/*
* #!
* Ontopia Engine
* #-
* Copyright (C) 2001 - 2013 The Ontopia Project
* #-
* Licensed 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.ontopia.topicmaps.query.impl.utils;
import java.util.Set;
import net.ontopia.topicmaps.query.parser.AbstractClause;
public abstract class CostEstimator {
/**
* INTERNAL: Computes the cost of evaluating the given clause
* in the given context of variable bindings. The cost largely
* depends on the number of unbound variables in the clause.
* @param context A set of bound variables.
* @param clause The clause whose cost we want to compute.
* @param literalvars Contains the variables representing literals.
* Only an issue in rules.
* @param rulename The name of the current rule (so we can delay
* recursive evaluation).
*/
public abstract int computeCost(Set context, AbstractClause clause,
Set literalvars, String rulename);
}