er.extensions.concurrency
Class ERXLongResponseTask.DefaultImplementation

java.lang.Object
  er.extensions.concurrency.ERXLongResponseTask.DefaultImplementation

All Implemented Interfaces:

ERXLongResponseTask, java.lang.Runnable

Enclosing interface:

ERXLongResponseTask

public abstract static class ERXLongResponseTask.DefaultImplementation
extends java.lang.Object
implements java.lang.Runnable, ERXLongResponseTask

Nested Class Summary

Nested classes/interfaces inherited from interface er.extensions.concurrency.ERXLongResponseTask

ERXLongResponseTask.DefaultImplementation, ERXLongResponseTask.WorkerThread

Field Summary

protected boolean	_cancelled Holds the cancel flag
protected boolean	_done Holds the done flag
protected java.lang.Exception	_exception Exception code
protected ERXLongResponse	_longResponse Refresh page that controls this task
protected java.lang.Object	_result Result code
protected java.lang.Object	_status Status code
protected java.lang.Thread	_thread Hold the thread that performs the task
org.apache.log4j.Logger	log logging support

Constructor Summary

ERXLongResponseTask.DefaultImplementation()
Constructor

Method Summary

protected void	_finishInitialization() Sets up the object.
protected com.webobjects.appserver.WOComponent	cancelPageForStatus(java.lang.Object aStatus) Override this to return a sensible page to show after the task was stopped.
protected java.lang.Exception	exception() Returns the exception that may have occurred in the run() method.
protected boolean	isCancelled() Checks if the task was stopped externally.
boolean	isDone() (non-Javadoc)
ERXLongResponse	longResponse() Returns the long response for this task.
com.webobjects.appserver.WOComponent	nextPage() Default implementation that controls the pages returned on each iteration.
protected com.webobjects.appserver.WOComponent	pageForException(java.lang.Exception exception) Override this to return an exception page suitable for the given exception.
protected com.webobjects.appserver.WOComponent	pageForResult(java.lang.Object aResult) Override this to return the page after the task was completed without beeing stopped.
abstract java.lang.Object	performAction() You need to override this and perform your long running task.
protected com.webobjects.appserver.WOComponent	refreshPageForStatus(java.lang.Object aStatus) Override this to return and modify the refresh page.
protected java.lang.Object	result() The abstract result object that has been returned by performAction().
void	run() Implementation of the Runnable interface.
protected void	setException(java.lang.Exception anObject) Use this method to flag if an exception page should get displayed after finishing the current step.
void	setLongResponse(ERXLongResponse sender) Sets the long response that controls this task.
protected void	setResult(java.lang.Object anObject) Abstract result object that will get set when the task is finished.
protected void	setStatus(java.lang.Object anObject)
void	start() Default implementation of the ERXLongResponseTask.start() method.
java.lang.Object	status() Returns a current status.
void	stop() Stops the task.

Methods inherited from class java.lang.Object

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

Field Detail

log

public org.apache.log4j.Logger log

logging support

_longResponse

protected ERXLongResponse _longResponse

Refresh page that controls this task

_status

protected java.lang.Object _status

Status code

_result

protected java.lang.Object _result

Result code

_exception

protected java.lang.Exception _exception

Exception code

_cancelled

protected boolean _cancelled

Holds the cancel flag

_done

protected boolean _done

Holds the done flag

_thread

protected java.lang.Thread _thread

Hold the thread that performs the task

Constructor Detail

ERXLongResponseTask.DefaultImplementation

public ERXLongResponseTask.DefaultImplementation()

Constructor

Method Detail

_finishInitialization

protected void _finishInitialization()

Sets up the object.

setLongResponse

public void setLongResponse(ERXLongResponse sender)

Sets the long response that controls this task.

Specified by:

setLongResponse in interface ERXLongResponseTask

longResponse

public ERXLongResponse longResponse()

Returns the long response for this task.

run

public void run()

Implementation of the Runnable interface.

Specified by:

run in interface java.lang.Runnable

status

public java.lang.Object status()

Returns a current status. This can be any object and will given again to you to divine the next step.

setStatus

protected void setStatus(java.lang.Object anObject)

exception

protected java.lang.Exception exception()

Returns the exception that may have occurred in the run() method.

setException

protected void setException(java.lang.Exception anObject)

Use this method to flag if an exception page should get displayed after finishing the current step.

Parameters:

anObject -

result

protected java.lang.Object result()

The abstract result object that has been returned by performAction().

setResult

protected void setResult(java.lang.Object anObject)

Abstract result object that will get set when the task is finished.

Parameters:

anObject -

isCancelled

protected boolean isCancelled()

Checks if the task was stopped externally.

Returns:

true if stop() was called.

isDone

public boolean isDone()

(non-Javadoc)

Specified by:

isDone in interface ERXLongResponseTask

Returns:

true if the task is still running

See Also:

ERXLongResponseTask.isDone()

stop

public void stop()

Stops the task. This just sets the cancel flag. Its up to you to check in your task if you are interruptable. So you should check isCancelled() in your performAction().

Specified by:

stop in interface ERXLongResponseTask

start

public void start()

Default implementation of the ERXLongResponseTask.start() method. Creates a new thread unless there already exists one.

Specified by:

start in interface ERXLongResponseTask

pageForException

protected com.webobjects.appserver.WOComponent pageForException(java.lang.Exception exception)

Override this to return an exception page suitable for the given exception. This implementation just re-throws the exception.

Parameters:

exception -

Returns:

page for the exceptino

refreshPageForStatus

protected com.webobjects.appserver.WOComponent refreshPageForStatus(java.lang.Object aStatus)

Override this to return and modify the refresh page. This is called while the task is still running. Note that is the place where you can call ERXLongResponse.setRefreshInterval(int) to set the next refresh time.

Parameters:

aStatus -

pageForResult

protected com.webobjects.appserver.WOComponent pageForResult(java.lang.Object aResult)

Override this to return the page after the task was completed without beeing stopped. Whether or not this counts as a success should be divined from the result object. This is the same object you return after being asked for result().

Parameters:

aResult - some result object

Returns:

result page for successfu completion

cancelPageForStatus

protected com.webobjects.appserver.WOComponent cancelPageForStatus(java.lang.Object aStatus)

Override this to return a sensible page to show after the task was stopped. The default implementation returns the refresh component's top-level page

Parameters:

aStatus - some status object

Returns:

result page for the cancelled task.

nextPage

public com.webobjects.appserver.WOComponent nextPage()

Default implementation that controls the pages returned on each iteration.

Specified by:

nextPage in interface ERXLongResponseTask

Returns:

next page according to inner status.

performAction

public abstract java.lang.Object performAction()

You need to override this and perform your long running task.

Returns:

result of performing the action