package org.ontoware.rdf2go.impl.jena;
import org.ontoware.aifbcommons.collection.ClosableIterator;
import org.ontoware.rdf2go.exception.ModelRuntimeException;
import org.ontoware.rdf2go.model.QueryRow;
import org.ontoware.rdf2go.model.impl.QueryRowImpl;
import com.hp.hpl.jena.query.QuerySolution;
import com.hp.hpl.jena.query.ResultSet;
import com.hp.hpl.jena.rdf.model.RDFNode;
public class QueryIterator implements ClosableIterator<QueryRow> {
private final ResultSet resultSet;
private final QueryResultTableImpl table;
public QueryIterator(QueryResultTableImpl table, ResultSet results) {
this.resultSet = results;
this.table = table;
}
@Override
public boolean hasNext() {
return this.resultSet.hasNext();
}
@Override
/*
* patch from garpinc against nulls -
* http://issues.semweb4j.org/browse/RTGO-65
*/
public QueryRow next() {
QuerySolution qs = this.resultSet.nextSolution();
QueryRowImpl row = new QueryRowImpl();
for(String v : this.table.getVariables()) {
RDFNode node = qs.get(v);
assert node != null : "null node for varname " + v
+ ". Do you have unbound variables in the query?";
try {
row.put(v, TypeConversion.toRDF2Go((node == null ? null : node.asNode())));
} catch(ModelRuntimeException e) {
throw new ModelRuntimeException(e);
}
}
return row;
}
@Override
public void remove() {
this.resultSet.remove();
}
@Override
public void close() {
}
}