//$Id: CollectionElementLoader.java 9636 2006-03-16 14:14:48Z [email protected] $
package org.hibernate.loader.entity;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.HibernateException;
import org.hibernate.LockMode;
import org.hibernate.MappingException;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.engine.SessionImplementor;
import org.hibernate.loader.JoinWalker;
import org.hibernate.loader.OuterJoinLoader;
import org.hibernate.persister.collection.QueryableCollection;
import org.hibernate.persister.entity.OuterJoinLoadable;
import org.hibernate.transform.ResultTransformer;
import org.hibernate.type.Type;
import org.hibernate.util.ArrayHelper;
/**
*
*
* @author Gavin King
*/
public class CollectionElementLoader extends OuterJoinLoader {
private static final Log log = LogFactory.getLog(CollectionElementLoader.class);
private final OuterJoinLoadable persister;
private final Type keyType;
private final Type indexType;
private final String entityName;
public CollectionElementLoader(
QueryableCollection collectionPersister,
SessionFactoryImplementor factory,
Map enabledFilters)
throws MappingException {
super(factory, enabledFilters);
this.keyType = collectionPersister.getKeyType();
this.indexType = collectionPersister.getIndexType();
this.persister = (OuterJoinLoadable) collectionPersister.getElementPersister();
this.entityName = persister.getEntityName();
JoinWalker walker = new EntityJoinWalker(
persister,
ArrayHelper.join(
collectionPersister.getKeyColumnNames(),
collectionPersister.getIndexColumnNames()
),
1,
LockMode.NONE,
factory,
enabledFilters
);
initFromWalker( walker );
postInstantiate();
log.debug( "Static select for entity " + entityName + ": " + getSQLString() );
}
public Object loadElement(SessionImplementor session, Object key, Object index)
throws HibernateException {
List list = loadEntity(
session,
key,
index,
keyType,
indexType,
persister
);
if ( list.size()==1 ) {
return list.get(0);
}
else if ( list.size()==0 ) {
return null;
}
else {
if ( getCollectionOwners()!=null ) {
return list.get(0);
}
else {
throw new HibernateException("More than one row was found");
}
}
}
protected Object getResultColumnOrRow(
Object[] row,
ResultTransformer transformer,
ResultSet rs, SessionImplementor session)
throws SQLException, HibernateException {
return row[row.length-1];
}
protected boolean isSingleRowLoader() {
return true;
}
}
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