/*
* 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.sparql.core.BasicPattern ;
import com.hp.hpl.jena.sparql.engine.optimizer.StatsMatcher ;
public class ReorderLib
{
private static class ReorderProcIdentity implements ReorderProc
{
@Override
public BasicPattern reorder(BasicPattern pattern)
{
return pattern ;
}
@Override
public String toString()
{
return "identity reorder" ;
}
} ;
private static ReorderProc _identityProc = new ReorderProcIdentity() ;
private static class ReorderTransformationIdentity implements ReorderTransformation
{
@Override
public BasicPattern reorder(BasicPattern pattern)
{
return pattern ;
}
@Override
public ReorderProc reorderIndexes(BasicPattern pattern)
{
return _identityProc ;
}
} ;
private static ReorderTransformation _identity = new ReorderTransformationIdentity() ;
public static ReorderProc identityProc()
{ return _identityProc ; }
public static ReorderTransformation identity()
{ return _identity ; }
public static ReorderTransformation fixed()
{
return new ReorderFixed() ;
}
public static ReorderTransformation weighted(String filename)
{
StatsMatcher stats = new StatsMatcher(filename) ;
return new ReorderWeighted(stats) ;
}
}