/**
* 根据聚合标识符和 指定 版本加载 聚合
*
* @param aggregateIdentifier the identifier of the aggregate to load
* @param expectedVersion The expected version of the loaded aggregate
* @return the fully initialized aggregate
*/
@Override
protected T doLoad(ID aggregateIdentifier, final Long expectedVersion) {
AggregateEventStream events = null;
AggregateEventStream originalStream = null;
try {
try {
events = AggregateEventStore.readEvents(getTypeIdentifier(), aggregateIdentifier);
} catch (EventStreamNotFoundException e) {
throw new AggregateNotFoundException(aggregateIdentifier, "The aggregate was not found", e);
}
originalStream = events;
for (EventStreamDecorator decorator : eventStreamDecorators) {
events = decorator.decorateForRead(getTypeIdentifier(), aggregateIdentifier, events);
}
final T aggregate = aggregateFactory.createAggregate(aggregateIdentifier, events.peek());
List<AggregateEvent> unseenEvents = new ArrayList<AggregateEvent>();
aggregate.initializeState(new CapturingEventStream(events, unseenEvents, expectedVersion));
if (aggregate.isDeleted()) {
throw new AggregateDeletedException(aggregateIdentifier);
}
CurrentUnitOfWork.get()
.registerListener(new ConflictResolvingListener(aggregate, unseenEvents));
return aggregate;
} finally {
IOUtils.closeQuietlyIfCloseable(events);
// if a decorator doesn't implement closeable, we still want to be sure we close the original
// stream
IOUtils.closeQuietlyIfCloseable(originalStream);
}
}
private void removeEntry(final String sagaIdentifier, final Map<String, ?> sagaMap) {
if (!CurrentUnitOfWork.isStarted()) {
sagaMap.remove(sagaIdentifier);
} else {
CurrentUnitOfWork.get()
.registerListener(
new UnitOfWorkListenerAdapter() {
@Override
public void afterCommit(UnitOfWork unitOfWork) {
sagaMap.remove(sagaIdentifier);
}
});
}
}
private void doReleaseLock(final String sagaId, final Saga sagaInstance) {
if (sagaInstance == null || !CurrentUnitOfWork.isStarted()) {
lock.releaseLock(sagaId);
} else if (CurrentUnitOfWork.isStarted()) {
CurrentUnitOfWork.get()
.registerListener(
new UnitOfWorkListenerAdapter() {
@Override
public void onCleanup(UnitOfWork unitOfWork) {
// a reference to the saga is maintained to prevent it from GC until after the UoW
// commit
lock.releaseLock(sagaInstance.getSagaIdentifier());
}
});
}
}
/**
* 解决 聚合 的事件 并发 竞争
*
* @param aggregate The aggregate containing the potential conflicts
* @param unseenEvents The events that have been concurrently applied
*/
protected void resolveConflicts(T aggregate, AggregateEventStream unseenEvents) {
CurrentUnitOfWork.get()
.registerListener(new ConflictResolvingListener(aggregate, asList(unseenEvents)));
}