akka.persistence

Interface PersistentView

All Superinterfaces:

Actor, ActorLogging, PersistenceIdentity, PersistenceRecovery, RequiresMessageQueue<DequeBasedMessageQueueSemantics>, Snapshotter, Stash, StashFactory, StashSupport, UnrestrictedStash

All Known Implementing Classes:

AbstractPersistentView, UntypedPersistentView

Deprecated.

use Persistence Query instead. Since 2.4.

public interface PersistentView
extends Actor, Snapshotter, Stash, StashFactory, PersistenceIdentity, PersistenceRecovery, ActorLogging

A view replicates the persistent message stream of a PersistentActor. Implementation classes receive the message stream directly from the Journal. These messages can be processed to update internal state in order to maintain an (eventual consistent) view of the state of the corresponding persistent actor. A persistent view can also run on a different node, provided that a replicated journal is used.

Implementation classes refer to a persistent actors' message stream by implementing persistenceId with the corresponding (shared) identifier value.

Views can also store snapshots of internal state by calling autoUpdate(). The snapshots of a view are independent of those of the referenced persistent actor. During recovery, a saved snapshot is offered to the view with a SnapshotOffer message, followed by replayed messages, if any, that are younger than the snapshot. Default is to offer the latest saved snapshot.

By default, a view automatically updates itself with an interval returned by autoUpdateInterval. This method can be overridden by implementation classes to define a view instance-specific update interval. The default update interval for all views of an actor system can be configured with the akka.persistence.view.auto-update-interval configuration key. Applications may trigger additional view updates by sending the view Update requests. See also methods

- autoUpdate() for turning automated updates on or off - autoUpdateReplayMax() for limiting the number of replayed messages per view update cycle

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	PersistentView.ScheduledUpdate Deprecated.
static class	PersistentView.ScheduledUpdate$ Deprecated.
static interface	PersistentView.State Deprecated.

Nested classes/interfaces inherited from interface akka.actor.Actor

Actor.emptyBehavior$, Actor.ignoringBehavior$

Method Summary

Modifier and Type	Method and Description
void	aroundPreStart() Deprecated. INTERNAL API.
void	aroundReceive(scala.PartialFunction<java.lang.Object,scala.runtime.BoxedUnit> receive, java.lang.Object message) Deprecated. INTERNAL API.
boolean	autoUpdate() Deprecated. If true, this view automatically updates itself with an interval specified by autoUpdateInterval.
scala.concurrent.duration.FiniteDuration	autoUpdateInterval() Deprecated. The interval for automated updates.
long	autoUpdateReplayMax() Deprecated. The maximum number of messages to replay per update.
void	changeState(PersistentView.State state) Deprecated.
java.lang.Object	ignoreRemainingReplay(java.lang.Throwable cause) Deprecated.
boolean	isPersistent() Deprecated. If true, the currently processed message was persisted (is sent from the Journal).
ActorRef	journal() Deprecated.
long	lastSequenceNr() Deprecated. Highest received sequence number so far or 0L if this actor hasn't replayed any persistent events yet.
void	onReplayError(java.lang.Throwable cause) Deprecated. Called whenever a message replay fails.
void	postStop() Deprecated. User overridable callback.
void	preRestart(java.lang.Throwable reason, scala.Option<java.lang.Object> message) Deprecated. User overridable callback: '''By default it disposes of all children and then calls postStop().'''
void	preStart() Deprecated. Triggers an initial recovery, starting form a snapshot, if any, and replaying at most autoUpdateReplayMax messages (following that snapshot).
Recovery	recovery() Deprecated. Called when the persistent actor is started for the first time.
java.lang.Object	recoveryStarted(long replayMax) Deprecated.
java.lang.Object	replayStarted(boolean await) Deprecated.
void	setLastSequenceNr(long value) Deprecated.
long	snapshotSequenceNr() Deprecated. Returns lastSequenceNr.
ActorRef	snapshotStore() Deprecated. Snapshot store plugin actor.
java.lang.String	snapshotterId() Deprecated. Returns viewId.
void	startRecovery(Recovery recovery) Deprecated.
void	updateLastSequenceNr(PersistentRepr persistent) Deprecated.
java.lang.String	viewId() Deprecated. View id is used as identifier for snapshots performed by this PersistentView.

Methods inherited from interface akka.persistence.Snapshotter

deleteSnapshot, deleteSnapshots, loadSnapshot, saveSnapshot

Methods inherited from interface akka.actor.Actor

aroundPostRestart, aroundPostStop, aroundPreRestart, context, postRestart, receive, self, sender, supervisorStrategy, unhandled

Methods inherited from interface akka.actor.StashSupport

actorCell, clearStash, context, enqueueFirst, mailbox, prepend, self, stash, unstash, unstashAll, unstashAll

Methods inherited from interface akka.actor.StashFactory

createStash

Methods inherited from interface akka.persistence.PersistenceIdentity

journalPluginId, persistenceId, snapshotPluginId

Methods inherited from interface akka.actor.ActorLogging

log

Method Detail

journal

ActorRef journal()

Deprecated.

snapshotStore

ActorRef snapshotStore()

Deprecated.

Description copied from interface: Snapshotter

Snapshot store plugin actor.

Specified by:

snapshotStore in interface Snapshotter

viewId

java.lang.String viewId()

Deprecated.

View id is used as identifier for snapshots performed by this PersistentView. This allows the View to keep separate snapshots of data than the PersistentActor originating the message stream.

The usual case is to have a *different* id set as viewId than persistenceId, although it is possible to share the same id with an PersistentActor - for example to decide about snapshots based on some average or sum, calculated by this view.

Example:

    class SummingView extends PersistentView {
      override def persistenceId = "count-123"
      override def viewId        = "count-123-sum" // this view is performing summing,
                                                   // so this view's snapshots reside under the "-sum" suffixed id

      // ...
    }
 

Returns:

(undocumented)

snapshotterId

java.lang.String snapshotterId()

Deprecated.

Returns viewId.

Specified by:

snapshotterId in interface Snapshotter

Returns:

(undocumented)

isPersistent

boolean isPersistent()

Deprecated.

If true, the currently processed message was persisted (is sent from the Journal). If false, the currently processed message comes from another actor (from "user-land").

Returns:

(undocumented)

autoUpdate

boolean autoUpdate()

Deprecated.

If true, this view automatically updates itself with an interval specified by autoUpdateInterval. If false, applications must explicitly update this view by sending Update requests. The default value can be configured with the akka.persistence.view.auto-update configuration key. This method can be overridden by implementation classes to return non-default values.

Returns:

(undocumented)

autoUpdateInterval

scala.concurrent.duration.FiniteDuration autoUpdateInterval()

Deprecated.

The interval for automated updates. The default value can be configured with the akka.persistence.view.auto-update-interval configuration key. This method can be overridden by implementation classes to return non-default values.

Returns:

(undocumented)

autoUpdateReplayMax

long autoUpdateReplayMax()

Deprecated.

The maximum number of messages to replay per update. The default value can be configured with the akka.persistence.view.auto-update-replay-max configuration key. This method can be overridden by implementation classes to return non-default values.

Returns:

(undocumented)

lastSequenceNr

long lastSequenceNr()

Deprecated.

Highest received sequence number so far or 0L if this actor hasn't replayed any persistent events yet.

Returns:

(undocumented)

snapshotSequenceNr

long snapshotSequenceNr()

Deprecated.

Returns lastSequenceNr.

Specified by:

snapshotSequenceNr in interface Snapshotter

Returns:

(undocumented)

setLastSequenceNr

void setLastSequenceNr(long value)

Deprecated.

updateLastSequenceNr

void updateLastSequenceNr(PersistentRepr persistent)

Deprecated.

recovery

Recovery recovery()

Deprecated.

Description copied from interface: PersistenceRecovery

Called when the persistent actor is started for the first time. The returned Recovery object defines how the Actor will recover its persistent state before handling the first incoming message.

To skip recovery completely return Recovery.none.

Specified by:

recovery in interface PersistenceRecovery

Returns:

(undocumented)

preStart

void preStart()

Deprecated.

Triggers an initial recovery, starting form a snapshot, if any, and replaying at most autoUpdateReplayMax messages (following that snapshot).

Specified by:

preStart in interface Actor

startRecovery

void startRecovery(Recovery recovery)

Deprecated.

aroundReceive

void aroundReceive(scala.PartialFunction<java.lang.Object,scala.runtime.BoxedUnit> receive,
                   java.lang.Object message)

Deprecated.

INTERNAL API.

Specified by:

aroundReceive in interface Actor

Parameters:

receive - current behavior.

message - current message.

aroundPreStart

void aroundPreStart()

Deprecated.

INTERNAL API.

Specified by:

aroundPreStart in interface Actor

preRestart

void preRestart(java.lang.Throwable reason,
                scala.Option<java.lang.Object> message)

Deprecated.

Description copied from interface: Actor

User overridable callback: '''By default it disposes of all children and then calls postStop().'''

Specified by:

preRestart in interface Actor

Specified by:

preRestart in interface UnrestrictedStash

Parameters:

reason - the Throwable that caused the restart to happen

message - optionally the current message the actor processed when failing, if applicable

Is called on a crashed Actor right BEFORE it is restarted to allow clean up of resources before Actor is terminated.

postStop

void postStop()

Deprecated.

Description copied from interface: Actor

User overridable callback.

Is called asynchronously after 'actor.stop()' is invoked. Empty default implementation.

Specified by:

postStop in interface Actor

Specified by:

postStop in interface UnrestrictedStash

onReplayError

void onReplayError(java.lang.Throwable cause)

Deprecated.

Called whenever a message replay fails. By default it logs the error. Subclass may override to customize logging. The PersistentView will not stop or throw exception due to this. It will try again on next update.

Parameters:

cause - (undocumented)

changeState

void changeState(PersistentView.State state)

Deprecated.

recoveryStarted

java.lang.Object recoveryStarted(long replayMax)

Deprecated.

replayStarted

java.lang.Object replayStarted(boolean await)

Deprecated.

ignoreRemainingReplay

java.lang.Object ignoreRemainingReplay(java.lang.Throwable cause)

Deprecated.