/*
* Copyright Aduna (http://www.aduna-software.com/) (c) 1997-2006.
*
* Licensed under the Aduna BSD-style license.
*/
package org.openrdf.rdf2go;
import org.ontoware.aifbcommons.collection.ClosableIterator;
import org.ontoware.rdf2go.exception.ModelRuntimeException;
import org.ontoware.rdf2go.model.QueryRow;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.openrdf.query.BindingSet;
import org.openrdf.query.QueryEvaluationException;
import org.openrdf.query.TupleQueryResult;
/**
* Iterator over an OpenRDF TupleQueryResult that converts its BindingSets to
* RDF2Go QueryRows on demand. This iterator closes automatically after
* returning the last QueryRow.
*/
public class QueryRowIterator implements ClosableIterator<QueryRow> {
final Logger logger = LoggerFactory.getLogger(this.getClass());
private TupleQueryResult queryResult;
private boolean closed = false;
public QueryRowIterator(TupleQueryResult queryResult) {
this.queryResult = queryResult;
}
public boolean hasNext() {
if (this.closed) {
return false;
}
else {
boolean hasNext = false;
try {
hasNext = this.queryResult.hasNext();
}
catch (QueryEvaluationException e) {
throw new ModelRuntimeException(e);
}
if (!hasNext) {
close();
}
return hasNext;
}
}
public QueryRow next() {
BindingSet nextBindingSet = null;
try {
nextBindingSet = this.queryResult.next();
if (!this.queryResult.hasNext()) {
close();
}
}
catch (QueryEvaluationException e) {
throw new ModelRuntimeException(e);
}
return new QueryRowWrapper(nextBindingSet);
}
public void remove() {
try {
this.queryResult.remove();
}
catch (QueryEvaluationException e) {
throw new ModelRuntimeException(e);
}
}
public void close() {
try {
this.queryResult.close();
}
catch (QueryEvaluationException e) {
throw new ModelRuntimeException(e);
}
this.closed = true;
}
@Override
protected void finalize()
throws Throwable
{
try {
if (!this.closed) {
this.logger.warn(this.getClass().getName() + " not closed, closing now");
close();
}
}
finally {
super.finalize();
}
}
}