org.onlab.graph.Weight Maven / Gradle / Ivy
/*
* Copyright 2016-present Open Networking Foundation
*
* 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 org.onlab.graph;
/**
* Abstraction of a graph edge weight.
*/
public interface Weight extends Comparable {
/**
* Merges the given weight with this one returning a new aggregated
* weight.
*
* @param otherWeight weight to add
* @return aggregated weight
*/
Weight merge(Weight otherWeight);
/**
* Subtracts the given weight from this one and produces a new weight.
*
* @param otherWeight weight to subtract
* @return residual weight
*/
Weight subtract(Weight otherWeight);
/**
* Returns true if the weighted subject (link/path) can be traversed; false otherwise.
*
* @return true if weight is adequate, false if weight is infinite
*/
boolean isViable();
/**
* Returns true if the weight is negative (means that aggregated
* path cost will decrease if we add weighted subject to it).
*
* @return true if the weight is negative, false otherwise
*/
boolean isNegative();
}