/*
 * 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
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package org.hibernate.loader.entity;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;

import org.hibernate.FetchMode;
import org.hibernate.LockMode;
import org.hibernate.LockOptions;
import org.hibernate.MappingException;
import org.hibernate.engine.spi.CascadeStyle;
import org.hibernate.engine.spi.LoadQueryInfluencers;
import org.hibernate.engine.spi.SessionFactoryImplementor;
import org.hibernate.loader.AbstractEntityJoinWalker;
import org.hibernate.loader.OuterJoinableAssociation;
import org.hibernate.loader.PropertyPath;
import org.hibernate.persister.collection.QueryableCollection;
import org.hibernate.persister.entity.EntityPersister;
import org.hibernate.persister.entity.OuterJoinLoadable;
import org.hibernate.sql.JoinType;
import org.hibernate.type.AssociationType;
import org.hibernate.type.CompositeType;
import org.hibernate.type.EntityType;
import org.hibernate.type.Type;

A walker for loaders that fetch entities
Author:Gavin King
See Also:
  • EntityLoader
/** * A walker for loaders that fetch entities * * @see EntityLoader * @author Gavin King */
public class EntityJoinWalker extends AbstractEntityJoinWalker { private final LockOptions lockOptions = new LockOptions(); private final int[][] compositeKeyManyToOneTargetIndices; public EntityJoinWalker( OuterJoinLoadable persister, String[] uniqueKey, int batchSize, LockMode lockMode, final SessionFactoryImplementor factory, LoadQueryInfluencers loadQueryInfluencers) throws MappingException { super( persister, factory, loadQueryInfluencers ); this.lockOptions.setLockMode(lockMode); StringBuilder whereCondition = whereString( getAlias(), uniqueKey, batchSize ) //include the discriminator and class-level where, but not filters .append( persister.filterFragment( getAlias(), Collections.EMPTY_MAP ) ); AssociationInitCallbackImpl callback = new AssociationInitCallbackImpl( factory ); initAll( whereCondition.toString(), "", lockOptions, callback ); this.compositeKeyManyToOneTargetIndices = callback.resolve(); } public EntityJoinWalker( OuterJoinLoadable persister, String[] uniqueKey, int batchSize, LockOptions lockOptions, SessionFactoryImplementor factory, LoadQueryInfluencers loadQueryInfluencers) throws MappingException { super( persister, factory, loadQueryInfluencers ); LockOptions.copy(lockOptions, this.lockOptions); StringBuilder whereCondition = whereString( getAlias(), uniqueKey, batchSize ) //include the discriminator and class-level where, but not filters .append( persister.filterFragment( getAlias(), Collections.EMPTY_MAP ) ); AssociationInitCallbackImpl callback = new AssociationInitCallbackImpl( factory ); initAll( whereCondition.toString(), "", lockOptions, callback ); this.compositeKeyManyToOneTargetIndices = callback.resolve(); } protected JoinType getJoinType( OuterJoinLoadable persister, PropertyPath path, int propertyNumber, AssociationType associationType, FetchMode metadataFetchMode, CascadeStyle metadataCascadeStyle, String lhsTable, String[] lhsColumns, boolean nullable, int currentDepth) throws MappingException { // NOTE : we override this form here specifically to account for // fetch profiles. // TODO : how to best handle criteria queries? if ( lockOptions.getLockMode().greaterThan( LockMode.READ ) ) { return JoinType.NONE; } if ( isTooDeep( currentDepth ) || ( associationType.isCollectionType() && isTooManyCollections() ) ) { return JoinType.NONE; } if ( !isJoinedFetchEnabledInMapping( metadataFetchMode, associationType ) && !isJoinFetchEnabledByProfile( persister, path, propertyNumber ) ) { return JoinType.NONE; } if ( isDuplicateAssociation( lhsTable, lhsColumns, associationType ) ) { return JoinType.NONE; } return getJoinType( nullable, currentDepth ); } public String getComment() { return "load " + getPersister().getEntityName(); } public int[][] getCompositeKeyManyToOneTargetIndices() { return compositeKeyManyToOneTargetIndices; } private static class AssociationInitCallbackImpl implements AssociationInitCallback { private final SessionFactoryImplementor factory; private final HashMap<String,OuterJoinableAssociation> associationsByAlias = new HashMap<String, OuterJoinableAssociation>(); private final HashMap<String,Integer> positionsByAlias = new HashMap<String, Integer>(); private final ArrayList<String> aliasesForAssociationsWithCompositesIds = new ArrayList<String>(); public AssociationInitCallbackImpl(SessionFactoryImplementor factory) { this.factory = factory; } public void associationProcessed(OuterJoinableAssociation oja, int position) { associationsByAlias.put( oja.getRhsAlias(), oja ); positionsByAlias.put( oja.getRhsAlias(), position ); EntityPersister entityPersister = null; if ( oja.getJoinableType().isCollectionType() ) { entityPersister = ( ( QueryableCollection) oja.getJoinable() ).getElementPersister(); } else if ( oja.getJoinableType().isEntityType() ) { entityPersister = ( EntityPersister ) oja.getJoinable(); } if ( entityPersister != null && entityPersister.getIdentifierType().isComponentType() && ! entityPersister.getEntityMetamodel().getIdentifierProperty().isEmbedded() && hasAssociation( (CompositeType) entityPersister.getIdentifierType() ) ) { aliasesForAssociationsWithCompositesIds.add( oja.getRhsAlias() ); } } private boolean hasAssociation(CompositeType componentType) { for ( Type subType : componentType.getSubtypes() ) { if ( subType.isEntityType() ) { return true; } else if ( subType.isComponentType() && hasAssociation( ( (CompositeType) subType ) ) ) { return true; } } return false; } public int[][] resolve() { int[][] compositeKeyManyToOneTargetIndices = null; for ( final String aliasWithCompositeId : aliasesForAssociationsWithCompositesIds ) { final OuterJoinableAssociation joinWithCompositeId = associationsByAlias.get( aliasWithCompositeId ); final ArrayList<Integer> keyManyToOneTargetIndices = new ArrayList<Integer>(); // for each association with a composite id containing key-many-to-one(s), find the bidirectional side of // each key-many-to-one (if exists) to see if it is eager as well. If so, we need to track the indices EntityPersister entityPersister = null; if ( joinWithCompositeId.getJoinableType().isCollectionType() ) { entityPersister = ( ( QueryableCollection) joinWithCompositeId.getJoinable() ).getElementPersister(); } else if ( joinWithCompositeId.getJoinableType().isEntityType() ) { entityPersister = ( EntityPersister ) joinWithCompositeId.getJoinable(); } findKeyManyToOneTargetIndices( keyManyToOneTargetIndices, joinWithCompositeId, (CompositeType) entityPersister.getIdentifierType() ); if ( ! keyManyToOneTargetIndices.isEmpty() ) { if ( compositeKeyManyToOneTargetIndices == null ) { compositeKeyManyToOneTargetIndices = new int[ associationsByAlias.size() ][]; } int position = positionsByAlias.get( aliasWithCompositeId ); compositeKeyManyToOneTargetIndices[position] = new int[ keyManyToOneTargetIndices.size() ]; int i = 0; for ( int index : keyManyToOneTargetIndices ) { compositeKeyManyToOneTargetIndices[position][i] = index; i++; } } } return compositeKeyManyToOneTargetIndices; } private void findKeyManyToOneTargetIndices( ArrayList<Integer> keyManyToOneTargetIndices, OuterJoinableAssociation joinWithCompositeId, CompositeType componentType) { for ( Type subType : componentType.getSubtypes() ) { if ( subType.isEntityType() ) { Integer index = locateKeyManyToOneTargetIndex( joinWithCompositeId, (EntityType) subType ); if ( index != null ) { keyManyToOneTargetIndices.add( index ); } } else if ( subType.isComponentType() ) { findKeyManyToOneTargetIndices( keyManyToOneTargetIndices, joinWithCompositeId, (CompositeType) subType ); } } } private Integer locateKeyManyToOneTargetIndex(OuterJoinableAssociation joinWithCompositeId, EntityType keyManyToOneType) { // the lhs (if one) is a likely candidate if ( joinWithCompositeId.getLhsAlias() != null ) { final OuterJoinableAssociation lhs = associationsByAlias.get( joinWithCompositeId.getLhsAlias() ); if ( keyManyToOneType.getAssociatedEntityName( factory ).equals( lhs.getJoinableType().getAssociatedEntityName( factory ) ) ) { return positionsByAlias.get( lhs.getRhsAlias() ); } } // otherwise, seek out OuterJoinableAssociation which are RHS of given OuterJoinableAssociation // (joinWithCompositeId) for ( OuterJoinableAssociation oja : associationsByAlias.values() ) { if ( oja.getLhsAlias() != null && oja.getLhsAlias().equals( joinWithCompositeId.getRhsAlias() ) ) { if ( keyManyToOneType.equals( oja.getJoinableType() ) ) { return positionsByAlias.get( oja.getLhsAlias() ); } } } return null; } } }