/* * Hibernate, Relational Persistence for Idiomatic Java * * Copyright (c) 2010, Red Hat Inc. or third-party contributors as * indicated by the @author tags or express copyright attribution * statements applied by the authors. All third-party contributions are * distributed under license by Red Hat Inc. * * This copyrighted material is made available to anyone wishing to use, modify, * copy, or redistribute it subject to the terms and conditions of the GNU * Lesser General Public License, as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License * for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this distribution; if not, write to: * Free Software Foundation, Inc. * 51 Franklin Street, Fifth Floor * Boston, MA 02110-1301 USA */ package org.hibernate.type; import java.io.Serializable; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.Collection; import java.util.Iterator; import java.util.List; import java.util.Map; import org.dom4j.Element; import org.dom4j.Node; import org.hibernate.EntityMode; import org.hibernate.Hibernate; import org.hibernate.HibernateException; import org.hibernate.MappingException; import org.hibernate.collection.spi.PersistentCollection; import org.hibernate.engine.spi.CollectionKey; import org.hibernate.engine.spi.EntityEntry; import org.hibernate.engine.spi.Mapping; import org.hibernate.engine.spi.PersistenceContext; import org.hibernate.engine.spi.SessionFactoryImplementor; import org.hibernate.engine.spi.SessionImplementor; import org.hibernate.internal.util.MarkerObject; import org.hibernate.internal.util.collections.ArrayHelper; import org.hibernate.metamodel.relational.Size; import org.hibernate.persister.collection.CollectionPersister; import org.hibernate.persister.collection.QueryableCollection; import org.hibernate.persister.entity.EntityPersister; import org.hibernate.persister.entity.Joinable; import org.hibernate.proxy.HibernateProxy; import org.hibernate.proxy.LazyInitializer; /** * A type that handles Hibernate <tt>PersistentCollection</tt>s (including arrays). * * @author Gavin King */ public abstract class CollectionType extends AbstractType implements AssociationType { private static final Object NOT_NULL_COLLECTION = new MarkerObject( "NOT NULL COLLECTION" ); public static final Object UNFETCHED_COLLECTION = new MarkerObject( "UNFETCHED COLLECTION" ); private final TypeFactory.TypeScope typeScope; private final String role; private final String foreignKeyPropertyName; private final boolean isEmbeddedInXML; public CollectionType(TypeFactory.TypeScope typeScope, String role, String foreignKeyPropertyName, boolean isEmbeddedInXML) { this.typeScope = typeScope; this.role = role; this.foreignKeyPropertyName = foreignKeyPropertyName; this.isEmbeddedInXML = isEmbeddedInXML; } public boolean isEmbeddedInXML() { return isEmbeddedInXML; } public String getRole() { return role; } public Object indexOf(Object collection, Object element) { throw new UnsupportedOperationException( "generic collections don't have indexes" ); } public boolean contains(Object collection, Object childObject, SessionImplementor session) { // we do not have to worry about queued additions to uninitialized // collections, since they can only occur for inverse collections! Iterator elems = getElementsIterator( collection, session ); while ( elems.hasNext() ) { Object element = elems.next(); // worrying about proxies is perhaps a little bit of overkill here... if ( element instanceof HibernateProxy ) { LazyInitializer li = ( (HibernateProxy) element ).getHibernateLazyInitializer(); if ( !li.isUninitialized() ) element = li.getImplementation(); } if ( element == childObject ) return true; } return false; } public boolean isCollectionType() { return true; } public final boolean isEqual(Object x, Object y) { return x == y || ( x instanceof PersistentCollection && ( (PersistentCollection) x ).isWrapper( y ) ) || ( y instanceof PersistentCollection && ( (PersistentCollection) y ).isWrapper( x ) ); } public int compare(Object x, Object y) { return 0; // collections cannot be compared } public int getHashCode(Object x) { throw new UnsupportedOperationException( "cannot doAfterTransactionCompletion lookups on collections" ); } /** * Instantiate an uninitialized collection wrapper or holder. Callers MUST add the holder to the * persistence context! * * @param session The session from which the request is originating. * @param persister The underlying collection persister (metadata) * @param key The owner key. * @return The instantiated collection. */ public abstract PersistentCollection instantiate(SessionImplementor session, CollectionPersister persister, Serializable key); public Object nullSafeGet(ResultSet rs, String name, SessionImplementor session, Object owner) throws SQLException { return nullSafeGet( rs, new String[] { name }, session, owner ); } public Object nullSafeGet(ResultSet rs, String[] name, SessionImplementor session, Object owner) throws HibernateException, SQLException { return resolve( null, session, owner ); } public final void nullSafeSet(PreparedStatement st, Object value, int index, boolean[] settable, SessionImplementor session) throws HibernateException, SQLException { //NOOP } public void nullSafeSet(PreparedStatement st, Object value, int index, SessionImplementor session) throws HibernateException, SQLException { } public int[] sqlTypes(Mapping session) throws MappingException { return ArrayHelper.EMPTY_INT_ARRAY; } @Override public Size[] dictatedSizes(Mapping mapping) throws MappingException { return new Size[] { LEGACY_DICTATED_SIZE }; } @Override public Size[] defaultSizes(Mapping mapping) throws MappingException { return new Size[] { LEGACY_DEFAULT_SIZE }; } public int getColumnSpan(Mapping session) throws MappingException { return 0; } public String toLoggableString(Object value, SessionFactoryImplementor factory) throws HibernateException { if ( value == null ) { return "null"; } else if ( !Hibernate.isInitialized( value ) ) { return "<uninitialized>"; } else { return renderLoggableString( value, factory ); } } protected String renderLoggableString(Object value, SessionFactoryImplementor factory) throws HibernateException { final List<String> list = new ArrayList<String>(); Type elemType = getElementType( factory ); Iterator itr = getElementsIterator( value ); while ( itr.hasNext() ) { list.add( elemType.toLoggableString( itr.next(), factory ) ); } return list.toString(); } public Object deepCopy(Object value, SessionFactoryImplementor factory) throws HibernateException { return value; } public String getName() { return getReturnedClass().getName() + '(' + getRole() + ')'; } /** * Get an iterator over the element set of the collection, which may not yet be wrapped * * @param collection The collection to be iterated * @param session The session from which the request is originating. * @return The iterator. */ public Iterator getElementsIterator(Object collection, SessionImplementor session) { return getElementsIterator(collection); } /** * Get an iterator over the element set of the collection in POJO mode * * @param collection The collection to be iterated * @return The iterator. */ protected Iterator getElementsIterator(Object collection) { return ( (Collection) collection ).iterator(); } public boolean isMutable() { return false; } public Serializable disassemble(Object value, SessionImplementor session, Object owner) throws HibernateException { //remember the uk value //This solution would allow us to eliminate the owner arg to disassemble(), but //what if the collection was null, and then later had elements added? seems unsafe //session.getPersistenceContext().getCollectionEntry( (PersistentCollection) value ).getKey(); final Serializable key = getKeyOfOwner(owner, session); if (key==null) { return null; } else { return getPersister(session) .getKeyType() .disassemble( key, session, owner ); } } public Object assemble(Serializable cached, SessionImplementor session, Object owner) throws HibernateException { //we must use the "remembered" uk value, since it is //not available from the EntityEntry during assembly if (cached==null) { return null; } else { final Serializable key = (Serializable) getPersister(session) .getKeyType() .assemble( cached, session, owner); return resolveKey( key, session, owner ); } } /** * Is the owning entity versioned? * * @param session The session from which the request is originating. * @return True if the collection owner is versioned; false otherwise. * @throws org.hibernate.MappingException Indicates our persister could not be located. */ private boolean isOwnerVersioned(SessionImplementor session) throws MappingException { return getPersister( session ).getOwnerEntityPersister().isVersioned(); } /** * Get our underlying collection persister (using the session to access the * factory). * * @param session The session from which the request is originating. * @return The underlying collection persister */ private CollectionPersister getPersister(SessionImplementor session) { return session.getFactory().getCollectionPersister( role ); } public boolean isDirty(Object old, Object current, SessionImplementor session) throws HibernateException { // collections don't dirty an unversioned parent entity // TODO: I don't really like this implementation; it would be better if // this was handled by searchForDirtyCollections() return isOwnerVersioned( session ) && super.isDirty( old, current, session ); // return false; } public boolean isDirty(Object old, Object current, boolean[] checkable, SessionImplementor session) throws HibernateException { return isDirty(old, current, session); } /** * Wrap the naked collection instance in a wrapper, or instantiate a * holder. Callers <b>MUST</b> add the holder to the persistence context! * * @param session The session from which the request is originating. * @param collection The bare collection to be wrapped. * @return The wrapped collection. */ public abstract PersistentCollection wrap(SessionImplementor session, Object collection); /** * Note: return true because this type is castable to <tt>AssociationType</tt>. Not because * all collections are associations. */ public boolean isAssociationType() { return true; } public ForeignKeyDirection getForeignKeyDirection() { return ForeignKeyDirection.FOREIGN_KEY_TO_PARENT; } /** * Get the key value from the owning entity instance, usually the identifier, but might be some * other unique key, in the case of property-ref * * @param owner The collection owner * @param session The session from which the request is originating. * @return The collection owner's key */ public Serializable getKeyOfOwner(Object owner, SessionImplementor session) { EntityEntry entityEntry = session.getPersistenceContext().getEntry( owner ); if ( entityEntry == null ) return null; // This just handles a particular case of component // projection, perhaps get rid of it and throw an exception if ( foreignKeyPropertyName == null ) { return entityEntry.getId(); } else { // TODO: at the point where we are resolving collection references, we don't // know if the uk value has been resolved (depends if it was earlier or // later in the mapping document) - now, we could try and use e.getStatus() // to decide to semiResolve(), trouble is that initializeEntity() reuses // the same array for resolved and hydrated values Object id; if ( entityEntry.getLoadedState() != null ) { id = entityEntry.getLoadedValue( foreignKeyPropertyName ); } else { id = entityEntry.getPersister().getPropertyValue( owner, foreignKeyPropertyName ); } // NOTE VERY HACKISH WORKAROUND!! // TODO: Fix this so it will work for non-POJO entity mode Type keyType = getPersister( session ).getKeyType(); if ( !keyType.getReturnedClass().isInstance( id ) ) { id = (Serializable) keyType.semiResolve( entityEntry.getLoadedValue( foreignKeyPropertyName ), session, owner ); } return (Serializable) id; } } /** * Get the id value from the owning entity key, usually the same as the key, but might be some * other property, in the case of property-ref * * @param key The collection owner key * @param session The session from which the request is originating. * @return The collection owner's id, if it can be obtained from the key; * otherwise, null is returned */ public Serializable getIdOfOwnerOrNull(Serializable key, SessionImplementor session) { Serializable ownerId = null; if ( foreignKeyPropertyName == null ) { ownerId = key; } else { Type keyType = getPersister( session ).getKeyType(); EntityPersister ownerPersister = getPersister( session ).getOwnerEntityPersister(); // TODO: Fix this so it will work for non-POJO entity mode Class ownerMappedClass = ownerPersister.getMappedClass(); if ( ownerMappedClass.isAssignableFrom( keyType.getReturnedClass() ) && keyType.getReturnedClass().isInstance( key ) ) { // the key is the owning entity itself, so get the ID from the key ownerId = ownerPersister.getIdentifier( key, session ); } else { // TODO: check if key contains the owner ID } } return ownerId; } public Object hydrate(ResultSet rs, String[] name, SessionImplementor session, Object owner) { // can't just return null here, since that would // cause an owning component to become null return NOT_NULL_COLLECTION; } public Object resolve(Object value, SessionImplementor session, Object owner) throws HibernateException { return resolveKey( getKeyOfOwner( owner, session ), session, owner ); } private Object resolveKey(Serializable key, SessionImplementor session, Object owner) { // if (key==null) throw new AssertionFailure("owner identifier unknown when re-assembling // collection reference"); return key == null ? null : // TODO: can this case really occur?? getCollection( key, session, owner ); } public Object semiResolve(Object value, SessionImplementor session, Object owner) throws HibernateException { throw new UnsupportedOperationException( "collection mappings may not form part of a property-ref" ); } public boolean isArrayType() { return false; } public boolean useLHSPrimaryKey() { return foreignKeyPropertyName == null; } public String getRHSUniqueKeyPropertyName() { return null; } public Joinable getAssociatedJoinable(SessionFactoryImplementor factory) throws MappingException { return (Joinable) factory.getCollectionPersister( role ); } public boolean isModified(Object old, Object current, boolean[] checkable, SessionImplementor session) throws HibernateException { return false; } public String getAssociatedEntityName(SessionFactoryImplementor factory) throws MappingException { try { QueryableCollection collectionPersister = (QueryableCollection) factory .getCollectionPersister( role ); if ( !collectionPersister.getElementType().isEntityType() ) { throw new MappingException( "collection was not an association: " + collectionPersister.getRole() ); } return collectionPersister.getElementPersister().getEntityName(); } catch (ClassCastException cce) { throw new MappingException( "collection role is not queryable " + role ); } } /** * Replace the elements of a collection with the elements of another collection. * * @param original The 'source' of the replacement elements (where we copy from) * @param target The target of the replacement elements (where we copy to) * @param owner The owner of the collection being merged * @param copyCache The map of elements already replaced. * @param session The session from which the merge event originated. * @return The merged collection. */ public Object replaceElements( Object original, Object target, Object owner, Map copyCache, SessionImplementor session) { // TODO: does not work for EntityMode.DOM4J yet! java.util.Collection result = ( java.util.Collection ) target; result.clear(); // copy elements into newly empty target collection Type elemType = getElementType( session.getFactory() ); Iterator iter = ( (java.util.Collection) original ).iterator(); while ( iter.hasNext() ) { result.add( elemType.replace( iter.next(), null, session, owner, copyCache ) ); } // if the original is a PersistentCollection, and that original // was not flagged as dirty, then reset the target's dirty flag // here after the copy operation. // </p> // One thing to be careful of here is a "bare" original collection // in which case we should never ever ever reset the dirty flag // on the target because we simply do not know... if ( original instanceof PersistentCollection ) { if ( result instanceof PersistentCollection ) { if ( ! ( ( PersistentCollection ) original ).isDirty() ) { ( ( PersistentCollection ) result ).clearDirty(); } } } return result; } /** * Instantiate a new "underlying" collection exhibiting the same capacity * charactersitcs and the passed "original". * * @param original The original collection. * @return The newly instantiated collection. */ protected Object instantiateResult(Object original) { // by default just use an unanticipated capacity since we don't // know how to extract the capacity to use from original here... return instantiate( -1 ); } /** * Instantiate an empty instance of the "underlying" collection (not a wrapper), * but with the given anticipated size (i.e. accounting for initial capacity * and perhaps load factor). * * @param anticipatedSize The anticipated size of the instaniated collection * after we are done populating it. * @return A newly instantiated collection to be wrapped. */ public abstract Object instantiate(int anticipatedSize); /** * {@inheritDoc} */ public Object replace( final Object original, final Object target, final SessionImplementor session, final Object owner, final Map copyCache) throws HibernateException { if ( original == null ) { return null; } if ( !Hibernate.isInitialized( original ) ) { return target; } // for a null target, or a target which is the same as the original, we // need to put the merged elements in a new collection Object result = target == null || target == original ? instantiateResult( original ) : target; //for arrays, replaceElements() may return a different reference, since //the array length might not match result = replaceElements( original, result, owner, copyCache, session ); if ( original == target ) { // get the elements back into the target making sure to handle dirty flag boolean wasClean = PersistentCollection.class.isInstance( target ) && !( ( PersistentCollection ) target ).isDirty(); //TODO: this is a little inefficient, don't need to do a whole // deep replaceElements() call replaceElements( result, target, owner, copyCache, session ); if ( wasClean ) { ( ( PersistentCollection ) target ).clearDirty(); } result = target; } return result; } /** * Get the Hibernate type of the collection elements * * @param factory The session factory. * @return The type of the collection elements * @throws MappingException Indicates the underlying persister could not be located. */ public final Type getElementType(SessionFactoryImplementor factory) throws MappingException { return factory.getCollectionPersister( getRole() ).getElementType(); } public String toString() { return getClass().getName() + '(' + getRole() + ')'; } public String getOnCondition(String alias, SessionFactoryImplementor factory, Map enabledFilters) throws MappingException { return getAssociatedJoinable( factory ).filterFragment( alias, enabledFilters ); } /** * instantiate a collection wrapper (called when loading an object) * * @param key The collection owner key * @param session The session from which the request is originating. * @param owner The collection owner * @return The collection */ public Object getCollection(Serializable key, SessionImplementor session, Object owner) { CollectionPersister persister = getPersister( session ); final PersistenceContext persistenceContext = session.getPersistenceContext(); final EntityMode entityMode = persister.getOwnerEntityPersister().getEntityMode(); // check if collection is currently being loaded PersistentCollection collection = persistenceContext.getLoadContexts().locateLoadingCollection( persister, key ); if ( collection == null ) { // check if it is already completely loaded, but unowned collection = persistenceContext.useUnownedCollection( new CollectionKey(persister, key, entityMode) ); if ( collection == null ) { // create a new collection wrapper, to be initialized later collection = instantiate( session, persister, key ); collection.setOwner(owner); persistenceContext.addUninitializedCollection( persister, collection, key ); // some collections are not lazy: if ( initializeImmediately() ) { session.initializeCollection( collection, false ); } else if ( !persister.isLazy() ) { persistenceContext.addNonLazyCollection( collection ); } if ( hasHolder() ) { session.getPersistenceContext().addCollectionHolder( collection ); } } } collection.setOwner(owner); return collection.getValue(); } public boolean hasHolder() { return false; } protected boolean initializeImmediately() { return false; } public String getLHSPropertyName() { return foreignKeyPropertyName; } public boolean isXMLElement() { return true; } public Object fromXMLNode(Node xml, Mapping factory) throws HibernateException { return xml; } public void setToXMLNode(Node node, Object value, SessionFactoryImplementor factory) throws HibernateException { if ( !isEmbeddedInXML ) { node.detach(); } else { replaceNode( node, (Element) value ); } } /** * We always need to dirty check the collection because we sometimes * need to incremement version number of owner and also because of * how assemble/disassemble is implemented for uks */ public boolean isAlwaysDirtyChecked() { return true; } public boolean[] toColumnNullness(Object value, Mapping mapping) { return ArrayHelper.EMPTY_BOOLEAN_ARRAY; } }