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Hibernate example source code file (HierarchyBuilder.java)

This example Hibernate source code file (HierarchyBuilder.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Hibernate tags/keywords

arraylist, entityhierarchyimpl, extendsqueueentry, extendsqueueentry, list, object, rootentitysourceimpl, string, string, subclassentitycontainer, subclassentitycontainer, subclassentitysourceimpl, subclassentitysourceimpl, subentityelement, util

The Hibernate HierarchyBuilder.java source code

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2011, 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.metamodel.source.hbm;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.hibernate.MappingException;
import org.hibernate.metamodel.source.binder.SubclassEntityContainer;
import org.hibernate.metamodel.source.binder.SubclassEntitySource;
import org.hibernate.metamodel.source.hbm.jaxb.mapping.EntityElement;
import org.hibernate.metamodel.source.hbm.jaxb.mapping.SubEntityElement;
import org.hibernate.metamodel.source.hbm.jaxb.mapping.XMLHibernateMapping;
import org.hibernate.metamodel.source.hbm.jaxb.mapping.XMLJoinedSubclassElement;
import org.hibernate.metamodel.source.hbm.jaxb.mapping.XMLSubclassElement;
import org.hibernate.metamodel.source.hbm.jaxb.mapping.XMLUnionSubclassElement;

/**
 * @author Steve Ebersole
 */
public class HierarchyBuilder {
	private final List<EntityHierarchyImpl> entityHierarchies = new ArrayList();

	// process state
	private final Map<String,SubclassEntityContainer> subEntityContainerMap = new HashMap();
	private final List<ExtendsQueueEntry> extendsQueue = new ArrayList();

	// mapping file specific state
	private MappingDocument currentMappingDocument;

	public void processMappingDocument(MappingDocument mappingDocument) {
		this.currentMappingDocument = mappingDocument;
		try {
			processCurrentMappingDocument();
		}
		finally {
			this.currentMappingDocument = null;
		}
	}

	private void processCurrentMappingDocument() {
		for ( Object entityElementO : currentMappingDocument.getMappingRoot().getClazzOrSubclassOrJoinedSubclass() ) {
			final EntityElement entityElement = (EntityElement) entityElementO;
			if ( XMLHibernateMapping.XMLClass.class.isInstance( entityElement ) ) {
				// we can immediately handle <class/> elements in terms of creating the hierarchy entry
				final XMLHibernateMapping.XMLClass xmlClass = (XMLHibernateMapping.XMLClass) entityElement;
				final RootEntitySourceImpl rootEntitySource = new RootEntitySourceImpl( currentMappingDocument, xmlClass );
				final EntityHierarchyImpl hierarchy = new EntityHierarchyImpl( rootEntitySource );

				entityHierarchies.add( hierarchy );
				subEntityContainerMap.put( rootEntitySource.getEntityName(), rootEntitySource );

				processSubElements( entityElement, rootEntitySource );
			}
			else {
				// we have to see if this things super-type has been found yet, and if not add it to the
				// extends queue
				final SubclassEntitySourceImpl subClassEntitySource = new SubclassEntitySourceImpl( currentMappingDocument, entityElement );
				final String entityName = subClassEntitySource.getEntityName();
				subEntityContainerMap.put( entityName, subClassEntitySource );
				final String entityItExtends = currentMappingDocument.getMappingLocalBindingContext().qualifyClassName(
						((SubEntityElement) entityElement).getExtends()
				);
				processSubElements( entityElement, subClassEntitySource );
				final SubclassEntityContainer container = subEntityContainerMap.get( entityItExtends );
				if ( container != null ) {
					// we already have this entity's super, attach it and continue
					container.add( subClassEntitySource );
				}
				else {
					// we do not yet have the super and have to wait, so add it fto the extends queue
					extendsQueue.add( new ExtendsQueueEntry( subClassEntitySource, entityItExtends ) );
				}
			}
		}
	}

	public List<EntityHierarchyImpl> groupEntityHierarchies() {
		while ( ! extendsQueue.isEmpty() ) {
			// set up a pass over the queue
			int numberOfMappingsProcessed = 0;
			Iterator<ExtendsQueueEntry> iterator = extendsQueue.iterator();
			while ( iterator.hasNext() ) {
				final ExtendsQueueEntry entry = iterator.next();
				final SubclassEntityContainer container = subEntityContainerMap.get( entry.entityItExtends );
				if ( container != null ) {
					// we now have this entity's super, attach it and remove entry from extends queue
					container.add( entry.subClassEntitySource );
					iterator.remove();
					numberOfMappingsProcessed++;
				}
			}

			if ( numberOfMappingsProcessed == 0 ) {
				// todo : we could log the waiting dependencies...
				throw new MappingException( "Unable to process extends dependencies in hbm files" );
			}
		}

		return entityHierarchies;
	}

	private void processSubElements(EntityElement entityElement, SubclassEntityContainer container) {
		if ( XMLHibernateMapping.XMLClass.class.isInstance( entityElement ) ) {
			final XMLHibernateMapping.XMLClass xmlClass = (XMLHibernateMapping.XMLClass) entityElement;
			processElements( xmlClass.getJoinedSubclass(), container );
			processElements( xmlClass.getSubclass(), container );
			processElements( xmlClass.getUnionSubclass(), container );
		}
		else if ( XMLSubclassElement.class.isInstance( entityElement ) ) {
			final XMLSubclassElement xmlSubclass = (XMLSubclassElement) entityElement;
			processElements( xmlSubclass.getSubclass(), container );
		}
		else if ( XMLJoinedSubclassElement.class.isInstance( entityElement ) ) {
			final XMLJoinedSubclassElement xmlJoinedSubclass = (XMLJoinedSubclassElement) entityElement;
			processElements( xmlJoinedSubclass.getJoinedSubclass(), container );
		}
		else if ( XMLUnionSubclassElement.class.isInstance( entityElement ) ) {
			final XMLUnionSubclassElement xmlUnionSubclass = (XMLUnionSubclassElement) entityElement;
			processElements( xmlUnionSubclass.getUnionSubclass(), container );
		}
	}

	private void processElements(List subElements, SubclassEntityContainer container) {
		for ( Object subElementO : subElements ) {
			final SubEntityElement subElement = (SubEntityElement) subElementO;
			final SubclassEntitySourceImpl subclassEntitySource = new SubclassEntitySourceImpl( currentMappingDocument, subElement );
			container.add( subclassEntitySource );
			final String subEntityName = subclassEntitySource.getEntityName();
			subEntityContainerMap.put( subEntityName, subclassEntitySource );
		}
	}

	private static class ExtendsQueueEntry {
		private final SubclassEntitySource subClassEntitySource;
		private final String entityItExtends;

		private ExtendsQueueEntry(SubclassEntitySource subClassEntitySource, String entityItExtends) {
			this.subClassEntitySource = subClassEntitySource;
			this.entityItExtends = entityItExtends;
		}
	}
}

Other Hibernate examples (source code examples)

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