org.apache.flink.streaming.runtime.tasks

Class SystemProcessingTimeService

java.lang.Object

org.apache.flink.streaming.runtime.tasks.SystemProcessingTimeService

All Implemented Interfaces:

ProcessingTimeService, TimerService

@Internal
public class SystemProcessingTimeService
extends Object
implements TimerService

A TimerService which assigns as current processing time the result of calling System.currentTimeMillis() and registers timers using a ScheduledThreadPoolExecutor.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.flink.api.common.operators.ProcessingTimeService

ProcessingTimeService.ProcessingTimeCallback

Method Summary

Modifier and Type	Method and Description
protected void	finalize()
long	getCurrentProcessingTime() Returns the current processing time.
boolean	isTerminated() Returns true if the service has been shut down, false otherwise.
CompletableFuture<Void>	quiesce() This method puts the service into a state where it does not register new timers, but returns for each call to ProcessingTimeService.registerTimer(long, org.apache.flink.api.common.operators.ProcessingTimeService.ProcessingTimeCallback) or ProcessingTimeService.scheduleAtFixedRate(org.apache.flink.api.common.operators.ProcessingTimeService.ProcessingTimeCallback, long, long) a "mock" future and the "mock" future will be never completed.
ScheduledFuture<?>	registerTimer(long timestamp, ProcessingTimeService.ProcessingTimeCallback callback) Registers a task to be executed no sooner than time timestamp, but without strong guarantees of order.
ScheduledFuture<?>	scheduleAtFixedRate(ProcessingTimeService.ProcessingTimeCallback callback, long initialDelay, long period) Registers a task to be executed repeatedly at a fixed rate.
ScheduledFuture<?>	scheduleWithFixedDelay(ProcessingTimeService.ProcessingTimeCallback callback, long initialDelay, long period) Registers a task to be executed repeatedly with a fixed delay.
void	shutdownService() Shuts down and clean up the timer service provider hard and immediately.
boolean	shutdownServiceUninterruptible(long timeoutMs) Shuts down and clean up the timer service provider hard and immediately.

Methods inherited from class java.lang.Object

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

Method Detail

getCurrentProcessingTime

public long getCurrentProcessingTime()

Description copied from interface: ProcessingTimeService

Returns the current processing time.

Specified by:

getCurrentProcessingTime in interface ProcessingTimeService

registerTimer

public ScheduledFuture<?> registerTimer(long timestamp,
                                        ProcessingTimeService.ProcessingTimeCallback callback)

Registers a task to be executed no sooner than time timestamp, but without strong guarantees of order.

Specified by:

registerTimer in interface ProcessingTimeService

Parameters:

timestamp - Time when the task is to be enabled (in processing time)

callback - The task to be executed

Returns:

The future that represents the scheduled task. This always returns some future, even if the timer was shut down

scheduleAtFixedRate

public ScheduledFuture<?> scheduleAtFixedRate(ProcessingTimeService.ProcessingTimeCallback callback,
                                              long initialDelay,
                                              long period)

Description copied from interface: ProcessingTimeService

Registers a task to be executed repeatedly at a fixed rate.

This call behaves similar to ScheduledExecutor.scheduleAtFixedRate(Runnable, long, long, TimeUnit).

Parameters:

callback - to be executed after the initial delay and then after each period

initialDelay - initial delay to start executing callback

period - after the initial delay after which the callback is executed

Returns:

Scheduled future representing the task to be executed repeatedly

scheduleWithFixedDelay

public ScheduledFuture<?> scheduleWithFixedDelay(ProcessingTimeService.ProcessingTimeCallback callback,
                                                 long initialDelay,
                                                 long period)

Description copied from interface: ProcessingTimeService

Registers a task to be executed repeatedly with a fixed delay.

This call behaves similar to ScheduledExecutor.scheduleWithFixedDelay(Runnable, long, long, TimeUnit).

Parameters:

callback - to be executed after the initial delay and then after each period

initialDelay - initial delay to start executing callback

period - after the initial delay after which the callback is executed

Returns:

Scheduled future representing the task to be executed repeatedly

isTerminated

public boolean isTerminated()

Description copied from interface: TimerService

Returns true if the service has been shut down, false otherwise.

Specified by:

isTerminated in interface TimerService

quiesce

public CompletableFuture<Void> quiesce()

Description copied from interface: ProcessingTimeService

This method puts the service into a state where it does not register new timers, but returns for each call to ProcessingTimeService.registerTimer(long, org.apache.flink.api.common.operators.ProcessingTimeService.ProcessingTimeCallback) or ProcessingTimeService.scheduleAtFixedRate(org.apache.flink.api.common.operators.ProcessingTimeService.ProcessingTimeCallback, long, long) a "mock" future and the "mock" future will be never completed. Furthermore, the timers registered before are prevented from firing, but the timers in running are allowed to finish.

If no timer is running, the quiesce-completed future is immediately completed and returned. Otherwise, the future returned will be completed when all running timers have finished.

shutdownService

public void shutdownService()

Description copied from interface: TimerService

Shuts down and clean up the timer service provider hard and immediately. This does not wait for any timer to complete. Any further call to ProcessingTimeService.registerTimer(long, ProcessingTimeCallback) will result in a hard exception.

Specified by:

shutdownService in interface TimerService

shutdownServiceUninterruptible

public boolean shutdownServiceUninterruptible(long timeoutMs)

Description copied from interface: TimerService

Shuts down and clean up the timer service provider hard and immediately. This does not wait for any timer to complete. Any further call to ProcessingTimeService.registerTimer(long, ProcessingTimeCallback) will result in a hard exception. This call cannot be interrupted and will block until the shutdown is completed or the timeout is exceeded.

Specified by:

shutdownServiceUninterruptible in interface TimerService

Parameters:

timeoutMs - timeout for blocking on the service shutdown in milliseconds.

Returns:

returns true iff the shutdown was completed.

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable