org.oddjob.state

Class EqualsState

java.lang.Object

org.oddjob.framework.extend.BaseComponent

org.oddjob.framework.extend.BasePrimary

org.oddjob.framework.extend.StructuralJob<Stateful>

org.oddjob.state.EqualsState

All Implemented Interfaces:

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

public class EqualsState
extends StructuralJob<Stateful>
implements Stoppable

Description

Runs it's child job and then compares the state of the child job to the given state. It's own state is complete if the states match, incomplete otherwise.

This job is probably most useful in it's 'not equals' form - i.e. to check when something hasn't completed.

Example

COMPLETE when the child job isn't complete. This example demonstrates how the state:equals job can be used to reverse the meaning of the exists job. A request to shutdown a database may complete asynchronously, and the only way to tell if shutdown is complete is to check that the Database's lock file has be removed. This example demonstrates how Oddjob can check for this situation before attempting to back up the database.

<oddjob id="this">
    <job>
        <scheduling:retry name="Database Backup" xmlns:scheduling="http://rgordon.co.uk/oddjob/scheduling">
            <schedule>
                <schedules:interval interval="00:00:02" xmlns:schedules="http://rgordon.co.uk/oddjob/schedules"/>
            </schedule>
            <job>
                <sequential id="db-backup">
                    <jobs>
                        <state:equals state="!COMPLETE" xmlns:state="http://rgordon.co.uk/oddjob/state">
                            <job>
                                <state:resets harden="true">
                                    <job>
                                        <exists file="${db.lock.file}"/>
                                    </job>
                                </state:resets>
                            </job>
                        </state:equals>
                        <echo>Backing up the Database...</echo>
                    </jobs>
                </sequential>
            </job>
        </scheduling:retry>
    </job>
</oddjob>

See Also:

Serialized Form

Author:

Rob Gordon

Field Summary

Fields inherited from class org.oddjob.framework.extend.StructuralJob

childHelper, destroy, stop, structuralState

Constructor Summary

Constructors

Constructor and Description
EqualsState()

Method Summary

Modifier and Type	Method and Description
protected void	execute() Execute this job.
protected StateOperator	getInitialStateOp() Subclasses must provide the StateOperator that will decide how to evaluate the children's state.
StateCondition	getState()
void	setJob(Stateful job)
void	setState(StateCondition state)

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

addStructuralListener, fireDestroyedState, force, getStateChanger, hardReset, iconHelper, isStop, onDestroy, onHardReset, onReset, onSoftReset, onStop, postStop, removeStructuralListener, run, softReset, startChildStateReflector, stateHandler, stop, stopChildStateReflector

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.Stoppable

stop

Methods inherited from interface org.oddjob.Stateful

addStateListener, lastStateEvent, removeStateListener

Constructor Detail

EqualsState

public EqualsState()

Method Detail

getState

public StateCondition getState()

setState

public void setState(StateCondition state)

getInitialStateOp

protected StateOperator getInitialStateOp()

Description copied from class: StructuralJob

Subclasses must provide the StateOperator that will decide how to evaluate the children's state.

Specified by:

getInitialStateOp in class StructuralJob<Stateful>

Returns:

A State Operator. Must not be null.

setJob

public void setJob(Stateful job)

Property: job

Description: The job to run who's state will be compared.

Required: Yes.

execute

protected void execute()
                throws java.lang.Throwable

Description copied from class: StructuralJob

Execute this job.

Specified by:

execute in class StructuralJob<Stateful>

Throws:

java.lang.Exception - If the unexpected occurs.

java.lang.Throwable