/**
* Handle the given lock event.
*
* @param event The lock event to be handled.
* @throws HibernateException
*/
public void onLock(LockEvent event) throws HibernateException {
if (event.getObject() == null) {
throw new NullPointerException("attempted to lock null");
}
if (event.getLockMode() == LockMode.WRITE) {
throw new HibernateException("Invalid lock mode for lock()");
}
SessionImplementor source = event.getSession();
Object entity = source.getPersistenceContext().unproxyAndReassociate(event.getObject());
// TODO: if object was an uninitialized proxy, this is inefficient,
// resulting in two SQL selects
EntityEntry entry = source.getPersistenceContext().getEntry(entity);
if (entry == null) {
final EntityPersister persister = source.getEntityPersister(event.getEntityName(), entity);
final Serializable id = persister.getIdentifier(entity, source.getEntityMode());
if (!ForeignKeys.isNotTransient(event.getEntityName(), entity, Boolean.FALSE, source)) {
throw new TransientObjectException(
"cannot lock an unsaved transient instance: " + persister.getEntityName());
}
entry = reassociate(event, entity, id, persister);
cascadeOnLock(event, persister, entity);
}
upgradeLock(entity, entry, event.getLockMode(), source);
}
private void cascadeOnLock(LockEvent event, EntityPersister persister, Object entity) {
EventSource source = event.getSession();
source.getPersistenceContext().incrementCascadeLevel();
try {
new Cascade(CascadingAction.LOCK, Cascade.AFTER_LOCK, source)
.cascade(persister, entity, event.getLockMode());
} finally {
source.getPersistenceContext().decrementCascadeLevel();
}
}