/*
* Copyright 2004-2005 OpenSymphony
*
* Licensed 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.
*
*/
/*
* Previously Copyright (c) 2001-2004 James House
*/
package org.quartz.core;
import java.util.Random;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.quartz.Job;
import org.quartz.JobPersistenceException;
import org.quartz.SchedulerException;
import org.quartz.Trigger;
import org.quartz.spi.TriggerFiredBundle;
/**
* <p>
* The thread responsible for performing the work of firing <code>{@link Trigger}</code>
* s that are registered with the <code>{@link QuartzScheduler}</code>.
* </p>
*
* @see QuartzScheduler
* @see Job
* @see Trigger
*
* @author James House
*/
public class QuartzSchedulerThread extends Thread {
/*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* Data members.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
private QuartzScheduler qs;
private QuartzSchedulerResources qsRsrcs;
private Object pauseLock = new Object();
private Object idleLock = new Object();
private boolean signaled;
private boolean paused;
private boolean halted;
private SchedulingContext ctxt = null;
private Random random = new Random(System.currentTimeMillis());
// When the scheduler finds there is no current trigger to fire, how long
// it should wait until checking again...
private static long DEFAULT_IDLE_WAIT_TIME = 30L * 1000L;
private long idleWaitTime = DEFAULT_IDLE_WAIT_TIME;
private int idleWaitVariablness = 7 * 1000;
private long dbFailureRetryInterval = 15L * 1000L;
/*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* Constructors.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
/**
* <p>
* Construct a new <code>QuartzSchedulerThread</code> for the given
* <code>QuartzScheduler</code> as a non-daemon <code>Thread</code>
* with normal priority.
* </p>
*/
QuartzSchedulerThread(QuartzScheduler qs, QuartzSchedulerResources qsRsrcs,
SchedulingContext ctxt) {
this(qs, qsRsrcs, ctxt, false, Thread.NORM_PRIORITY);
}
/**
* <p>
* Construct a new <code>QuartzSchedulerThread</code> for the given
* <code>QuartzScheduler</code> as a <code>Thread</code> with the given
* attributes.
* </p>
*/
QuartzSchedulerThread(QuartzScheduler qs, QuartzSchedulerResources qsRsrcs,
SchedulingContext ctxt, boolean setDaemon, int threadPrio) {
super(qs.getSchedulerThreadGroup(), qsRsrcs.getThreadName());
this.qs = qs;
this.qsRsrcs = qsRsrcs;
this.ctxt = ctxt;
this.setDaemon(setDaemon);
this.setPriority(threadPrio);
// start the underlying thread, but put this object into the 'paused'
// state
// so processing doesn't start yet...
paused = true;
halted = false;
this.start();
}
/*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* Interface.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
void setIdleWaitTime(long waitTime) {
idleWaitTime = waitTime;
idleWaitVariablness = (int) (waitTime * 0.2);
}
private long getDbFailureRetryInterval() {
return dbFailureRetryInterval;
}
public void setDbFailureRetryInterval(long dbFailureRetryInterval) {
this.dbFailureRetryInterval = dbFailureRetryInterval;
}
private long getRandomizedIdleWaitTime() {
return idleWaitTime - random.nextInt(idleWaitVariablness);
}
/**
* <p>
* Signals the main processing loop to pause at the next possible point.
* </p>
*/
void togglePause(boolean pause) {
synchronized (pauseLock) {
paused = pause;
if (paused) {
signalSchedulingChange();
} else {
pauseLock.notify();
}
}
}
/**
* <p>
* Signals the main processing loop to pause at the next possible point.
* </p>
*/
void halt() {
synchronized (pauseLock) {
halted = true;
if (paused) {
pauseLock.notify();
} else {
signalSchedulingChange();
}
}
}
boolean isPaused() {
return paused;
}
/**
* <p>
* Signals the main processing loop that a change in scheduling has been
* made - in order to interrupt any sleeping that may be occuring while
* waiting for the fire time to arrive.
* </p>
*/
void signalSchedulingChange() {
signaled = true;
}
/**
* <p>
* The main processing loop of the <code>QuartzSchedulerThread</code>.
* </p>
*/
public void run() {
boolean lastAcquireFailed = false;
while (!halted) {
signaled = false;
try {
// check if we're supposed to pause...
synchronized (pauseLock) {
while (paused && !halted) {
try {
// wait until togglePause(false) is called...
pauseLock.wait(100L);
} catch (InterruptedException ignore) {
}
}
if (halted) {
break;
}
}
Trigger trigger = null;
long now = System.currentTimeMillis();
try {
trigger = qsRsrcs.getJobStore().acquireNextTrigger(
ctxt, now + idleWaitTime);
lastAcquireFailed = false;
} catch (JobPersistenceException jpe) {
if(!lastAcquireFailed)
qs.notifySchedulerListenersError(
"An error occured while scanning for the next trigger to fire.",
jpe);
lastAcquireFailed = true;
}
catch (RuntimeException e) {
if(!lastAcquireFailed)
getLog().error("quartzSchedulerThreadLoop: RuntimeException "
+e.getMessage(), e);
lastAcquireFailed = true;
}
if (trigger != null) {
now = System.currentTimeMillis();
long triggerTime = trigger.getNextFireTime().getTime();
long timeUntilTrigger = triggerTime - now;
long spinInterval = 10;
// this looping may seem a bit silly, but it's the
// current work-around
// for a dead-lock that can occur if the Thread.sleep()
// is replaced with
// a obj.wait() that gets notified when the signal is
// set...
// so to be able to detect the signal change without
// sleeping the entire
// timeUntilTrigger, we spin here... don't worry
// though, this spinning
// doesn't even register 0.2% cpu usage on a pentium 4.
int numPauses = (int) (timeUntilTrigger / spinInterval);
while (numPauses >= 0 && !signaled) {
try {
Thread.sleep(spinInterval);
} catch (InterruptedException ignore) {
}
now = System.currentTimeMillis();
timeUntilTrigger = triggerTime - now;
numPauses = (int) (timeUntilTrigger / spinInterval);
}
if (signaled) {
try {
qsRsrcs.getJobStore().releaseAcquiredTrigger(
ctxt, trigger);
} catch (JobPersistenceException jpe) {
qs.notifySchedulerListenersError(
"An error occured while releasing trigger '"
+ trigger.getFullName() + "'",
jpe);
// db connection must have failed... keep
// retrying until it's up...
releaseTriggerRetryLoop(trigger);
} catch (RuntimeException e) {
getLog().error(
"releaseTriggerRetryLoop: RuntimeException "
+e.getMessage(), e);
// db connection must have failed... keep
// retrying until it's up...
releaseTriggerRetryLoop(trigger);
}
signaled = false;
continue;
}
// set trigger to 'executing'
TriggerFiredBundle bndle = null;
try {
bndle = qsRsrcs.getJobStore().triggerFired(ctxt,
trigger);
} catch (SchedulerException se) {
qs.notifySchedulerListenersError(
"An error occured while firing trigger '"
+ trigger.getFullName() + "'", se);
} catch (RuntimeException e) {
getLog().error(
"RuntimeException while firing trigger " +
trigger.getFullName(), e);
// db connection must have failed... keep
// retrying until it's up...
releaseTriggerRetryLoop(trigger);
}
// it's possible to get 'null' if the trigger was paused,
// blocked, or other similar occurances that prevent it being
// fired at this time...
if (bndle == null) {
try {
qsRsrcs.getJobStore().releaseAcquiredTrigger(ctxt,
trigger);
} catch (SchedulerException se) {
qs.notifySchedulerListenersError(
"An error occured while releasing trigger '"
+ trigger.getFullName() + "'", se);
// db connection must have failed... keep retrying
// until it's up...
releaseTriggerRetryLoop(trigger);
}
continue;
}
// TODO: improvements:
//
// 1- get thread from pool before firing trigger.
// 2- make sure we can get a job runshell first as well, or
// don't let that throw an exception (right now it never does,
// bugthe signature says it can).
// 3- acquire more triggers at a time (based on num threads?)
JobRunShell shell = null;
try {
shell = qsRsrcs.getJobRunShellFactory().borrowJobRunShell();
shell.initialize(qs, bndle);
} catch (SchedulerException se) {
try {
qsRsrcs.getJobStore().triggeredJobComplete(ctxt,
trigger, bndle.getJobDetail(), Trigger.INSTRUCTION_SET_ALL_JOB_TRIGGERS_ERROR);
} catch (SchedulerException se2) {
qs.notifySchedulerListenersError(
"An error occured while releasing trigger '"
+ trigger.getFullName() + "'", se2);
// db connection must have failed... keep retrying
// until it's up...
errorTriggerRetryLoop(bndle);
}
continue;
}
qsRsrcs.getThreadPool().runInThread(shell);
continue;
}
// this looping may seem a bit silly, but it's the current
// work-around
// for a dead-lock that can occur if the Thread.sleep() is replaced
// with
// a obj.wait() that gets notified when the signal is set...
// so to be able to detect the signal change without sleeping the
// entier
// getRandomizedIdleWaitTime(), we spin here... don't worry though,
// the
// CPU usage of this spinning can't even be measured on a pentium
// 4.
now = System.currentTimeMillis();
long waitTime = now + getRandomizedIdleWaitTime();
long timeUntilContinue = waitTime - now;
long spinInterval = 10;
int numPauses = (int) (timeUntilContinue / spinInterval);
while (numPauses > 0 && !signaled) {
try {
Thread.sleep(10L);
} catch (InterruptedException ignore) {
}
now = System.currentTimeMillis();
timeUntilContinue = waitTime - now;
numPauses = (int) (timeUntilContinue / spinInterval);
}
}
catch(RuntimeException re) {
getLog().error("Runtime error occured in main trigger firing loop.", re);
}
} // loop...
// drop references to scheduler stuff to aid garbage collection...
qs = null;
qsRsrcs = null;
}
public void errorTriggerRetryLoop(TriggerFiredBundle bndle) {
int retryCount = 0;
try {
while (!halted) {
try {
Thread.sleep(getDbFailureRetryInterval()); // retry every N
// seconds (the db
// connection must
// be failed)
retryCount++;
qsRsrcs.getJobStore().triggeredJobComplete(ctxt,
bndle.getTrigger(), bndle.getJobDetail(), Trigger.INSTRUCTION_SET_ALL_JOB_TRIGGERS_ERROR);
retryCount = 0;
break;
} catch (JobPersistenceException jpe) {
if(retryCount % 4 == 0)
qs.notifySchedulerListenersError(
"An error occured while releasing trigger '"
+ bndle.getTrigger().getFullName() + "'", jpe);
} catch (RuntimeException e) {
getLog().error("releaseTriggerRetryLoop: RuntimeException "+e.getMessage(), e);
} catch (InterruptedException e) {
getLog().error("releaseTriggerRetryLoop: InterruptedException "+e.getMessage(), e);
}
}
} finally {
if(retryCount == 0)
getLog().info("releaseTriggerRetryLoop: connection restored.");
}
}
public void releaseTriggerRetryLoop(Trigger trigger) {
int retryCount = 0;
try {
while (!halted) {
try {
Thread.sleep(getDbFailureRetryInterval()); // retry every N
// seconds (the db
// connection must
// be failed)
retryCount++;
qsRsrcs.getJobStore().releaseAcquiredTrigger(ctxt, trigger);
retryCount = 0;
break;
} catch (JobPersistenceException jpe) {
if(retryCount % 4 == 0)
qs.notifySchedulerListenersError(
"An error occured while releasing trigger '"
+ trigger.getFullName() + "'", jpe);
} catch (RuntimeException e) {
getLog().error("releaseTriggerRetryLoop: RuntimeException "+e.getMessage(), e);
} catch (InterruptedException e) {
getLog().error("releaseTriggerRetryLoop: InterruptedException "+e.getMessage(), e);
}
}
} finally {
if(retryCount == 0)
getLog().info("releaseTriggerRetryLoop: connection restored.");
}
}
public static Log getLog() {
return LogFactory.getLog(QuartzSchedulerThread.class);
}
} // end of QuartzSchedulerThread