//$Id: CollectionRemoveAction.java 7147 2005-06-15 13:20:13Z oneovthafew $
package org.hibernate.action;
import org.hibernate.HibernateException;
import org.hibernate.AssertionFailure;
import org.hibernate.event.PostCollectionRemoveEvent;
import org.hibernate.event.PreCollectionRemoveEvent;
import org.hibernate.event.PreCollectionRemoveEventListener;
import org.hibernate.event.EventSource;
import org.hibernate.event.PostCollectionRemoveEventListener;
import org.hibernate.cache.CacheException;
import org.hibernate.collection.PersistentCollection;
import org.hibernate.engine.SessionImplementor;
import org.hibernate.persister.collection.CollectionPersister;
import java.io.Serializable;
public final class CollectionRemoveAction extends CollectionAction {
private boolean emptySnapshot;
private final Object affectedOwner;
/**
* Removes a persistent collection from its loaded owner.
*
* Use this constructor when the collection is non-null.
*
* @param collection The collection to to remove; must be non-null
* @param persister The collection's persister
* @param id The collection key
* @param emptySnapshot Indicates if the snapshot is empty
* @param session The session
* @throws AssertionFailure if collection is null.
*/
public CollectionRemoveAction(
final PersistentCollection collection,
final CollectionPersister persister,
final Serializable id,
final boolean emptySnapshot,
final SessionImplementor session)
throws CacheException {
super( persister, collection, id, session );
if (collection == null) { throw new AssertionFailure("collection == null"); }
this.emptySnapshot = emptySnapshot;
// the loaded owner will be set to null after the collection is removed,
// so capture its value as the affected owner so it is accessible to
// both pre- and post- events
this.affectedOwner = session.getPersistenceContext().getLoadedCollectionOwnerOrNull( collection );
}
/**
* Removes a persistent collection from a specified owner.
*
* Use this constructor when the collection to be removed has not been loaded.
*
* @param affectedOwner The collection's owner; must be non-null
* @param persister The collection's persister
* @param id The collection key
* @param emptySnapshot Indicates if the snapshot is empty
* @param session The session
* @throws AssertionFailure if affectedOwner is null.
*/
public CollectionRemoveAction(
final Object affectedOwner,
final CollectionPersister persister,
final Serializable id,
final boolean emptySnapshot,
final SessionImplementor session)
throws CacheException {
super( persister, null, id, session );
if (affectedOwner == null) { throw new AssertionFailure("affectedOwner == null"); }
this.emptySnapshot = emptySnapshot;
this.affectedOwner = affectedOwner;
}
public void execute() throws HibernateException {
preRemove();
if ( !emptySnapshot ) {
// an existing collection that was either non-empty or uninitialized
// is replaced by null or a different collection
// (if the collection is uninitialized, hibernate has no way of
// knowing if the collection is actually empty without querying the db)
getPersister().remove( getKey(), getSession() );
}
final PersistentCollection collection = getCollection();
if (collection!=null) {
getSession().getPersistenceContext()
.getCollectionEntry(collection)
.afterAction(collection);
}
evict();
postRemove();
if ( getSession().getFactory().getStatistics().isStatisticsEnabled() ) {
getSession().getFactory().getStatisticsImplementor()
.removeCollection( getPersister().getRole() );
}
}
private void preRemove() {
PreCollectionRemoveEventListener[] preListeners = getSession().getListeners()
.getPreCollectionRemoveEventListeners();
if (preListeners.length>0) {
PreCollectionRemoveEvent preEvent = new PreCollectionRemoveEvent(
getPersister(), getCollection(), ( EventSource ) getSession(), affectedOwner );
for ( int i = 0; i < preListeners.length; i++ ) {
preListeners[i].onPreRemoveCollection(preEvent);
}
}
}
private void postRemove() {
PostCollectionRemoveEventListener[] postListeners = getSession().getListeners()
.getPostCollectionRemoveEventListeners();
if (postListeners.length>0) {
PostCollectionRemoveEvent postEvent = new PostCollectionRemoveEvent(
getPersister(), getCollection(), ( EventSource ) getSession(), affectedOwner );
for ( int i = 0; i < postListeners.length; i++ ) {
postListeners[i].onPostRemoveCollection(postEvent);
}
}
}
}