Akka/akka.actor.typed.scaladsl/TimerScheduler

TimerScheduler

@DoNotInherit
trait TimerScheduler[T]

Support for scheduled self messages in an actor. It is used with Behaviors.withTimers. Timers are bound to the lifecycle of the actor that owns it, and thus are cancelled automatically when it is restarted or stopped.

TimerScheduler is not thread-safe, i.e. it must only be used within the actor that owns it.

Not for user extension.

Source:
TimerScheduler.scala
class Object
trait Matchable
class Any

Value members

Abstract methods

def cancel(key: Any): Unit

Cancel a timer with a given key. If canceling a timer that was already canceled, or key never was used to start a timer this operation will do nothing.

Cancel a timer with a given key. If canceling a timer that was already canceled, or key never was used to start a timer this operation will do nothing.

It is guaranteed that a message from a canceled timer, including its previous incarnation for the same key, will not be received by the actor, even though the message might already be enqueued in the mailbox when cancel is called.

Source:
TimerScheduler.scala
def cancelAll(): Unit

Cancel all timers.

Cancel all timers.

Source:
TimerScheduler.scala
def isTimerActive(key: Any): Boolean

Check if a timer with a given key is active.

Check if a timer with a given key is active.

Source:
TimerScheduler.scala
def startSingleTimer(key: Any, msg: T, delay: FiniteDuration): Unit

Start a timer that will send msg once to the self actor after the given delay.

Start a timer that will send msg once to the self actor after the given delay.

Each timer has a key and if a new timer with same key is started the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started.

Source:
TimerScheduler.scala
def startTimerAtFixedRate(key: Any, msg: T, interval: FiniteDuration): Unit

Schedules a message to be sent repeatedly to the self actor with a given frequency.

Schedules a message to be sent repeatedly to the self actor with a given frequency.

It will compensate the delay for a subsequent message if the sending of previous message was delayed more than specified. In such cases, the actual message interval will differ from the interval passed to the method.

If the execution is delayed longer than the interval, the subsequent message will be sent immediately after the prior one. This also has the consequence that after long garbage collection pauses or other reasons when the JVM was suspended all "missed" messages will be sent when the process wakes up again.

In the long run, the frequency of messages will be exactly the reciprocal of the specified interval.

Warning: startTimerAtFixedRate can result in bursts of scheduled messages after long garbage collection pauses, which may in worst case cause undesired load on the system. Therefore startTimerWithFixedDelay is often preferred.

Each timer has a key and if a new timer with same key is started the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started.

Source:
TimerScheduler.scala
def startTimerAtFixedRate(key: Any, msg: T, initialDelay: FiniteDuration, interval: FiniteDuration): Unit

Schedules a message to be sent repeatedly to the self actor with a given frequency.

Schedules a message to be sent repeatedly to the self actor with a given frequency.

It will compensate the delay for a subsequent message if the sending of previous message was delayed more than specified. In such cases, the actual message interval will differ from the interval passed to the method.

If the execution is delayed longer than the interval, the subsequent message will be sent immediately after the prior one. This also has the consequence that after long garbage collection pauses or other reasons when the JVM was suspended all "missed" messages will be sent when the process wakes up again.

In the long run, the frequency of messages will be exactly the reciprocal of the specified interval after initialDelay.

Warning: startTimerAtFixedRate can result in bursts of scheduled messages after long garbage collection pauses, which may in worst case cause undesired load on the system. Therefore startTimerWithFixedDelay is often preferred.

Each timer has a key and if a new timer with same key is started the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started.

Source:
TimerScheduler.scala
def startTimerWithFixedDelay(key: Any, msg: T, delay: FiniteDuration): Unit

Schedules a message to be sent repeatedly to the self actor with a fixed delay between messages.

Schedules a message to be sent repeatedly to the self actor with a fixed delay between messages.

It will not compensate the delay between messages if scheduling is delayed longer than specified for some reason. The delay between sending of subsequent messages will always be (at least) the given delay.

In the long run, the frequency of messages will generally be slightly lower than the reciprocal of the specified delay.

Each timer has a key and if a new timer with same key is started the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already be enqueued in the mailbox before the new timer was started.

Source:
TimerScheduler.scala
def startTimerWithFixedDelay(key: Any, msg: T, initialDelay: FiniteDuration, delay: FiniteDuration): Unit

Schedules a message to be sent repeatedly to the self actor with a fixed delay between messages after the initialDelay.

Schedules a message to be sent repeatedly to the self actor with a fixed delay between messages after the initialDelay.

It will not compensate the delay between messages if scheduling is delayed longer than specified for some reason. The delay between sending of subsequent messages will always be (at least) the given delay.

In the long run, the frequency of messages will generally be slightly lower than the reciprocal of the specified delay.

Each timer has a key and if a new timer with same key is started the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already be enqueued in the mailbox before the new timer was started.

Source:
TimerScheduler.scala

Concrete methods

def startSingleTimer(msg: T, delay: FiniteDuration): Unit

Start a timer that will send msg once to the self actor after the given delay.

Start a timer that will send msg once to the self actor after the given delay.

If a new timer is started with the same message the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started. If you do not want this, you can start start them as individual timers by specifying distinct keys.

Source:
TimerScheduler.scala
def startTimerAtFixedRate(msg: T, interval: FiniteDuration): Unit

Schedules a message to be sent repeatedly to the self actor with a given frequency.

Schedules a message to be sent repeatedly to the self actor with a given frequency.

It will compensate the delay for a subsequent message if the sending of previous message was delayed more than specified. In such cases, the actual message interval will differ from the interval passed to the method.

If the execution is delayed longer than the interval, the subsequent message will be sent immediately after the prior one. This also has the consequence that after long garbage collection pauses or other reasons when the JVM was suspended all "missed" messages will be sent when the process wakes up again.

In the long run, the frequency of messages will be exactly the reciprocal of the specified interval.

Warning: startTimerAtFixedRate can result in bursts of scheduled messages after long garbage collection pauses, which may in worst case cause undesired load on the system. Therefore startTimerWithFixedDelay is often preferred.

When a new timer is started with the same message the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started. If you do not want this, you can start start them as individual timers by specifying distinct keys.

Source:
TimerScheduler.scala
def startTimerAtFixedRate(msg: T, initialDelay: FiniteDuration, interval: FiniteDuration): Unit

Schedules a message to be sent repeatedly to the self actor with a given frequency.

Schedules a message to be sent repeatedly to the self actor with a given frequency.

It will compensate the delay for a subsequent message if the sending of previous message was delayed more than specified. In such cases, the actual message interval will differ from the interval passed to the method.

If the execution is delayed longer than the interval, the subsequent message will be sent immediately after the prior one. This also has the consequence that after long garbage collection pauses or other reasons when the JVM was suspended all "missed" messages will be sent when the process wakes up again.

In the long run, the frequency of messages will be exactly the reciprocal of the specified interval after initialDelay.

Warning: startTimerAtFixedRate can result in bursts of scheduled messages after long garbage collection pauses, which may in worst case cause undesired load on the system. Therefore startTimerWithFixedDelay is often preferred.

When a new timer is started with the same message the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started. If you do not want this, you can start start them as individual timers by specifying distinct keys.

Source:
TimerScheduler.scala
def startTimerWithFixedDelay(msg: T, delay: FiniteDuration): Unit

Schedules a message to be sent repeatedly to the self actor with a fixed delay between messages.

Schedules a message to be sent repeatedly to the self actor with a fixed delay between messages.

It will not compensate the delay between messages if scheduling is delayed longer than specified for some reason. The delay between sending of subsequent messages will always be (at least) the given delay.

In the long run, the frequency of messages will generally be slightly lower than the reciprocal of the specified delay.

When a new timer is started with the same message, the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started. If you do not want this, you can start start them as individual timers by specifying distinct keys.

Source:
TimerScheduler.scala
def startTimerWithFixedDelay(msg: T, initialDelay: FiniteDuration, delay: FiniteDuration): Unit

Schedules a message to be sent repeatedly to the self actor with a fixed delay between messages after the initialDelay.

Schedules a message to be sent repeatedly to the self actor with a fixed delay between messages after the initialDelay.

It will not compensate the delay between messages if scheduling is delayed longer than specified for some reason. The delay between sending of subsequent messages will always be (at least) the given delay.

In the long run, the frequency of messages will generally be slightly lower than the reciprocal of the specified delay.

When a new timer is started with the same message, the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started. If you do not want this, you can start start them as individual timers by specifying distinct keys.

Source:
TimerScheduler.scala

Deprecated methods

@deprecated("Use startTimerWithFixedDelay or startTimerAtFixedRate instead. This has the same semantics as ".+("startTimerAtFixedRate, but startTimerWithFixedDelay is often preferred."), since = "2.6.0")
def startPeriodicTimer(key: Any, msg: T, interval: FiniteDuration): Unit