/*
* Bitronix Transaction Manager
*
* Copyright (c) 2010, Bitronix Software.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program 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 distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package bitronix.tm.timer;
import bitronix.tm.BitronixTransaction;
import bitronix.tm.TransactionManagerServices;
import bitronix.tm.recovery.Recoverer;
import bitronix.tm.resource.common.XAPool;
import bitronix.tm.utils.Service;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.*;
/**
* Timed tasks service.
*
* @author lorban
*/
public class TaskScheduler extends Thread implements Service {
private final static Logger log = LoggerFactory.getLogger(TaskScheduler.class);
private final List tasks = Collections.synchronizedList(new ArrayList());
private volatile boolean active = true;
public TaskScheduler() {
// it is up to the ShutdownHandler to control the lifespan of the JVM and give some time for this thread
// to die gracefully, meaning enough time for all tasks to get executed. This is why it is set as daemon.
setDaemon(true);
setName("bitronix-scheduler");
}
/**
* Get the amount of tasks currently queued.
* @return the amount of tasks currently queued.
*/
public int countTasksQueued() {
return tasks.size();
}
public synchronized void shutdown() {
try {
long gracefulShutdownTime = TransactionManagerServices.getConfiguration().getGracefulShutdownInterval() * 1000;
if (log.isDebugEnabled()) log.debug("graceful scheduler shutdown interval: " + gracefulShutdownTime + "ms");
setActive(false);
join(gracefulShutdownTime);
} catch (InterruptedException ex) {
log.error("could not stop the task scheduler within " + TransactionManagerServices.getConfiguration().getGracefulShutdownInterval() + "s");
}
}
/**
* Schedule a task that will mark the transaction as timed out at the specified date. If this method is called
* with the same transaction multiple times, the previous timeout date is dropped and replaced by the new one.
* @param transaction the transaction to mark as timeout.
* @param executionTime the date at which the transaction must be marked.
*/
public void scheduleTransactionTimeout(BitronixTransaction transaction, Date executionTime) {
if (log.isDebugEnabled()) log.debug("scheduling transaction timeout task on " + transaction + " for " + executionTime);
if (transaction == null)
throw new IllegalArgumentException("expected a non-null transaction");
if (executionTime == null)
throw new IllegalArgumentException("expected a non-null execution date");
TransactionTimeoutTask task = new TransactionTimeoutTask(transaction, executionTime, this);
addTask(task);
if (log.isDebugEnabled()) log.debug("scheduled " + task + ", total task(s) queued: " + tasks.size());
}
/**
* Cancel the task that will mark the transaction as timed out at the specified date.
* @param transaction the transaction to mark as timeout.
*/
public void cancelTransactionTimeout(BitronixTransaction transaction) {
if (log.isDebugEnabled()) log.debug("cancelling transaction timeout task on " + transaction);
if (transaction == null)
throw new IllegalArgumentException("expected a non-null transaction");
if (!removeTaskByObject(transaction))
if (log.isDebugEnabled()) log.debug("no task found based on object " + transaction);
}
/**
* Schedule a task that will run background recovery at the specified date.
* @param recoverer the recovery implementation to use.
* @param executionTime the date at which the transaction must be marked.
*/
public void scheduleRecovery(Recoverer recoverer, Date executionTime) {
if (log.isDebugEnabled()) log.debug("scheduling recovery task for " + executionTime);
if (recoverer == null)
throw new IllegalArgumentException("expected a non-null recoverer");
if (executionTime == null)
throw new IllegalArgumentException("expected a non-null execution date");
RecoveryTask task = new RecoveryTask(recoverer, executionTime, this);
addTask(task);
if (log.isDebugEnabled()) log.debug("scheduled " + task + ", total task(s) queued: " + tasks.size());
}
/**
* Cancel the task that will run background recovery at the specified date.
* @param recoverer the recovery implementation to use.
*/
public void cancelRecovery(Recoverer recoverer) {
if (log.isDebugEnabled()) log.debug("cancelling recovery task");
if (!removeTaskByObject(recoverer))
if (log.isDebugEnabled()) log.debug("no task found based on object " + recoverer);
}
/**
* Schedule a task that will tell a XA pool to close idle connections. The execution time will be provided by the
* XA pool itself via the {@link bitronix.tm.resource.common.XAPool#getNextShrinkDate()}.
* @param xaPool the XA pool to notify.
*/
public void schedulePoolShrinking(XAPool xaPool) {
Date executionTime = xaPool.getNextShrinkDate();
if (log.isDebugEnabled()) log.debug("scheduling pool shrinking task on " + xaPool + " for " + executionTime);
if (executionTime == null)
throw new IllegalArgumentException("expected a non-null execution date");
PoolShrinkingTask task = new PoolShrinkingTask(xaPool, executionTime, this);
addTask(task);
if (log.isDebugEnabled()) log.debug("scheduled " + task + ", total task(s) queued: " + tasks.size());
}
/**
* Cancel the task that will tell a XA pool to close idle connections.
* @param xaPool the XA pool to notify.
*/
public void cancelPoolShrinking(XAPool xaPool) {
if (log.isDebugEnabled()) log.debug("cancelling pool shrinking task on " + xaPool);
if (xaPool == null)
throw new IllegalArgumentException("expected a non-null XA pool");
if (!removeTaskByObject(xaPool))
if (log.isDebugEnabled()) log.debug("no task found based on object " + xaPool);
}
private void addTask(Task task) {
synchronized (tasks) {
removeTaskByObject(task.getObject());
tasks.add(task);
}
}
private boolean removeTaskByObject(Object obj) {
synchronized (tasks) {
if (log.isDebugEnabled()) log.debug("removing task by " + obj);
for (int i = 0; i < tasks.size(); i++) {
Task task = (Task) tasks.get(i);
if (task.getObject() == obj) {
tasks.remove(task);
if (log.isDebugEnabled()) log.debug("cancelled " + task + ", total task(s) still queued: " + tasks.size());
return true;
}
}
return false;
}
}
void setActive(boolean active) {
this.active = active;
}
private boolean isActive() {
return active;
}
public void run() {
while (isActive()) {
try {
executeElapsedTasks();
Thread.sleep(500); // execute twice per second. That's enough precision.
} catch (InterruptedException ex) {
// ignore
}
} // while
}
private void executeElapsedTasks() {
if (this.tasks.size() == 0)
return;
// Copying a collection means iterating it so this block must be synchronized
List tasks;
synchronized (this.tasks) {
tasks = new ArrayList(this.tasks);
}
Iterator it = tasks.iterator();
while (it.hasNext()) {
Task task = (Task) it.next();
if (task.getExecutionTime().compareTo(new Date()) <= 0) { // if the execution time is now or in the past
if (log.isDebugEnabled()) log.debug("running " + task);
try {
task.execute();
if (log.isDebugEnabled()) log.debug("successfully ran " + task);
} catch (Exception ex) {
log.warn("error running " + task, ex);
} finally {
this.tasks.remove(task);
if (log.isDebugEnabled()) log.debug("total task(s) still queued: " + tasks.size());
}
} // if
} // while
}
}