/**
* 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);
}
}
/**
* 执行真正的 保存 事件操作
*
* @param aggregate the aggregate to store
*/
@Override
protected void doSaveWithLock(T aggregate) {
AggregateEventStream eventStream = aggregate.getUncommittedEvents();
try {
Iterator<EventStreamDecorator> iterator = eventStreamDecorators.descendingIterator();
while (iterator.hasNext()) {
eventStream =
iterator.next().decorateForAppend(getTypeIdentifier(), aggregate, eventStream);
}
AggregateEventStore.appendEvents(getTypeIdentifier(), eventStream);
} finally {
IOUtils.closeQuietlyIfCloseable(eventStream);
}
}
