Package org.occurrent.subscription.blocking.durable.catchup

Interface SubscriptionPositionStorageConfig

All Known Subinterfaces:

SubscriptionPositionStorageConfig.UseSubscriptionPositionInStorage

All Known Implementing Classes:

SubscriptionPositionStorageConfig.DontUseSubscriptionPositionInStorage, SubscriptionPositionStorageConfig.PersistSubscriptionPositionDuringCatchupPhase, SubscriptionPositionStorageConfig.UseOnlySubscriptionPositionInStorage

public sealed interface SubscriptionPositionStorageConfig
permits SubscriptionPositionStorageConfig.DontUseSubscriptionPositionInStorage, SubscriptionPositionStorageConfig.UseSubscriptionPositionInStorage

Configures if and how subscription position persistence should be handled during the catch-up phase.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static final record	SubscriptionPositionStorageConfig.DontUseSubscriptionPositionInStorage
static final record	SubscriptionPositionStorageConfig.PersistSubscriptionPositionDuringCatchupPhase
static final record	SubscriptionPositionStorageConfig.UseOnlySubscriptionPositionInStorage
static interface	SubscriptionPositionStorageConfig.UseSubscriptionPositionInStorage

Method Summary

Static Methods

Modifier and Type	Method	Description
static SubscriptionPositionStorageConfig.DontUseSubscriptionPositionInStorage	dontUseSubscriptionPositionStorage()	Don't use a subscription position storage.
static SubscriptionPositionStorageConfig.UseSubscriptionPositionInStorage	useSubscriptionPositionStorage(SubscriptionPositionStorage storage)	Use a specific storage instance.

Method Details

dontUseSubscriptionPositionStorage

static SubscriptionPositionStorageConfig.DontUseSubscriptionPositionInStorage dontUseSubscriptionPositionStorage()

Don't use a subscription position storage. The catch-up subscription will start from beginning of time each time it is started (for example each time the application is restarted).

Returns:

An instance of SubscriptionPositionStorageConfig.DontUseSubscriptionPositionInStorage.

useSubscriptionPositionStorage

static SubscriptionPositionStorageConfig.UseSubscriptionPositionInStorage useSubscriptionPositionStorage(SubscriptionPositionStorage storage)

Use a specific storage instance. The catch-up subscription will use this storage to check if a position has already been persisted, and if so the catch-up subscription, will continue from this position. The catch-up subscription will delegate to the wrapping subscription if the position belongs to it.

This is really useful if you want to start-off with a catch-up subscription but then automatically continue with from the wrapped subscription position once the events have caught up.

Note that if this setting is not combined with SubscriptionPositionStorageConfig.UseSubscriptionPositionInStorage.andPersistSubscriptionPositionDuringCatchupPhaseForEveryNEvents(int) or SubscriptionPositionStorageConfig.UseSubscriptionPositionInStorage.andPersistSubscriptionPositionDuringCatchupPhaseWhen(Predicate) the subscription position is will not be stored during the catch-up phase. This means that if the application crashes during catch-up it'll restart from the beginning when the application is restarted. Combine this settings with any of the two methods defined above to alleviate this, if deemed required.

Parameters:

storage - The storage to use. Must be the same instance as used by the wrapped subscription in order to allow continuing from the subscription position on application restart.

Returns:

A SubscriptionPositionStorageConfig.UseSubscriptionPositionInStorage instance.