org.imajine.image.processor

Class ImagingTask

java.lang.Object

org.imajine.image.processor.ImagingTask

All Implemented Interfaces:

Serializable

public abstract class ImagingTask
extends Object
implements Serializable

Encapsulates an unit of image processing. Concrete implementations of this class MUST BE serializable.

Version:

$Id: ImagingTask.java,v 20e39e8c9fac 2012/02/02 16:35:02 fabrizio $

Author:

Fabrizio Giudici

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
long	latestExecutionTime

Constructor Summary

Constructors

Constructor and Description
ImagingTask() For serialization.
ImagingTask(String name, int loggingId) Creates a new instance of ImagingTask.

Method Summary

Methods

Modifier and Type	Method and Description
void	addStatisticsSample(String name, long value)
void	dispose() Subclasses should release all the allocated resources when this method is called.
boolean	equals(Object object) See the comment about uniqueId.
void	execute() Executes the task.
protected <T extends org.imajine.image.op.Operation> T	execute(org.imajine.image.EditableImage image, T operation, String operationName) Executes an operation adding the elapsed time to the statistics.
protected org.imajine.image.EditableImage	execute2(org.imajine.image.EditableImage image, org.imajine.image.op.Operation operation, String operationName) Executes an operation adding the elapsed time to the statistics.
protected org.imajine.image.EditableImage	execute2AndDispose(org.imajine.image.EditableImage image, org.imajine.image.op.Operation operation, String operationName) The same as execute2(), but the operand image is disposed before returning.
protected <T extends org.imajine.image.op.Operation> T	executeAndDispose(org.imajine.image.EditableImage image, T operation, String operationName) The same as execute(), but the operand image is disposed before returning.
Serializable	getId() Returns the unique id of this task.
String	getName() Returns the name of this task.
org.imajine.image.EditableImage	getResult() Returns the result of this task.
Statistics	getStatistics() Returns the statistics collected by this task.
Throwable	getThrowable() If the task ended with an error, a Throwable is returned by this method.
int	hashCode() See the comment about uniqueId.
boolean	isRemoteExecutionOk() If this method return true (the default), this task can be executed remotely.
void	prepare(ImagingTaskProcessor processor) This method is performed in a local context before the task is scheduled to run - that is, this method is performed in a serialized fashion, possibly on a single computing node (depending on the processing engine).
protected void	registerTime(String name, org.imajine.image.EditableImage image) Updates statistics about execution time, about the latest performed operation on the given image.
protected abstract void	run() Concrete implementations should provide the task core in this method.
protected void	setResult(org.imajine.image.EditableImage result)
void	setThrowable(Throwable throwable)
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

latestExecutionTime

public long latestExecutionTime

Constructor Detail

ImagingTask

public ImagingTask()

For serialization.

ImagingTask

public ImagingTask(String name,
           int loggingId)

Creates a new instance of ImagingTask. Subclasses must *not* perform any initialization here: they should use prepare() instead. This constructor must return very quickly.

Method Detail

getName

public String getName()

Returns the name of this task.

Returns:

the task name

getId

public Serializable getId()

Returns the unique id of this task.

Returns:

the task id

prepare

public void prepare(ImagingTaskProcessor processor)
             throws Exception

This method is performed in a local context before the task is scheduled to run - that is, this method is performed in a serialized fashion, possibly on a single computing node (depending on the processing engine). Subclasses can override this method for customizing the behaviour (that must not be computing intensive). The processor parameter can be used to query some properties of the ImagingTaskProcessor that could be used for alternate preparing strategies. The super method must be always called.

Parameters:

processor - the processor

Throws:

Exception

run

protected abstract void run()
                     throws Exception

Concrete implementations should provide the task core in this method. This method is performed in a distributed context, if available.

Throws:

Exception

getResult

public final org.imajine.image.EditableImage getResult()

Returns the result of this task. Must be implemented by subclasses.

Returns:

the result

setResult

protected final void setResult(org.imajine.image.EditableImage result)

getThrowable

public Throwable getThrowable()

If the task ended with an error, a Throwable is returned by this method.

Returns:

the throwable

setThrowable

public void setThrowable(Throwable throwable)

isRemoteExecutionOk

public boolean isRemoteExecutionOk()

If this method return true (the default), this task can be executed remotely. Otherwise it will be scheduled on the local node. Usually tasks which computation time is very quick and much shorter than the overhead to serialize data back and forth should return false.

Returns:

true if the task can be scheduled remotely

getStatistics

public Statistics getStatistics()

Returns the statistics collected by this task.

Returns:

the statistics

dispose

public void dispose()

Subclasses should release all the allocated resources when this method is called.

toString

public final String toString()

Overrides:

toString in class Object

hashCode

public final int hashCode()

See the comment about uniqueId.

Overrides:

hashCode in class Object

equals

public final boolean equals(Object object)

See the comment about uniqueId.

Overrides:

equals in class Object

execute

public final void execute()

Executes the task. This method is only called by the framework.

addStatisticsSample

public void addStatisticsSample(String name,
                       long value)

registerTime

protected void registerTime(String name,
                org.imajine.image.EditableImage image)

Updates statistics about execution time, about the latest performed operation on the given image.

Parameters:

name - the statistics name

image - the image

execute

protected <T extends org.imajine.image.op.Operation> T execute(org.imajine.image.EditableImage image,
                                                   T operation,
                                                   String operationName)

Executes an operation adding the elapsed time to the statistics.

Parameters:

image - the image to process

operation - the operation to execute

operationName - the name used for the statistics

Returns:

the operation (as a convenience in case it carries results)

executeAndDispose

protected <T extends org.imajine.image.op.Operation> T executeAndDispose(org.imajine.image.EditableImage image,
                                                             T operation,
                                                             String operationName)

The same as execute(), but the operand image is disposed before returning.

Parameters:

image - the image to process

operation - the operation to execute

operationName - the name used for the statistics

Returns:

the operation (as a convenience in case it carries results)

execute2

protected org.imajine.image.EditableImage execute2(org.imajine.image.EditableImage image,
                                       org.imajine.image.op.Operation operation,
                                       String operationName)

Executes an operation adding the elapsed time to the statistics.

Parameters:

image - the image to process

operation - the operation to execute

operationName - the name used for the statistics

Returns:

the result

execute2AndDispose

protected org.imajine.image.EditableImage execute2AndDispose(org.imajine.image.EditableImage image,
                                                 org.imajine.image.op.Operation operation,
                                                 String operationName)

The same as execute2(), but the operand image is disposed before returning.

Parameters:

image - the image to process

operation - the operation to execute

operationName - the name used for the statistics

Returns:

the result