Diferencia RollbackFailedEvent para hacer rollback

import es.redmic.brokerlib.avro.common.Event;

import es.redmic.brokerlib.avro.common.EventTypes;

import es.redmic.brokerlib.avro.fail.PrepareRollbackEvent;

import es.redmic.brokerlib.avro.fail.RollbackFailedEvent;

import es.redmic.commandslib.exceptions.HistoryNotFoundException;

import es.redmic.commandslib.exceptions.ItemLockedException;

import es.redmic.exception.data.ItemNotFoundException;

import es.redmic.exception.settings.SettingsChangeForbiddenException;

import es.redmic.usersettingslib.events.SettingsEventTypes;

public abstract class Aggregate {

		Event blockedEvent = getItemFromStateStore(id);

		if (!SettingsEventTypes.isSnapshot(blockedEvent.getType())

				&& blockedEventRequiresRollback(blockedEvent, timeoutMS))

		if (blockedEventRequiresRollback(blockedEvent, timeoutMS))

			return getRollbackEvent(blockedEvent);

		return null;

	}

				"Un error en el sistema ha dejado un evento en estado bloqueado. Generando evento rollback para evento bloqueado de tipo "

						+ sourceEvent.getType() + ". ItemId : " + sourceEvent.getAggregateId());

		String failEventType = null;

		if (sourceEvent instanceof RollbackFailedEvent)

			failEventType = ((RollbackFailedEvent) sourceEvent).getFailEventType();

		else

			failEventType = sourceEvent.getType();

		PrepareRollbackEvent event = new PrepareRollbackEvent().buildFrom(sourceEvent);

		event.setFailEventType(sourceEvent.getType());

		event.setFailEventType(failEventType);

		return event;

	}

}