org.oddjob.scheduling

Class Timer

java.lang.Object

org.oddjob.framework.extend.BaseComponent

org.oddjob.framework.extend.BasePrimary

org.oddjob.scheduling.ScheduleBase

org.oddjob.scheduling.TimerBase

org.oddjob.scheduling.Timer

All Implemented Interfaces:

java.io.Serializable, java.lang.Runnable, ArooaContextAware, ArooaSessionAware, Forceable, PropertyChangeNotifier, Iconic, LogEnabled, Resettable, Stateful, Stoppable, Structural

public class Timer
extends TimerBase

Description

Provides a simple timer for periodic or once only execution of the child job.

Schedules

Once only execution:

• TimeSchedule
• DateSchedule
• CountSchedule (With a count of 1)

Recurring executions:

• YearlySchedule
• MonthlySchedule
• WeeklySchedule
• DailySchedule
• IntervalSchedule

Holidays:

• BrokenSchedule
• DayAfterSchedule
• DayBeforeSchedule

Missed Executions

If Oddjob is running with a persister missed executions fire immediately one after the other until all missed executions have run.

This can be overridden with the skipMissedRuns property.

If a timer is started after the initial execution time but within the interval of the schedule - execution will happen immediately. Extended intervals are created using the from properties instead of the at/in/on properties of schedules.

Changing The Next Due Time

There are two ways to change the next due date of a timer. They both require that the timer has been started but is not yet executing, and they both involve dynamically setting properties of the job which can be done via the 'Job' -> 'Set Property' menu item in Oddjob Explorer or via the SetJob job within Oddjob.

The first method is to set the next due date directly with the nextDue property. The existing timer is cancelled and the job rescheduled to run at this time. If the time is in the past, the job will run immediately.

The second method is to set the the reschedule property with a date and time. The next due date is calculated by applying the date and time the schedule. This is particularly useful for advancing a timer.

Retrying Failed Jobs

Nest a Retry job.

Recording the Outcome of Runs

Nest an ArchiveJob.

Distributed Scheduling

Nest a GrabJob.

For More Information

For more information see the Scheduling section of the User Guide.

Example

A Timer that runs at 10am each day, Monday to Friday.

<oddjob>
    <job>
        <scheduling:timer id="timer" xmlns:scheduling="http://rgordon.co.uk/oddjob/scheduling" xmlns:schedules="http://rgordon.co.uk/oddjob/schedules">
            <schedule>
                <schedules:weekly from="Monday" to="Friday">
                    <refinement>
                        <schedules:daily at="10:00"/>
                    </refinement>
                </schedules:weekly>
            </schedule>
            <job>
                <echo id="work">Doing some work at ${timer.current.fromDate}</echo>
            </job>
        </scheduling:timer>
    </job>
</oddjob>

Example

Run once at 10am or any time after.

<oddjob>
    <job>
        <sequential>
            <jobs>
                <echo id="big-report" name="Pretend this is a Long Running Report">Meaning of Life: 42</echo>
                <scheduling:timer id="timer" xmlns:scheduling="http://rgordon.co.uk/oddjob/scheduling">
                    <schedule>
                        <schedules:time from="10:00" xmlns:schedules="http://rgordon.co.uk/oddjob/schedules"/>
                    </schedule>
                    <job>
                        <echo name="Pretend this Forwards the Long Running Report">Emailing: ${big-report.text}</echo>
                    </job>
                </scheduling:timer>
            </jobs>
        </sequential>
    </job>
</oddjob>

If the report completes before 10am the timer will schedule it to be e-mailed at 10am. If the report completes after 10am it is e-mailed immediately.

Example

Use a timer to stop a long running job.

<oddjob>
    <job>
        <sequential id="main" name="Stop Overdue Job">
            <jobs>
                <scheduling:timer id="timer" xmlns:scheduling="http://rgordon.co.uk/oddjob/scheduling">
                    <schedule>
                        <schedules:count count="1" xmlns:schedules="http://rgordon.co.uk/oddjob/schedules">
                            <refinement>
                                <schedules:after>
                                    <schedule>
                                        <schedules:interval interval="00:00:10"/>
                                    </schedule>
                                </schedules:after>
                            </refinement>
                        </schedules:count>
                    </schedule>
                    <job>
                         <stop job="${long-job}" name="Stop Long Running Job"/>
                    </job>
                </scheduling:timer>
                <wait id="long-job" name="A Long Running Job"/>
            </jobs>
        </sequential>
    </job>
</oddjob>

The job will be stopped after 10 seconds. If the job has already completed the stop will have no affect.

Example

Manually setting the next due date of the timer. When the set job is run manually the job will be schedule to run at the new time.

<oddjob>
    <job>
        <sequential>
            <jobs>
                <scheduling:timer id="timer" xmlns:scheduling="http://rgordon.co.uk/oddjob/scheduling">
                    <schedule>
                        <schedules:date on="9999-12-31" xmlns:schedules="http://rgordon.co.uk/oddjob/schedules"/>
                    </schedule>
                    <clock>
                        <value value="${clock}"/>
                    </clock>
                    <job>
                        <echo id="echo">Running at ${timer.current.fromDate}</echo>
                    </job>
                </scheduling:timer>
                <folder>
                    <jobs>
                        <set id="set">
                            <values>
                                <date date="2012-12-27 08:02" key="timer.nextDue"/>
                            </values>
                        </set>
                    </jobs>
                </folder>
            </jobs>
        </sequential>
    </job>
</oddjob>

Note that the current interval property is not changed, so the echo job shows 'Running at 9999-12-31 00:00:00.000'.

Example

Manually rescheduling the timer. When the set job is run manually, the timer will advance to it's next scheduled slot.

<oddjob>
    <job>
        <sequential>
            <jobs>
                <scheduling:timer id="timer" xmlns:scheduling="http://rgordon.co.uk/oddjob/scheduling">
                    <schedule>
                        <schedules:daily at="23:00" xmlns:schedules="http://rgordon.co.uk/oddjob/schedules"/>
                    </schedule>
                    <clock>
                        <value value="${clock}"/>
                    </clock>
                    <job>
                        <echo id="echo">Running at ${timer.current.fromDate}</echo>
                    </job>
                </scheduling:timer>
                <folder>
                    <jobs>
                        <set id="set">
                            <values>
                                <date date="TOMORROW" key="timer.reschedule">
                                    <clock>
                                        <value value="${clock}"/>
                                    </clock>
                                </date>
                            </values>
                        </set>
                    </jobs>
                </folder>
            </jobs>
        </sequential>
    </job>
</oddjob>

Note that the unlike above, current interval property changes when the time is rescheduled.

See Also:

Serialized Form

Author:

Rob Gordon.

Field Summary

Fields inherited from class org.oddjob.scheduling.TimerBase

contextData

Fields inherited from class org.oddjob.scheduling.ScheduleBase

begun, childHelper, childStateReflector, stateHandler, stop

Constructor Summary

Constructors

Constructor and Description
Timer()

Method Summary

Modifier and Type	Method and Description
protected void	begin() Sub classes must override this to submit the first execution.
protected StateCondition	getDefaultHaltOn()
protected ResetAction	getDefaultReset()
protected IntervalTo	getLimits() Implementation provided by sub classes so limits are available in TimerBase.scheduleFrom(Date).
protected StateOperator	getStateOp() Sub classes provide the state operator that is used to calculate the subclasses completion state.
boolean	isHaltOnFailure()
boolean	isSkipMissedRuns()
void	setHaltOnFailure(boolean haltOnFailure)
void	setSkipMissedRuns(boolean skipMissedRuns)

Methods inherited from class org.oddjob.scheduling.TimerBase

CancelAndStopChild, changeStateLocked, getClock, getCurrent, getHaltOn, getLastDue, getNextDue, getReset, getSchedule, getTimeZone, handleChildState, internalSetNextDue, onReset, onStop, postStop, reschedule, reset, scheduleFrom, setClock, setHaltOn, setJob, setNextDue, setReschedule, setReset, setSchedule, setScheduleExecutorService, setTimeZone

Methods inherited from class org.oddjob.scheduling.ScheduleBase

addStructuralListener, fireDestroyedState, force, getStateChanger, hardReset, iconHelper, onDestroy, removeStructuralListener, run, softReset, stateHandler, stop

Methods inherited from class org.oddjob.framework.extend.BasePrimary

configure, getName, logger, logger, loggerName, save, setName, toString

Methods inherited from class org.oddjob.framework.extend.BaseComponent

addIconListener, addPropertyChangeListener, addStateListener, configure, destroy, firePropertyChange, getArooaSession, iconForId, initialise, lastStateEvent, onConfigured, onInitialised, removeIconListener, removePropertyChangeListener, removeStateListener, save, setArooaContext, setArooaSession

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.oddjob.Stateful

addStateListener, lastStateEvent, removeStateListener

Constructor Detail

Timer

public Timer()

Method Detail

getStateOp

protected StateOperator getStateOp()

Description copied from class: ScheduleBase

Sub classes provide the state operator that is used to calculate the subclasses completion state.

Specified by:

getStateOp in class ScheduleBase

Returns:

The operator. Must not be null.

begin

protected void begin()
              throws ComponentPersistException

Description copied from class: ScheduleBase

Sub classes must override this to submit the first execution.

Overrides:

begin in class TimerBase

Throws:

ComponentPersistException - If the scheduled time can't be saved.

setHaltOnFailure

public void setHaltOnFailure(boolean haltOnFailure)

isHaltOnFailure

public boolean isHaltOnFailure()

isSkipMissedRuns

public boolean isSkipMissedRuns()

Specified by:

isSkipMissedRuns in class TimerBase

setSkipMissedRuns

public void setSkipMissedRuns(boolean skipMissedRuns)

getLimits

protected IntervalTo getLimits()

Description copied from class: TimerBase

Implementation provided by sub classes so limits are available in TimerBase.scheduleFrom(Date).

Specified by:

getLimits in class TimerBase

Returns:

The limits, or null. Retry has limits, timer doesn't.

getDefaultHaltOn

protected StateCondition getDefaultHaltOn()

Specified by:

getDefaultHaltOn in class TimerBase

getDefaultReset

protected ResetAction getDefaultReset()

Specified by:

getDefaultReset in class TimerBase