/*
* 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 net.hydromatic.optiq.tools;
import org.eigenbase.rel.RelNode;
import org.eigenbase.relopt.RelOptPlanner;
import org.eigenbase.relopt.RelTraitSet;
/**
* Program that transforms a relational expression into another relational
* expression.
*
* <p>A planner is a sequence of programs, each of which is sometimes called
* a "phase".
* The most typical program is an invocation of the volcano planner with a
* particular {@link net.hydromatic.optiq.tools.RuleSet}.</p>
*/
public interface Program {
RelNode run(RelOptPlanner planner, RelNode rel,
RelTraitSet requiredOutputTraits);
}
// End Program.java