/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jena.sparql.engine.main.iterator;
import org.apache.jena.atlas.io.IndentedWriter ;
import org.apache.jena.atlas.lib.Lib ;
import org.apache.jena.sparql.algebra.Op ;
import org.apache.jena.sparql.engine.ExecutionContext ;
import org.apache.jena.sparql.engine.QueryIterator ;
import org.apache.jena.sparql.engine.binding.Binding ;
import org.apache.jena.sparql.engine.iterator.QueryIterDefaulting ;
import org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply ;
import org.apache.jena.sparql.engine.iterator.QueryIterSingleton ;
import org.apache.jena.sparql.engine.main.QC ;
import org.apache.jena.sparql.serializer.SerializationContext ;
public class QueryIterOptionalIndex extends QueryIterRepeatApply
{
private Op op ;
public QueryIterOptionalIndex(QueryIterator input, Op op, ExecutionContext context)
{
super(input, context) ;
this.op = op ;
}
@Override
protected QueryIterator nextStage(Binding binding)
{
Op op2 = QC.substitute(op, binding) ;
QueryIterator thisStep = QueryIterSingleton.create(binding, getExecContext()) ;
QueryIterator cIter = QC.execute(op2, thisStep, super.getExecContext()) ;
cIter = new QueryIterDefaulting(cIter, binding, getExecContext()) ;
return cIter ;
}
@Override
protected void details(IndentedWriter out, SerializationContext sCxt)
{
out.println(Lib.className(this)) ;
out.incIndent() ;
op.output(out, sCxt) ;
out.decIndent() ;
}
}