/**
* Copyright 2010 JBoss Inc
*
* 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.
*/
package org.drools.time.impl;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;
import org.drools.runtime.Calendars;
import org.drools.time.Trigger;
public class CronTrigger
implements
Trigger {
protected static final int YEAR_TO_GIVEUP_SCHEDULING_AT = 2299;
private CronExpression cronEx = null;
private Date startTime = null;
private Date endTime = null;
private int repeatLimit;
private int repeatCount;
private Date nextFireTime = null;
private Date previousFireTime = null;
private transient TimeZone timeZone = null;
private String[] calendarNames;
private Calendars calendars;
public CronTrigger(long timestamp,
Date startTime,
Date endTime,
int repeatLimit,
String cronExpression,
String[] calendarNames,
Calendars calendars) {
this( timestamp,
startTime,
endTime,
repeatLimit,
determineCronExpression( cronExpression ),
calendarNames,
calendars );
}
public CronTrigger(long timestamp,
Date startTime,
Date endTime,
int repeatLimit,
CronExpression cronExpression,
String[] calendarNames,
Calendars calendars) {
setCronExpression( cronExpression );
this.repeatLimit = repeatLimit;
if ( startTime == null ) {
startTime = new Date( timestamp );
}
setStartTime( startTime );
if ( endTime != null ) {
setEndTime( endTime );
}
setTimeZone( TimeZone.getDefault() );
// Set the first FireTime, this is sensitive to StartTime
this.nextFireTime = new Date( timestamp - 1000l );
setFirstFireTimeAfter();
this.calendarNames = calendarNames;
this.calendars = calendars;
// Update to next include time, if we have calendars
updateToNextIncludeDate();
}
public Date getStartTime() {
return this.startTime;
}
public void setStartTime(Date startTime) {
if ( startTime == null ) {
throw new IllegalArgumentException( "Start time cannot be null" );
}
Date eTime = getEndTime();
if ( eTime != null && startTime != null && eTime.before( startTime ) ) {
throw new IllegalArgumentException( "End time cannot be before start time" );
}
// round off millisecond...
// Note timeZone is not needed here as parameter for
// Calendar.getInstance(),
// since time zone is implicit when using a Date in the setTime method.
Calendar cl = Calendar.getInstance();
cl.setTime( startTime );
cl.set( Calendar.MILLISECOND,
0 );
this.startTime = cl.getTime();
}
/**
* <p>
* Get the time at which the <code>CronTrigger</code> should quit
* repeating - even if repeastCount isn't yet satisfied.
* </p>
*
* @see #getFinalFireTime()
*/
public Date getEndTime() {
return this.endTime;
}
public void setEndTime(Date endTime) {
Date sTime = getStartTime();
if ( sTime != null && endTime != null && sTime.after( endTime ) ) {
throw new IllegalArgumentException( "End time cannot be before start time" );
}
this.endTime = endTime;
}
/**
* <p>
* Returns the next time at which the <code>Trigger</code> is scheduled to fire. If
* the trigger will not fire again, <code>null</code> will be returned. Note that
* the time returned can possibly be in the past, if the time that was computed
* for the trigger to next fire has already arrived, but the scheduler has not yet
* been able to fire the trigger (which would likely be due to lack of resources
* e.g. threads).
* </p>
*
* <p>The value returned is not guaranteed to be valid until after the <code>Trigger</code>
* has been added to the scheduler.
* </p>
*
* @see TriggerUtils#computeFireTimesBetween(Trigger, org.quartz.Calendar , Date, Date)
*/
public Date getNextFireTime() {
return this.nextFireTime;
}
/**
* <p>
* Returns the previous time at which the <code>CronTrigger</code>
* fired. If the trigger has not yet fired, <code>null</code> will be
* returned.
*/
public Date getPreviousFireTime() {
return this.previousFireTime;
}
/**
* <p>
* Sets the next time at which the <code>CronTrigger</code> will fire.
* <b>This method should not be invoked by client code.</b>
* </p>
*/
public void setNextFireTime(Date nextFireTime) {
this.nextFireTime = nextFireTime;
}
/**
* <p>
* Set the previous time at which the <code>CronTrigger</code> fired.
* </p>
*
* <p>
* <b>This method should not be invoked by client code.</b>
* </p>
*/
public void setPreviousFireTime(Date previousFireTime) {
this.previousFireTime = previousFireTime;
}
/**
* <p>
* Returns the time zone for which the <code>cronExpression</code> of
* this <code>CronTrigger</code> will be resolved.
* </p>
*/
public TimeZone getTimeZone() {
if ( this.cronEx != null ) {
return this.cronEx.getTimeZone();
}
if ( this.timeZone == null ) {
this.timeZone = TimeZone.getDefault();
}
return this.timeZone;
}
/**
* <p>
* Sets the time zone for which the <code>cronExpression</code> of this
* <code>CronTrigger</code> will be resolved.
* </p>
*
* <p>If {@link #setCronExpression(CronExpression)} is called after this
* method, the TimeZon setting on the CronExpression will "win". However
* if {@link #setCronExpression(String)} is called after this method, the
* time zone applied by this method will remain in effect, since the
* String cron expression does not carry a time zone!
*/
public void setTimeZone(TimeZone timeZone) {
if ( this.cronEx != null ) {
this.cronEx.setTimeZone( timeZone );
}
this.timeZone = timeZone;
}
public void setCronExpression(String cronExpression) {
setCronExpression( determineCronExpression( cronExpression ) );
}
public void setCronExpression(CronExpression cronExpression) {
TimeZone origTz = getTimeZone();
this.cronEx = cronExpression;
this.cronEx.setTimeZone( origTz );
}
public static CronExpression determineCronExpression(String cronExpression) {
try {
return new CronExpression( cronExpression );
} catch ( Exception e ) {
throw new RuntimeException( "Unable to parse cron expression '" + cronExpression + "'",
e );
}
}
public Date hasNextFireTime() {
return this.nextFireTime;
}
public Date nextFireTime() {
Date date = this.nextFireTime;
this.nextFireTime = getTimeAfter( this.nextFireTime );
updateToNextIncludeDate();
if ( this.endTime != null && this.nextFireTime.after( this.endTime ) ) {
this.nextFireTime = null;
} else if ( repeatLimit != -1 && repeatCount >= repeatLimit ) {
this.nextFireTime = null;
}
return date;
}
/**
* <p>
* Returns the next time at which the <code>CronTrigger</code> will fire,
* after the given time. If the trigger will not fire after the given time,
* <code>null</code> will be returned.
* </p>
*
* <p>
* Note that the date returned is NOT validated against the related
* org.quartz.Calendar (if any)
* </p>
*/
public void setFirstFireTimeAfter() {
if ( getStartTime().after( this.nextFireTime ) ) {
this.nextFireTime = new Date( getStartTime().getTime() - 1000l );
}
if ( getEndTime() != null && (this.nextFireTime.compareTo( getEndTime() ) >= 0) ) {
this.nextFireTime = null;
}
Date pot = getTimeAfter( this.nextFireTime );
if ( getEndTime() != null && pot != null && pot.after( getEndTime() ) ) {
this.nextFireTime = null;
} else {
this.nextFireTime = pot;
}
}
protected Date getTimeAfter(Date afterTime) {
this.repeatCount++;
return (this.cronEx == null) ? null : this.cronEx.getTimeAfter( afterTime );
}
public void updateToNextIncludeDate() {
if ( this.calendars == null || calendarNames == null || calendarNames.length == 0 ) {
// There are no assigned calendars
return;
}
// If we have calendars, check we can fire, or get next time until we can fire.
while ( this.nextFireTime != null && (this.endTime == null || this.nextFireTime.before( this.endTime )) ) {
// this will loop forever if the trigger repeats forever and
// included calendar position cannot be found
boolean included = true;
for ( String calName : this.calendarNames ) {
// all calendars must not block, as soon as one blocks break, so we can check next time slot
org.drools.time.Calendar cal = this.calendars.get( calName );
if ( cal != null && !cal.isTimeIncluded( this.nextFireTime.getTime() ) ) {
included = false;
break;
}
}
if ( included == true ) {
// if no calendars blocked, break
break;
} else {
// otherwise increase the time and try again
this.nextFireTime = getTimeAfter( this.nextFireTime );
}
}
}
}