Package com.inductiveautomation.ignition.common.execution

Class PollingFuture<V>

java.lang.Object

com.inductiveautomation.ignition.common.lifecycle.AbstractLifecycle

com.inductiveautomation.ignition.common.execution.PollingFuture<V>

Direct Known Subclasses:

PerspectivePollingFuture

public class PollingFuture<V>
extends AbstractLifecycle

Scaffolding for managing the fetching of a completable future that may need to poll or be executed on-demand.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static enum	PollingFuture.State

Field Summary

Fields

Modifier and Type	Field	Description
protected static final LoggerEx	LOG

Constructor Summary

Constructors

Constructor	Description
PollingFuture(ScheduledExecutorService scheduler, ExecutorService executor, Supplier<CompletableFuture<V>> fetch, BiConsumer<V,Throwable> whenComplete, long rate, TimeUnit rateTimeUnit, String diagnosticId)

Method Summary

Modifier and Type	Method	Description
protected long	getInitialRate()	Default implementation returns the rate from the constructor, but provides a place for subclasses to re-define the rate on startup if necessary.
long	getRateMillis()
protected void	onShutdown()
protected void	onStartup()
void	setRate(long rate, TimeUnit unit)
void	submitIfIdle()	Submits the task immediately if currently idle or scheduled.

Methods inherited from class com.inductiveautomation.ignition.common.lifecycle.AbstractLifecycle

isRunning, shutdown, startup

Methods inherited from class java.lang.Object

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

Field Details

LOG

protected static final LoggerEx LOG

Constructor Details

PollingFuture

public PollingFuture(ScheduledExecutorService scheduler,
 ExecutorService executor,
 Supplier<CompletableFuture<V>> fetch,
 BiConsumer<V,Throwable> whenComplete,
 long rate,
 TimeUnit rateTimeUnit,
 String diagnosticId)

Parameters:

scheduler - No blocking work will be done on this scheduler

executor - Value delivery will be done on this executor

fetch - Fetch the next value. Don't block.

whenComplete - Callback for when the value is received. May block. Will be called on the executor.

rate - If positive, the task will be executed once on startup, and then repeatedly with this amount of time as a delay between executions. If zero or less, will be executed once on startup, and again whenever submitIfIdle() is called.

rateTimeUnit - Time unit for the rate.

diagnosticId - Will be set during task execution using MDC as "task-id" key

Method Details

submitIfIdle

public void submitIfIdle()

Submits the task immediately if currently idle or scheduled.

getInitialRate

protected long getInitialRate()

Default implementation returns the rate from the constructor, but provides a place for subclasses to re-define the rate on startup if necessary.

onStartup

protected void onStartup()

Specified by:

onStartup in class AbstractLifecycle

onShutdown

protected void onShutdown()

Specified by:

onShutdown in class AbstractLifecycle

setRate

public void setRate(long rate,
 TimeUnit unit)

getRateMillis

public long getRateMillis()