Package org.axonframework.eventsourcing.snapshot.store

Interface SnapshotStore

All Known Implementing Classes:

AxonServerSnapshotStore, InMemorySnapshotStore

@Internal
public interface SnapshotStore

Represents storage for snapshots of event-sourced entities.

A SnapshotStore is responsible for persisting and retrieving snapshots to optimize the sourcing of entities, avoiding the need to apply all events from the beginning.

Implementations are expected to be thread-safe and fully asynchronous, returning CompletableFuture for all operations.

Since:

5.1.0

Author:

John Hendrikx

Method Summary

Modifier and Type	Method	Description
CompletableFuture<@Nullable Snapshot>	load(QualifiedName qualifiedName, Object identifier)	Loads the latest snapshot for a given name and identifier.
CompletableFuture<Void>	store(QualifiedName qualifiedName, Object identifier, Snapshot snapshot)	Persists a snapshot under the given name and identifier.

Method Details

store

CompletableFuture<Void> store(QualifiedName qualifiedName,
 Object identifier,
 Snapshot snapshot)

Persists a snapshot under the given name and identifier. This replaces any previous snapshot(s) with the same name and identifier.

This method is asynchronous and returns a CompletableFuture that completes when the snapshot has been durably stored.

Parameters:

qualifiedName - the name of the snapshot to persist, cannot be null

identifier - the identifier of the snapshot to persist, cannot be null

snapshot - the snapshot to persist, cannot be null

Returns:

a CompletableFuture that completes when the snapshot has been stored

Throws:

NullPointerException - if any argument is null

load

CompletableFuture<@Nullable Snapshot> load(QualifiedName qualifiedName,
 Object identifier)

Loads the latest snapshot for a given name and identifier.

The returned snapshot may have an older or newer version relative to what is expected. The caller is responsible for handling version compatibility or ignoring unusable snapshots.

This method is asynchronous and returns a CompletableFuture that completes with the snapshot if one exists, or null if no snapshot is available.

Parameters:

qualifiedName - the name of the snapshot, cannot be null

identifier - the identifier of the snapshot, cannot be null

Returns:

a CompletableFuture containing the snapshot, or containing null if no matching snapshot exists

Throws:

NullPointerException - if any argument is null