BaseContainer container = getContainer(containerId);
return (container != null) ? container.getClassLoader() : null;
}
TimerLocalHome getTimerBeanHome() {
return timerLocalHome_;
}
private RuntimeTimerState getTimerState(TimerPrimaryKey timerId) {
return timerCache_.getTimerState(timerId);
}
private TimerLocal findTimer(TimerPrimaryKey timerId)
throws FinderException {
return timerLocalHome_.findByPrimaryKey(timerId);
}
//
// Logic used by TimerWrapper for javax.ejb.Timer methods.
//
void cancelTimer(TimerPrimaryKey timerId)
throws FinderException, Exception {
// @@@ We can't assume this server instance owns the timer
// so always ask the database. Investigate possible use of
// timer cache for optimization.
// Look up timer bean from database. Throws FinderException if
// timer no longer exists.
TimerLocal timerBean = findTimer(timerId);
cancelTimer(timerBean);
}
private void cancelTimer(TimerLocal timerBean) throws Exception {
if( timerBean.isCancelled() ) {
// Already cancelled within this tx. Nothing more to do.
} else {
timerBean.cancel();
timerBean.remove();
}
}
/**
* Return next planned timeout for this timer. We have a fair amount
* of leeway regarding the consistency of this information. We should
* strive to detect the case where the timer no longer exists. However,
* since the current timer instance may not even own this timer,
* it's difficult to know the exact time of delivery in another server
* instance. In the case of single-action timers, we return the
* expiration time that was provided upon timer creation. For
* periodic timers, we can derive the next scheduled fixed rate
* expiration based on the initial expiration and the interval.
*/
Date getNextTimeout(TimerPrimaryKey timerId) throws FinderException {
// @@@ We can't assume this server instance owns the timer
// so always ask the database. Investigate possible use of
// timer cache for optimization.
TimerLocal timerBean = findTimer(timerId);
if( timerBean.isCancelled() ) {
// The timer has been cancelled within this tx.
throw new FinderException("timer " + timerId + " does not exist");
}
Date initialExpiration = timerBean.getInitialExpiration();
Date nextTimeout = timerBean.repeats() ?
calcNextFixedRateExpiration(initialExpiration,
timerBean.getIntervalDuration()) :
initialExpiration;
return nextTimeout;
}
Serializable getInfo(TimerPrimaryKey timerId) throws FinderException {
// @@@ We can't assume this server instance owns the timer
// so always ask the database. Investigate possible use of
// timer cache for optimization.
TimerLocal timerBean = findTimer(timerId);
if( timerBean.isCancelled() ) {
// The timer has been cancelled within this tx.
throw new FinderException("timer " + timerId + " does not exist");
}
return timerBean.getInfo();
}
boolean timerExists(TimerPrimaryKey timerId) {
boolean exists = false;
// @@@ We can't assume this server instance owns the timer
// so always ask the database. Investigate possible use of
// timer cache for optimization.
try {
TimerLocal timerBean = findTimer(timerId);
// Make sure timer hasn't been cancelled within the current tx.
exists = timerBean.isActive();
} catch(FinderException fe) {
exists = false;
}
return exists;
}
private void removeTimerBean(TimerPrimaryKey timerId) {
try {
TimerLocal timerBean = findTimer(timerId);
timerBean.remove();
} catch(Throwable t) {
logger.log(Level.WARNING, "ejb.remove_timer_failure",
new Object[] { timerId });
logger.log(Level.WARNING, "", t);
}
}
private BaseContainer getContainer(long containerId) {
ContainerFactory cf = Switch.getSwitch().getContainerFactory();
return (BaseContainer) cf.getContainer(containerId);
}
/**
* Called from timer thread. Used to deliver ejb timeout.
*/
private void deliverTimeout(TimerPrimaryKey timerId) {
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "EJBTimerService.deliverTimeout(): work "
+
"thread is processing work for timerId = " + timerId);
}
if( shutdown_ ) {
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "Cancelling timeout for " + timerId +
" due to server shutdown. Expiration " +
" will occur when server is restarted.");
}
return;
}
RuntimeTimerState timerState = getTimerState(timerId);
//
// Make some defensive state checks. It's possible that the
// timer state changed between the time that the JDK timer task expired
// and we got called on this thread.
//
if( timerState == null ) {
logger.log(Level.FINE, "Timer state is NULL for timer " + timerId +
" in deliverTimeout");
return;
}
BaseContainer container = getContainer(timerState.getContainerId());
synchronized(timerState) {
if( container == null ) {
logger.log(Level.FINE, "Unknown container for timer " +
timerId + " in deliverTimeout. Expunging timer.");
expungeTimer(timerId, true);
return;
} else if ( !timerState.isBeingDelivered() ) {
logger.log(Level.FINE, "Timer state = " +
timerState.stateToString() +
"for timer " + timerId + " before callEJBTimeout");
return;
} else {
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "Calling ejbTimeout for timer " +
timerState);
}
}
}
try {
Switch.getSwitch().getCallFlowAgent().
requestStart(RequestType.TIMER_EJB);
container.onEnteringContainer();
// Need to address the case that another server instance
// cancelled this timer. For maximum consistency, we will need
// to do a database read before each delivery. This can have
// significant performance implications, so investigate possible
// reduced consistency tradeoffs.
if( performDBReadBeforeTimeout) {
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "For Timer :" + timerId +
": check the database to ensure that the timer is still " +
" valid, before delivering the ejbTimeout call" );
}
if( ! checkForTimerValidity(timerId) ) {
// The timer for which a ejbTimeout is about to be delivered
// is not present in the database. This could happen in the
// SE/EE case as other server instances (other than the owner)
// could call a cancel on the timer - deleting the timer from
// the database.
// Also it is possible that the timer is now owned by some other
// server instance
return;
}
}
///
// Call container to invoke ejbTimeout on the bean instance.
// The remaining actions are divided up into two categories :
//
// 1) Actions that should be done within the same transaction
// context as the ejbTimeout call itself. These are
// handled by having the ejb container call back on the
// postEjbTimeout method after it has invoked bean.ejbTimeout
// but *before* it has called postInvoke. That way any
// transactional operations like setting the last update time
// for periodic timers or removing a successfully delivered
// single-action timer can be done within the same tx as
// the ejbTimeout itself. Note that there is no requirement
// that the ejbTimeout will be configured for CMT/RequiresNew.
// If there isn't a container-managed transaction,
// postEjbTimeout will still be called, and the database
// operations will be done in their own transaction. While
// partitioning the actions like this adds some complexity,
// it's preferable to pushing this detailed timer semantics
// into the container's callEJBTimeout logic.
//
// 2) Post-processing for setting up next timer delivery and
// other redelivery conditions.
//
boolean redeliver = container.callEJBTimeout(timerState, this);
if( shutdown_ ) {
// Server is shutting down so we can't finish processing
// the timer expiration.
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "Cancelling timeout for " + timerId
+
" due to server shutdown. Expiration will " +
" occur on server restart");
}
return;
}
// Resynchronize on timer state since a state change could have
// happened either within ejbTimeout or somewhere else
timerState = getTimerState(timerId);
if( timerState == null ) {
// This isn't an error case. The most likely reason is that
// the ejbTimeout method itself cancelled the timer.
logger.log(Level.FINE, "Timer no longer exists for " +
timerId + " after callEJBTimeout");
return;
}
synchronized(timerState) {
Date now = new Date();
if( timerState.isCancelled() ) {
// nothing more to do.
} else if( redeliver ) {
if( timerState.getNumFailedDeliveries() <
getMaxRedeliveries() ) {
Date redeliveryTimeout = new Date
(now.getTime() + getRedeliveryInterval());
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE,"Redelivering " + timerState);
}
rescheduleTask(timerId, redeliveryTimeout);
} else {
int numDeliv = timerState.getNumFailedDeliveries() + 1;
logger.log(Level.INFO,
"ejb.timer_exceeded_max_deliveries",
new Object[] { timerState.toString(),
new Integer(numDeliv)});
expungeTimer(timerId, true);
}
} else if( timerState.isPeriodic() ) {
// Any necessary transactional operations would have
// been handled in postEjbTimeout callback. Here, we
// just schedule the JDK timer task for the next ejbTimeout
Date expiration = calcNextFixedRateExpiration(timerState);
scheduleTask(timerId, expiration);
} else {
// Any necessary transactional operations would have
// been handled in postEjbTimeout callback. Nothing
// more to do for this single-action timer that was
// successfully delivered.
}
}
} catch(Exception e) {
logger.log(Level.FINE, "callEJBTimeout threw exception " +
"for timer id " + timerId , e);
expungeTimer(timerId, true);
} finally {
container.onLeavingContainer();
Switch.getSwitch().getCallFlowAgent().requestEnd();
}
}
/**
* Called from BaseContainer during callEJBTimeout after bean.ejbTimeout
* but before postInvoke. NOTE that this method is called whether or not
* the ejbTimeout method is configured for container-managed transactions.
* This method is *NOT* called if the container has already determined
* that a redelivery is necessary.
*
* @return true if successful , false otherwise.
*/
boolean postEjbTimeout(TimerPrimaryKey timerId) {
boolean success = true;
if( shutdown_ ) {
// Server is shutting down so we can't finish processing
// the timer expiration.
return success;
}
// Resynchronize on timer state since a state change could have
// happened either within ejbTimeout or somewhere else
RuntimeTimerState timerState = getTimerState(timerId);
if( timerState != null ) {
// Since the ejbTimeout was called successfully increment the
// delivery count
BaseContainer container = getContainer(timerState.getContainerId());
container.incrementDeliveredTimedObject();
synchronized(timerState) {
if( timerState.isCancelled() ) {
// nothing more to do.
} else {
try {
TimerLocal timerBean = getValidTimerFromDB( timerId );
if( null == timerBean ) {
return false;
}
if( timerState.isPeriodic() ) {
Date now = new Date();
timerBean.setLastExpiration(now);
// Since timer was successfully delivered, update
// last delivery time in database if that option is
// enabled.
// @@@ add configuration for update-db-on-delivery
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE,
"Setting last expiration " +
" for periodic timer " + timerState +
" to " + now);
}
} else {
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "Single-action timer " +
timerState + " was successfully delivered. "
+ " Removing...");
}
// Timer has expired sucessfully, so remove it.
cancelTimer(timerBean);
}
} catch(Exception e) {
// @@@ i18N
logger.log(Level.WARNING, "Error in post-ejbTimeout " +
"timer processing for " + timerState, e);
success = false;
}
}
}
}
return success;
}
/**
* This method is called to check if the timer is still valid.
* In the SE/EE case the timer might be cancelled by any other
* server instance (other than the owner server instance)
* that is part of the same cluster. Until we have a messaging
* system in place we would have to do a database query to
* check if the timer is still valid.
* Also check that the timer is owned by the current server instance
*
* @return false if the timer record is not found in the database,
* true if the timer is still valid.
*/
private boolean checkForTimerValidity(TimerPrimaryKey timerId) {
boolean result = true;
TimerLocal timerBean = getValidTimerFromDB( timerId );
if( null == timerBean) {
result = false;
}
return result;
}
private TimerLocal getValidTimerFromDB(TimerPrimaryKey timerId) {
boolean result = true;
TimerLocal timerBean = null;
try {
timerBean = findTimer(timerId);
// There is a possibility that the same timer might be
// migrated across to a different server. Hence check
// that the ownerId of the timer record is the same as
// the current server
if( ! ( timerBean.getOwnerId().equals(
ownerIdOfThisServer_) ) ) {
logger.log(Level.WARNING,
"The timer (" + timerId + ") is not owned by " +
"server (" + ownerIdOfThisServer_ + ") that " +
"initiated the ejbTimeout. This timer is now " +
"owned by (" + timerBean.getOwnerId() + "). \n" +
"Hence delete the timer from " +
ownerIdOfThisServer_ + "'s cache.");
result = false;
}
} catch( FinderException fex ) {
// The timer does not exist in the database
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "Timer :" + timerId +
": has been cancelled by another server instance. " +
"Expunging the timer from " + ownerIdOfThisServer_ +
"'s cache.");
}
result = false;
} finally {
if( !result ) {
// The timer is either not present in the database or it is now
// owned by some other server instance, hence remove the cache
//entry for the timer from the current server
expungeTimer(timerId, false);
timerBean = null;
} else {
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE,
"The Timer :" + timerId +
": is a valid timer for the server (" +
ownerIdOfThisServer_ + ")");
}
}
}
return timerBean;
}
/**
* This method is called back from the EJBTimerTask object
* on the JDK Timer Thread. Work performed in this callback
* should be short-lived, so do a little bookkeeping and then
* launch a separate thread to invoke ejbTimeout, etc.
*/
void taskExpired(TimerPrimaryKey timerId) {
RuntimeTimerState timerState = getTimerState(timerId);
if( timerState != null ) {
synchronized(timerState) {
if( timerState.isScheduled() ) {
timerState.delivered();
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE,
"Adding work pool task for timer " + timerId);
}
TaskExpiredWork work = new TaskExpiredWork(this, timerId);
com.sun.ejb.containers.util.ContainerWorkPool.addLast(work);
} else {
logger.log(Level.FINE, "Timer " + timerId +
" is not in scheduled state. Current state = "
+ timerState.stateToString());
}
}
} else {
logger.log(Level.FINE, "null timer state for timer id " + timerId);
}
return;
}
/**
* Generate a unique key for the persistent timer object.
* Key must be unique across server shutdown and startup, and
* within all server instances sharing the same timer table.
*/
private synchronized String getNextTimerId() {
if( nextTimerIdCounter_ <= 0 ) {
nextTimerIdMillis_ = System.currentTimeMillis();
nextTimerIdCounter_ = 1;
} else {
nextTimerIdCounter_++;
}
// @@@ Add cluster ID
return new String(nextTimerIdCounter_ +
TIMER_ID_SEP + nextTimerIdMillis_ +
TIMER_ID_SEP + serverName_ +
TIMER_ID_SEP + domainName_);
}
//
// Accessors for timer service properties.
//
private long getMinimumDeliveryInterval() {
return minimumDeliveryInterval_;
}
private long getMaxRedeliveries() {
return maxRedeliveries_;
}
private long getRedeliveryInterval() {
return redeliveryInterval_;
}
//
// This is a global cache of timer data *only for timers owned by
// this server instance*. It is not transactionally
// consistent. Operations requiring those semantics should query
// the database for TimerBean info. Any timer for which there is an
// active JDK timer task must be contained within this cache.
//
// Note : this class supports concurrent access.
//
private class TimerCache {
// Maps timer id to timer state.
private Map timers_;
// Map of timer information per container.
//
// For stateless session beans and message-driven beans,
// container id is mapped to a Long value representing the
// number of timers.
//
//
// For entity beans, container id is mapped to a list of
// primary keys. NOTE : This list can contain duplicate primary keys
// in the case where the same entity bean identity has more
// than one associated timer.
private Map containerTimers_;
public TimerCache() {
// Create unsynchronized collections. TimerCache will
// provide concurrency control.
timers_ = new HashMap();
containerTimers_ = new HashMap();
}
public synchronized void addTimer(TimerPrimaryKey timerId,
RuntimeTimerState timerState) {
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "Adding timer " + timerState);
}
timers_.put(timerId, timerState);
Long containerId = new Long(timerState.getContainerId());
Object containerInfo = containerTimers_.get(containerId);
if( timerState.timedObjectIsEntity() ) {
Collection entityBeans;
if( containerInfo == null ) {
// NOTE : This list *can* contain duplicates, since
// the same entity bean can be the timed object for
// multiple timers.
entityBeans = new ArrayList();
containerTimers_.put(containerId, entityBeans);
} else {
entityBeans = (Collection) containerInfo;
}
entityBeans.add(timerState.getTimedObjectPrimaryKey());
} else {
Long timerCount = (containerInfo == null) ? new Long(1) :
new Long(((Long) containerInfo).longValue() + 1);
containerTimers_.put(containerId, timerCount);
}
}
/**
* Remove a timer from the cache. This should be coded
* defensively since it's possible it will be called multiple
* times for the same timer.
*/
public synchronized void removeTimer(TimerPrimaryKey timerId) {
if( logger.isLoggable(Level.FINE) ) {
logger.log(Level.FINE, "Removing timer " + timerId);
}
RuntimeTimerState timerState = (RuntimeTimerState)
timers_.remove(timerId);
if( timerState == null) {
return;
}
Long containerId = new Long(timerState.getContainerId());
Object containerInfo = containerTimers_.get(containerId);
if( containerInfo != null ) {
if( timerState.timedObjectIsEntity() ) {
Collection entityBeans = (Collection) containerInfo;
if( entityBeans.size() == 1 ) {
// Only one left -- blow away the container.
containerTimers_.remove(containerId);
} else {
// Remove a single instance of this primary key
// from the list. There could still be other
// instances of the same primary key.
entityBeans.remove
(timerState.getTimedObjectPrimaryKey());
}
} else {
long timerCount = ((Long) containerInfo).longValue();
if( timerCount == 1 ) {
// Only one left -- blow away the container
containerTimers_.remove(containerId);
} else {
Long newCount = new Long(timerCount - 1);
containerTimers_.put(containerId, newCount);
}
}
}
}
public synchronized RuntimeTimerState getTimerState(TimerPrimaryKey
timerId) {
return (RuntimeTimerState) timers_.get(timerId);
}
// True if the given entity bean has any timers and false otherwise.
public synchronized boolean entityBeanHasTimers(long containerId,
Object pkey) {
Object containerInfo = containerTimers_.get(new Long(containerId));
return (containerInfo != null) ?
((Collection) containerInfo).contains(pkey) : false;
}
// True if the ejb represented by this container id has any timers
// and false otherwise.
public synchronized boolean containerHasTimers(long containerId) {
return containerTimers_.containsKey(new Long(containerId));
}
// Placeholder for logic to ensure timer cache consistency.
public synchronized void validate() {
}
} //TimerCache{}
private File getTimerServiceShutdownFile()
throws Exception
{
File timerServiceShutdownDirectory;
File timerServiceShutdownFile;
InstanceEnvironment env = ApplicationServer.getServerContext().
getInstanceEnvironment();
AppsManager appsManager = new AppsManager(env, false);
String j2eeAppPath = appsManager.getLocation(appID);
timerServiceShutdownDirectory = new File(j2eeAppPath + File.separator);
timerServiceShutdownDirectory.mkdirs();
timerServiceShutdownFile = new File(j2eeAppPath + File.separator
+ TIMER_SERVICE_FILE);
return timerServiceShutdownFile;
}
private long getTimerServiceDownAt() {
long timerServiceWentDownAt = -1;
try {
File timerServiceShutdownFile = getTimerServiceShutdownFile();
if (timerServiceShutdownFile.exists()) {
DateFormat dateFormat =
new SimpleDateFormat(TIMER_SERVICE_DOWNTIME_FORMAT);
FileReader fr = new FileReader(timerServiceShutdownFile);
BufferedReader br = new BufferedReader(fr, 128);
String line = br.readLine();
Date myDate = dateFormat.parse(line);
timerServiceWentDownAt = myDate.getTime();
logger.log(Level.INFO, "ejb.timer_service_last_shutdown",
new Object[] { line });
} else {
logger.log(Level.WARNING, "ejb.timer_service_shutdown_unknown",
new Object[] { timerServiceShutdownFile });
}
} catch (Throwable th) {
logger.log(Level.WARNING, "ejb.timer_service_shutdown_unknown",
new Object[] { "" });
logger.log(Level.WARNING, "", th);
}
return timerServiceWentDownAt;
}
/**
* Called from TimerBeanContainer
*/
public void onShutdown() {
try {
DateFormat dateFormat =
new SimpleDateFormat(TIMER_SERVICE_DOWNTIME_FORMAT);
String downTimeStr = dateFormat.format(new Date());
File timerServiceShutdownFile = getTimerServiceShutdownFile();
FileWriter fw = new FileWriter(timerServiceShutdownFile);
PrintWriter pw = new PrintWriter(fw);
pw.println(downTimeStr);
pw.flush();
pw.close();
fw.close();
logger.log(Level.INFO, "ejb.timer_service_shutdown_msg",
new Object[] { downTimeStr });
} catch (Throwable th) {
logger.log(Level.WARNING, "ejb.timer_service_shutdown_unknown",
new Object[] { TIMER_SERVICE_FILE });
logger.log(Level.WARNING, "", th);
}
}
/**
* This class gets a callback on a worker thread where the actual
* ejbTimeout invocation will be made.
*/
private static class TaskExpiredWork
implements com.sun.enterprise.util.threadpool.Servicable
{
private EJBTimerService timerService_;
private TimerPrimaryKey timerId_;
public TaskExpiredWork(EJBTimerService timerService,
TimerPrimaryKey timerId) {
timerService_ = timerService;
timerId_ = timerId;
}
public void prolog() { }
public void epilog() { }
public void service() { run(); }
public void run() {
// Delegate to Timer Service.
timerService_.deliverTimeout(timerId_);
}
} // TaskExpiredWork
}
|
