org.axonframework.eventhandling.saga.repository

Interface SagaStore<T>

Type Parameters:

T - The saga type

All Known Implementing Classes:

CachingSagaStore, InMemorySagaStore, JdbcSagaStore, JpaSagaStore, MongoSagaStore

public interface SagaStore<T>

Provides a mechanism to find, load update and delete sagas of type T from an underlying storage like a database.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	SagaStore.Entry<T> Interface describing a Saga entry fetched from a SagaStore.

Method Summary

Modifier and Type	Method and Description
void	deleteSaga(Class<? extends T> sagaType, String sagaIdentifier, Set<AssociationValue> associationValues) Deletes a Saga with given sagaType and sagaIdentifier and all its associations.
Set<String>	findSagas(Class<? extends T> sagaType, AssociationValue associationValue) Returns identifiers of saga instances of the given sagaType that have been associated with the given associationValue.
void	insertSaga(Class<? extends T> sagaType, String sagaIdentifier, T saga, TrackingToken token, Set<AssociationValue> associationValues) Adds a new Saga and its initial association values to the store.
<S extends T> SagaStore.Entry<S>	loadSaga(Class<S> sagaType, String sagaIdentifier) Loads a known saga SagaStore.Entry instance with given sagaType and unique sagaIdentifier.
void	updateSaga(Class<? extends T> sagaType, String sagaIdentifier, T saga, TrackingToken token, AssociationValues associationValues) Updates a given Saga after its state was modified.

Method Detail

findSagas

Set<String> findSagas(Class<? extends T> sagaType,
                      AssociationValue associationValue)

Returns identifiers of saga instances of the given sagaType that have been associated with the given associationValue.

Parameters:

sagaType - The type of the returned sagas

associationValue - The value that the returned sagas must be associated with

Returns:

A set of identifiers of sagas having the correct type and association value

loadSaga

<S extends T> SagaStore.Entry<S> loadSaga(Class<S> sagaType,
                                          String sagaIdentifier)

Loads a known saga SagaStore.Entry instance with given sagaType and unique sagaIdentifier.

Due to the concurrent nature of Sagas, it is not unlikely for a Saga to have ceased to exist after it has been found based on associations. Therefore, a repository should return null in case a Saga doesn't exists, as opposed to throwing an exception.

Parameters:

sagaType - The type of the returned saga entry

sagaIdentifier - The unique identifier of the returned saga entry

Returns:

The saga entry, or null if no such saga exists

deleteSaga

void deleteSaga(Class<? extends T> sagaType,
                String sagaIdentifier,
                Set<AssociationValue> associationValues)

Deletes a Saga with given sagaType and sagaIdentifier and all its associations. For convenience all known association values are passed along as well, which has the advantage that the saga store is not required to keep an index of association value to saga identifier.

Parameters:

sagaType - The type of saga to delete

sagaIdentifier - The identifier of the saga to delete

associationValues - The known associations of the saga

insertSaga

void insertSaga(Class<? extends T> sagaType,
                String sagaIdentifier,
                T saga,
                TrackingToken token,
                Set<AssociationValue> associationValues)

Adds a new Saga and its initial association values to the store. The tracking token of the event last handled by the Saga (usually the event that started the Saga) is also passed as a parameter. Note that the given token may be null if the Saga is not tracking the event store.

Parameters:

sagaType - The type of the Saga

sagaIdentifier - The identifier of the Saga

saga - The Saga instance

token - The tracking token of the event last handled by the Saga. May be null.

associationValues - The initial association values of the Saga

updateSaga

void updateSaga(Class<? extends T> sagaType,
                String sagaIdentifier,
                T saga,
                TrackingToken token,
                AssociationValues associationValues)

Updates a given Saga after its state was modified. The tracking token of the event last handled by the Saga is also passed as a parameter. Note that the given token may be null if the Saga is not tracking the event store.

Parameters:

sagaType - The type of the Saga

sagaIdentifier - The identifier of the Saga

saga - The Saga instance

token - The tracking token of the event last handled by the Saga. May be null.

associationValues - The initial association values of the Saga