cascadeentityjoinwalker.java

hibernate-distribution-3.3.1.GA-dist.zip源码

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2008, Red Hat Middleware LLC 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 Middleware LLC.
 *
 * 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.loader.entity;

import org.hibernate.FetchMode;
import org.hibernate.LockMode;
import org.hibernate.MappingException;
import org.hibernate.engine.CascadeStyle;
import org.hibernate.engine.CascadingAction;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.loader.AbstractEntityJoinWalker;
import org.hibernate.persister.entity.OuterJoinLoadable;
import org.hibernate.type.AssociationType;
import org.hibernate.util.CollectionHelper;

public class CascadeEntityJoinWalker extends AbstractEntityJoinWalker {
	
	private final CascadingAction cascadeAction;

	public CascadeEntityJoinWalker(OuterJoinLoadable persister, CascadingAction action, SessionFactoryImplementor factory) 
	throws MappingException {
		super( persister, factory, CollectionHelper.EMPTY_MAP );
		this.cascadeAction = action;
		StringBuffer whereCondition = whereString( getAlias(), persister.getIdentifierColumnNames(), 1 )
				//include the discriminator and class-level where, but not filters
				.append( persister.filterFragment( getAlias(), CollectionHelper.EMPTY_MAP ) );
	
		initAll( whereCondition.toString(), "", LockMode.READ );
	}

	protected boolean isJoinedFetchEnabled(AssociationType type, FetchMode config, CascadeStyle cascadeStyle) {
		return ( type.isEntityType() || type.isCollectionType() ) &&
				( cascadeStyle==null || cascadeStyle.doCascade(cascadeAction) );
	}

	protected boolean isTooManyCollections() {
		return countCollectionPersisters(associations)>0;
	}

	public String getComment() {
		return "load " + getPersister().getEntityName();
	}
	
}