//$Id: QueryLoader.java 14268 2008-01-07 13:43:04Z epbernard $
package org.hibernate.search.engine;
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.Criteria;
import org.hibernate.Hibernate;
import org.hibernate.Session;
import org.hibernate.annotations.common.AssertionFailure;
import org.hibernate.criterion.Disjunction;
import org.hibernate.criterion.Restrictions;
/**
* @author Emmanuel Bernard
*/
public class QueryLoader implements Loader {
private static final int MAX_IN_CLAUSE = 500;
private static final List EMPTY_LIST = new ArrayList( 0 );
private static Log log = LogFactory.getLog( QueryLoader.class );
private Session session;
private Class entityType;
private SearchFactoryImplementor searchFactoryImplementor;
private Criteria criteria;
public void init(Session session, SearchFactoryImplementor searchFactoryImplementor) {
this.session = session;
this.searchFactoryImplementor = searchFactoryImplementor;
}
public void setEntityType(Class entityType) {
this.entityType = entityType;
}
public Object load(EntityInfo entityInfo) {
//be sure to get an initialized object
Object maybeProxy = session.get( entityInfo.clazz, entityInfo.id );
try {
Hibernate.initialize( maybeProxy );
}
catch (RuntimeException e) {
if ( LoaderHelper.isObjectNotFoundException( e ) ) {
log.debug( "Object found in Search index but not in database: "
+ entityInfo.clazz + " wih id " + entityInfo.id );
maybeProxy = null;
}
else {
throw e;
}
}
return maybeProxy;
}
public List load(EntityInfo... entityInfos) {
final int maxResults = entityInfos.length;
if ( maxResults == 0 ) return EMPTY_LIST;
if ( entityType == null ) throw new AssertionFailure( "EntityType not defined" );
if ( criteria == null ) criteria = session.createCriteria( entityType );
DocumentBuilder builder = searchFactoryImplementor.getDocumentBuilders().get( entityType );
String idName = builder.getIdentifierName();
int loop = maxResults / MAX_IN_CLAUSE;
boolean exact = maxResults % MAX_IN_CLAUSE == 0;
if ( !exact ) loop++;
Disjunction disjunction = Restrictions.disjunction();
for (int index = 0; index < loop; index++) {
int max = index * MAX_IN_CLAUSE + MAX_IN_CLAUSE <= maxResults ?
index * MAX_IN_CLAUSE + MAX_IN_CLAUSE :
maxResults;
List ids = new ArrayList( max - index * MAX_IN_CLAUSE );
for (int entityInfoIndex = index * MAX_IN_CLAUSE; entityInfoIndex < max; entityInfoIndex++) {
ids.add( entityInfos[entityInfoIndex].id );
}
disjunction.add( Restrictions.in( idName, ids ) );
}
criteria.add( disjunction );
criteria.list(); //load all objects
//mandatory to keep the same ordering
List result = new ArrayList( entityInfos.length );
for (EntityInfo entityInfo : entityInfos) {
Object element = session.load( entityInfo.clazz, entityInfo.id );
if ( Hibernate.isInitialized( element ) ) {
//all existing elements should have been loaded by the query,
//the other ones are missing ones
result.add( element );
}
}
return result;
}
public void setCriteria(Criteria criteria) {
this.criteria = criteria;
}
}