Package org.openrefine.runners.local.pll.util

Class TaskSignalling

java.lang.Object

org.openrefine.runners.local.pll.util.TaskSignalling

public class TaskSignalling
extends Object

Utility class for a future and the underlying thread to communicate about pause and resume actions from the user, as well as reporting progress. The computing thread is supposed to regularly call yield() when it makes sense for it to pause its work if needed.

Constructor Summary

Constructors

Constructor	Description
TaskSignalling(long elementsToProcess)

Method Summary

Modifier and Type	Method	Description
void	addProcessedElements(long processedElements)	Method to be called by the computing thread after processing a bunch of elements, so that progress is updated.
int	getProgress()	Retrieves the current progress of the task.
boolean	isPaused()	Checks whether the thread is currently meant to be paused.
void	pause()	Instruct the computing thread to pause its work.
void	registerProgressReporter(ProgressReporter reporter)	Adds a progress reporter which should be notified whenever the progress of this task changes.
void	resume()	Instruct the computing thread to resume its work if it was paused.
void	setFullProgress()	Mark this task as fully done.
<T> CloseableIterator<T>	wrapStream(CloseableIterator<T> stream, int reportBatchSize, int reportOffset)	Wraps a stream by updating the progress reporter when it is iterated from.
void	yield()	Method to be called by the computing thread at various points when it makes sense for it to pause its work.

Methods inherited from class java.lang.Object

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

Constructor Detail

TaskSignalling

public TaskSignalling(long elementsToProcess)

Method Detail

pause

public void pause()

Instruct the computing thread to pause its work. This will only happen once the computing thread calls yield().

resume

public void resume()

Instruct the computing thread to resume its work if it was paused.

isPaused

public boolean isPaused()

Checks whether the thread is currently meant to be paused.

registerProgressReporter

public void registerProgressReporter(ProgressReporter reporter)

Adds a progress reporter which should be notified whenever the progress of this task changes.

getProgress

public int getProgress()

Retrieves the current progress of the task.

yield

public void yield()
           throws InterruptedException

Method to be called by the computing thread at various points when it makes sense for it to pause its work.

Throws:

InterruptedException - thrown when the waiting stopped because the thread was interrupted (meaning that the task is canceled)

addProcessedElements

public void addProcessedElements(long processedElements)

Method to be called by the computing thread after processing a bunch of elements, so that progress is updated.

setFullProgress

public void setFullProgress()

Mark this task as fully done.

wrapStream

public <T> CloseableIterator<T> wrapStream(CloseableIterator<T> stream,
                                           int reportBatchSize,
                                           int reportOffset)

Wraps a stream by updating the progress reporter when it is iterated from. It also checks if the thread should be paused after processing each element.

Type Parameters:

T -

Parameters:

stream - the stream to wrap

reportBatchSize - the number of elements to wait for before updating the progress object

reportOffset - the offset at which to start in the above batch

Returns: