cascadingaction.java

来自「好东西,hibernate-3.2.0,他是一开元的树杖hibernate-3.」· Java 代码 · 共 438 行 · 第 1/2 页

		public Iterator getCascadableChildrenIterator(EventSource session, CollectionType collectionType, Object collection) {
			// saves / updates don't cascade to uninitialized collections
			return getLoadedElementsIterator(session, collectionType, collection);
		}
		public boolean deleteOrphans() {
			// orphans should be deleted during save/update
			return true;
		}
		public boolean performOnLazyProperty() {
			return false;
		}
		public String toString() {
			return "ACTION_SAVE_UPDATE";
		}
	};

	/**
	 * @see org.hibernate.Session#merge(Object)
	 */
	public static final CascadingAction MERGE = new CascadingAction() {
		public void cascade(EventSource session, Object child, String entityName, Object anything, boolean isCascadeDeleteEnabled)
		throws HibernateException {
			if ( log.isTraceEnabled() ) {
				log.trace( "cascading to merge: " + entityName );
			}
			session.merge( entityName, child, (Map) anything );
		}
		public Iterator getCascadableChildrenIterator(EventSource session, CollectionType collectionType, Object collection) {
			// merges don't cascade to uninitialized collections
//			//TODO: perhaps this does need to cascade after all....
			return getLoadedElementsIterator(session, collectionType, collection);
		}
		public boolean deleteOrphans() {
			// orphans should not be deleted during merge??
			return false;
		}
		public String toString() {
			return "ACTION_MERGE";
		}
	};

	/**
	 * @see org.hibernate.classic.Session#saveOrUpdateCopy(Object)
	 */
	public static final CascadingAction SAVE_UPDATE_COPY = new CascadingAction() {
		// for deprecated saveOrUpdateCopy()
		public void cascade(EventSource session, Object child, String entityName, Object anything, boolean isCascadeDeleteEnabled)
		throws HibernateException {
			if ( log.isTraceEnabled() ) {
				log.trace( "cascading to saveOrUpdateCopy: " + entityName );
			}
			session.saveOrUpdateCopy( entityName, child, (Map) anything );
		}
		public Iterator getCascadableChildrenIterator(EventSource session, CollectionType collectionType, Object collection) {
			// saves / updates don't cascade to uninitialized collections
			return getLoadedElementsIterator(session, collectionType, collection);
		}
		public boolean deleteOrphans() {
			// orphans should not be deleted during copy??
			return false;
		}
		public String toString() {
			return "ACTION_SAVE_UPDATE_COPY";
		}
	};

	/**
	 * @see org.hibernate.Session#persist(Object)
	 */
	public static final CascadingAction PERSIST = new CascadingAction() {
		public void cascade(EventSource session, Object child, String entityName, Object anything, boolean isCascadeDeleteEnabled)
		throws HibernateException {
			if ( log.isTraceEnabled() ) {
				log.trace( "cascading to persist: " + entityName );
			}
			session.persist( entityName, child, (Map) anything );
		}
		public Iterator getCascadableChildrenIterator(EventSource session, CollectionType collectionType, Object collection) {
			// persists don't cascade to uninitialized collections
			return CascadingAction.getAllElementsIterator(session, collectionType, collection);
		}
		public boolean deleteOrphans() {
			return false;
		}
		public boolean performOnLazyProperty() {
			return false;
		}
		public String toString() {
			return "ACTION_PERSIST";
		}
	};

	/**
	 * Execute persist during flush time
	 *
	 * @see org.hibernate.Session#persist(Object)
	 */
	public static final CascadingAction PERSIST_ON_FLUSH = new CascadingAction() {
		public void cascade(EventSource session, Object child, String entityName, Object anything, boolean isCascadeDeleteEnabled)
		throws HibernateException {
			if ( log.isTraceEnabled() ) {
				log.trace( "cascading to persistOnFlush: " + entityName );
			}
			session.persistOnFlush( entityName, child, (Map) anything );
		}
		public Iterator getCascadableChildrenIterator(EventSource session, CollectionType collectionType, Object collection) {
			// persists don't cascade to uninitialized collections
			return CascadingAction.getLoadedElementsIterator(session, collectionType, collection);
		}
		public boolean deleteOrphans() {
			return true;
		}
		public boolean requiresNoCascadeChecking() {
			return true;
		}
		public void noCascade(
				EventSource session,
				Object child,
				Object parent,
				EntityPersister persister,
				int propertyIndex) {
			if ( child == null ) {
				return;
			}
			Type type = persister.getPropertyTypes()[propertyIndex];
			if ( type.isEntityType() ) {
				String childEntityName = ( ( EntityType ) type ).getAssociatedEntityName( session.getFactory() );

				if ( ! isInManagedState( child, session )
						&& ! ( child instanceof HibernateProxy ) //a proxy cannot be transient and it breaks ForeignKeys.isTransient
						&& ForeignKeys.isTransient( childEntityName, child, null, session ) ) {
					String parentEntiytName = persister.getEntityName();
					String propertyName = persister.getPropertyNames()[propertyIndex];
					throw new TransientObjectException(
							"object references an unsaved transient instance - " +
							"save the transient instance before flushing: " +
							parentEntiytName + "." + propertyName + " -> " + childEntityName
					);

				}
			}
		}
		public boolean performOnLazyProperty() {
			return false;
		}

		private boolean isInManagedState(Object child, EventSource session) {
			EntityEntry entry = session.getPersistenceContext().getEntry( child );
			return entry != null && (entry.getStatus() == Status.MANAGED || entry.getStatus() == Status.READ_ONLY);
		}

		public String toString() {
			return "ACTION_PERSIST_ON_FLUSH";
		}
	};

	/**
	 * @see org.hibernate.Session#replicate(Object, org.hibernate.ReplicationMode)
	 */
	public static final CascadingAction REPLICATE = new CascadingAction() {
		public void cascade(EventSource session, Object child, String entityName, Object anything, boolean isCascadeDeleteEnabled)
		throws HibernateException {
			if ( log.isTraceEnabled() ) {
				log.trace( "cascading to replicate: " + entityName );
			}
			session.replicate( entityName, child, (ReplicationMode) anything );
		}
		public Iterator getCascadableChildrenIterator(EventSource session, CollectionType collectionType, Object collection) {
			// replicate does cascade to uninitialized collections
			return getLoadedElementsIterator(session, collectionType, collection);
		}
		public boolean deleteOrphans() {
			return false; //I suppose?
		}
		public String toString() {
			return "ACTION_REPLICATE";
		}
	};


	// static helper methods ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	/**
	 * Given a collection, get an iterator of all its children, loading them
	 * from the database if necessary.
	 *
	 * @param session The session within which the cascade is occuring.
	 * @param collectionType The mapping type of the collection.
	 * @param collection The collection instance.
	 * @return The children iterator.
	 */
	private static Iterator getAllElementsIterator(
			EventSource session,
			CollectionType collectionType,
			Object collection) {
		return collectionType.getElementsIterator( collection, session );
	}

	/**
	 * Iterate just the elements of the collection that are already there. Don't load
	 * any new elements from the database.
	 */
	public static Iterator getLoadedElementsIterator(SessionImplementor session, CollectionType collectionType, Object collection) {
		if ( collectionIsInitialized(collection) ) {
			// handles arrays and newly instantiated collections
			return collectionType.getElementsIterator(collection, session);
		}
		else {
			// does not handle arrays (thats ok, cos they can't be lazy)
			// or newly instantiated collections, so we can do the cast
			return ( (PersistentCollection) collection ).queuedAdditionIterator();
		}
	}

	private static boolean collectionIsInitialized(Object collection) {
		return !(collection instanceof PersistentCollection) || ( (PersistentCollection) collection ).wasInitialized();
	}

}