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Hibernate example source code file (JoinHelper.java)

This example Hibernate source code file (JoinHelper.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

associationtype, associationtype, joinable, joinhelper, mapping, mapping, outerjoinloadable, outerjoinloadable, propertymapping, sessionfactoryimplementor, string, string

The Hibernate JoinHelper.java source code

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2008-2011, 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.engine.internal;

import org.hibernate.engine.spi.Mapping;
import org.hibernate.engine.spi.SessionFactoryImplementor;
import org.hibernate.internal.util.StringHelper;
import org.hibernate.internal.util.collections.ArrayHelper;
import org.hibernate.persister.entity.Joinable;
import org.hibernate.persister.entity.OuterJoinLoadable;
import org.hibernate.persister.entity.PropertyMapping;
import org.hibernate.type.AssociationType;

/**
 * @author Gavin King
 */
public final class JoinHelper {
	
	private JoinHelper() {}
	
	/**
	 * Get the aliased columns of the owning entity which are to 
	 * be used in the join
	 */
	public static String[] getAliasedLHSColumnNames(
			AssociationType type, 
			String alias, 
			int property, 
			OuterJoinLoadable lhsPersister,
			Mapping mapping
	) {
		return getAliasedLHSColumnNames(type, alias, property, 0, lhsPersister, mapping);
	}
	
	/**
	 * Get the columns of the owning entity which are to 
	 * be used in the join
	 */
	public static String[] getLHSColumnNames(
			AssociationType type, 
			int property, 
			OuterJoinLoadable lhsPersister,
			Mapping mapping
	) {
		return getLHSColumnNames(type, property, 0, lhsPersister, mapping);
	}
	
	/**
	 * Get the aliased columns of the owning entity which are to 
	 * be used in the join
	 */
	public static String[] getAliasedLHSColumnNames(
			AssociationType type, 
			String alias, 
			int property, 
			int begin, 
			OuterJoinLoadable lhsPersister,
			Mapping mapping
	) {
		if ( type.useLHSPrimaryKey() ) {
			return StringHelper.qualify( alias, lhsPersister.getIdentifierColumnNames() );
		}
		else {
			String propertyName = type.getLHSPropertyName();
			if (propertyName==null) {
				return ArrayHelper.slice( 
						lhsPersister.toColumns(alias, property), 
						begin, 
						type.getColumnSpan(mapping) 
					);
			}
			else {
				return ( (PropertyMapping) lhsPersister ).toColumns(alias, propertyName); //bad cast
			}
		}
	}
	
	/**
	 * Get the columns of the owning entity which are to 
	 * be used in the join
	 */
	public static String[] getLHSColumnNames(
			AssociationType type, 
			int property, 
			int begin, 
			OuterJoinLoadable lhsPersister,
			Mapping mapping
	) {
		if ( type.useLHSPrimaryKey() ) {
			//return lhsPersister.getSubclassPropertyColumnNames(property);
			return lhsPersister.getIdentifierColumnNames();
		}
		else {
			String propertyName = type.getLHSPropertyName();
			if (propertyName==null) {
				//slice, to get the columns for this component
				//property
				return ArrayHelper.slice( 
						lhsPersister.getSubclassPropertyColumnNames(property),
						begin, 
						type.getColumnSpan(mapping) 
					);
			}
			else {
				//property-refs for associations defined on a
				//component are not supported, so no need to slice
				return lhsPersister.getPropertyColumnNames(propertyName);
			}
		}
	}
	
	public static String getLHSTableName(
		AssociationType type, 
		int property, 
		OuterJoinLoadable lhsPersister
	) {
		if ( type.useLHSPrimaryKey() ) {
			return lhsPersister.getTableName();
		}
		else {
			String propertyName = type.getLHSPropertyName();
			if (propertyName==null) {
				//if there is no property-ref, assume the join
				//is to the subclass table (ie. the table of the
				//subclass that the association belongs to)
				return lhsPersister.getSubclassPropertyTableName(property);
			}
			else {
				//handle a property-ref
				String propertyRefTable = lhsPersister.getPropertyTableName(propertyName);
				if (propertyRefTable==null) {
					//it is possible that the tree-walking in OuterJoinLoader can get to
					//an association defined by a subclass, in which case the property-ref
					//might refer to a property defined on a subclass of the current class
					//in this case, the table name is not known - this temporary solution 
					//assumes that the property-ref refers to a property of the subclass
					//table that the association belongs to (a reasonable guess)
					//TODO: fix this, add: OuterJoinLoadable.getSubclassPropertyTableName(String propertyName)
					propertyRefTable = lhsPersister.getSubclassPropertyTableName(property);
				}
				return propertyRefTable;
			}
		}
	}
	
	/**
	 * Get the columns of the associated table which are to 
	 * be used in the join
	 */
	public static String[] getRHSColumnNames(AssociationType type, SessionFactoryImplementor factory) {
		String uniqueKeyPropertyName = type.getRHSUniqueKeyPropertyName();
		Joinable joinable = type.getAssociatedJoinable(factory);
		if (uniqueKeyPropertyName==null) {
			return joinable.getKeyColumnNames();
		}
		else {
			return ( (OuterJoinLoadable) joinable ).getPropertyColumnNames(uniqueKeyPropertyName);
		}
	}
}

Other Hibernate examples (source code examples)

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