org.hibernate.impl.IteratorImpl Maven / Gradle / Ivy
/*
* 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.impl;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.NoSuchElementException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.hibernate.HibernateException;
import org.hibernate.JDBCException;
import org.hibernate.engine.HibernateIterator;
import org.hibernate.event.EventSource;
import org.hibernate.exception.JDBCExceptionHelper;
import org.hibernate.hql.HolderInstantiator;
import org.hibernate.type.EntityType;
import org.hibernate.type.Type;
/**
* An implementation of java.util.Iterator that is
* returned by iterate() query execution methods.
* @author Gavin King
*/
public final class IteratorImpl implements HibernateIterator {
private static final Logger log = LoggerFactory.getLogger(IteratorImpl.class);
private ResultSet rs;
private final EventSource session;
private boolean readOnly;
private final Type[] types;
private final boolean single;
private Object currentResult;
private boolean hasNext;
private final String[][] names;
private PreparedStatement ps;
private HolderInstantiator holderInstantiator;
public IteratorImpl(
ResultSet rs,
PreparedStatement ps,
EventSource sess,
boolean readOnly,
Type[] types,
String[][] columnNames,
HolderInstantiator holderInstantiator)
throws HibernateException, SQLException {
this.rs=rs;
this.ps=ps;
this.session = sess;
this.readOnly = readOnly;
this.types = types;
this.names = columnNames;
this.holderInstantiator = holderInstantiator;
single = types.length==1;
postNext();
}
public void close() throws JDBCException {
if (ps!=null) {
try {
log.debug("closing iterator");
session.getBatcher().closeQueryStatement(ps, rs);
ps = null;
rs = null;
hasNext = false;
}
catch (SQLException e) {
log.info( "Unable to close iterator", e );
throw JDBCExceptionHelper.convert(
session.getFactory().getSQLExceptionConverter(),
e,
"Unable to close iterator"
);
}
finally {
try {
session.getPersistenceContext().getLoadContexts().cleanup( rs );
}
catch( Throwable ignore ) {
// ignore this error for now
log.trace( "exception trying to cleanup load context : " + ignore.getMessage() );
}
}
}
}
private void postNext() throws SQLException {
log.debug("attempting to retrieve next results");
this.hasNext = rs.next();
if (!hasNext) {
log.debug("exhausted results");
close();
}
else {
log.debug("retrieved next results");
}
}
public boolean hasNext() {
return hasNext;
}
public Object next() throws HibernateException {
if ( !hasNext ) throw new NoSuchElementException("No more results");
boolean sessionDefaultReadOnlyOrig = session.isDefaultReadOnly();
session.setDefaultReadOnly( readOnly );
try {
boolean isHolder = holderInstantiator.isRequired();
log.debug("assembling results");
if ( single && !isHolder ) {
currentResult = types[0].nullSafeGet( rs, names[0], session, null );
}
else {
Object[] currentResults = new Object[types.length];
for (int i=0; i