/*
* 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 com.hp.hpl.jena.sparql.engine.optimizer.reorder;
import com.hp.hpl.jena.graph.Triple ;
import com.hp.hpl.jena.sparql.ARQException ;
import com.hp.hpl.jena.sparql.core.BasicPattern ;
import org.apache.jena.atlas.logging.Log ;
public class ReorderProcIndexes implements ReorderProc
{
private int[] indexes ;
public ReorderProcIndexes(int[] indexes)
{
this.indexes = indexes ;
}
/** Return a new basic pattern with the same triples as the input,
* but ordered as per the index list of this reorder processor.
*/
@Override
public BasicPattern reorder(BasicPattern bgp)
{
if ( indexes.length != bgp.size() )
{
String str = String.format("Expected size = %d : actual basic pattern size = %d", indexes.length, bgp.size()) ;
Log.fatal(this, str) ;
throw new ARQException(str) ;
}
BasicPattern bgp2 = new BasicPattern() ;
for ( int j = 0 ; j < indexes.length ; j++ )
{
int idx = indexes[j] ;
Triple t = bgp.get(idx) ;
bgp2.add(t) ;
}
return bgp2 ;
}
@Override
public String toString()
{
String x = "" ;
String sep = "" ;
for ( int idx : indexes )
{
x = x + sep + idx ;
sep = ", " ;
}
return x;
}
}