com.net2plan.libraries

Class GraphUtils.JGraphTUtils

Object

com.net2plan.libraries.GraphUtils.JGraphTUtils

Enclosing class:

GraphUtils

public static class GraphUtils.JGraphTUtils
extends Object

Auxiliary class to work with the graph library JGraphT.

Since:

0.2.0

Author:

Pablo Pavon-Marino, Jose-Luis Izquierdo-Zaragoza

Constructor Summary

Constructors

Constructor and Description
GraphUtils.JGraphTUtils()

Method Summary

Methods

Modifier and Type	Method and Description
static org.jgrapht.Graph<Long,Long>	buildAuxiliaryNodeDisjointGraph(org.jgrapht.Graph<Long,Long> graph, long originNode, long destinationNode) Builds an auxiliary graph for the application of edge-disjoint shortest-path pair algorithms to node-disjoint problems.
static <V,E> org.jgrapht.WeightedGraph<V,E>	getAsWeightedGraph(org.jgrapht.Graph<V,E> graph, Map<E,Double> edgeWeightMap) It generates a weighted view of the backing graph specified in the constructor.
static org.jgrapht.Graph<Long,Long>	getGraphFromLinkMap(Map<Long,Pair<Long,Long>> linkMap) Obtains a JGraphT graph from a given link map.
static org.jgrapht.Graph<Long,Long>	getGraphFromLinkMap(Set<Long> nodeIds, Map<Long,Pair<Long,Long>> linkMap) Obtains a JGraphT graph from a given link map.
static boolean	isBidirectional(org.jgrapht.Graph graph) Check whether the topology has the same number of links between each node pair in both directions (assuming multi-digraphs).
static boolean	isConnected(org.jgrapht.Graph graph) Check whether the graph is connected, that is, if it is possible to connect every node to each other.
static boolean	isConnected(org.jgrapht.Graph graph, Set vertices) Check whether the graph is connected, that is, if it is possible to connect every node to each other, but only in a subset of vertices (subgraph).
static boolean	isSimple(org.jgrapht.Graph graph) Check whether the graph is simple, that is, if it has at most one link between each node pair (one per direction under directed graphs, one under undirected graphs).
static boolean	isWeightedBidirectional(org.jgrapht.Graph graph) Checks whether the graph has the same number of links between each node pair in both directions (assuming multi-digraphs) and same individual weights per direction.

Methods inherited from class Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GraphUtils.JGraphTUtils

public GraphUtils.JGraphTUtils()

Method Detail

buildAuxiliaryNodeDisjointGraph

public static org.jgrapht.Graph<Long,Long> buildAuxiliaryNodeDisjointGraph(org.jgrapht.Graph<Long,Long> graph,
                                                           long originNode,
                                                           long destinationNode)

Builds an auxiliary graph for the application of edge-disjoint shortest-path pair algorithms to node-disjoint problems.

Parameters:

graph - Graph representing the network

originNode - Origin node

destinationNode - Destination node

Returns:

Auxiliary graph

Since:

0.3.0

getAsWeightedGraph

public static <V,E> org.jgrapht.WeightedGraph<V,E> getAsWeightedGraph(org.jgrapht.Graph<V,E> graph,
                                                      Map<E,Double> edgeWeightMap)

It generates a weighted view of the backing graph specified in the constructor. This graph allows modules to apply algorithms designed for weighted graphs to an unweighted graph by providing an explicit edge weight mapping.

Query operations on this graph "read through" to the backing graph. Vertex addition/removal and edge addition/removal are supported.

Type Parameters:

V - Vertex type

E - Edge type

Parameters:

graph - The backing graph over which a weighted view is to be created

edgeWeightMap - A mapping of edges to weights (null means all to one)

Returns:

Returns a weighted view of the backing graph specified in the constructor

Since:

0.3.0

getGraphFromLinkMap

public static org.jgrapht.Graph<Long,Long> getGraphFromLinkMap(Map<Long,Pair<Long,Long>> linkMap)

Obtains a JGraphT graph from a given link map.

Parameters:

linkMap - Map of links, where the key is the unique link identifier and the value is a Pair representing the origin node and the destination node of the link, respectively. Origin/destination nodes will be added as needed

Returns:

JGraphT graph

Since:

0.3.0

getGraphFromLinkMap

public static org.jgrapht.Graph<Long,Long> getGraphFromLinkMap(Set<Long> nodeIds,
                                               Map<Long,Pair<Long,Long>> linkMap)

Obtains a JGraphT graph from a given link map.

Parameters:

nodeIds - Set of node identifiers

linkMap - Map of links, where the key is the unique link identifier and the value is a Pair representing the origin node and the destination node of the link, respectively. Only links whose end-nodes are in nodeIds will be added to the graph

Returns:

JGraphT graph

Since:

0.3.0

isBidirectional

public static boolean isBidirectional(org.jgrapht.Graph graph)

Check whether the topology has the same number of links between each node pair in both directions (assuming multi-digraphs).

Parameters:

graph - The graph to analyze

Returns:

true if the graph is bidirectional, and false otherwise

Since:

0.2.0

isConnected

public static boolean isConnected(org.jgrapht.Graph graph)

Check whether the graph is connected, that is, if it is possible to connect every node to each other.

Parameters:

graph - The graph to analyze

Returns:

true if the graph is connected, and false otherwise

Since:

0.2.0

isConnected

public static boolean isConnected(org.jgrapht.Graph graph,
                  Set vertices)

Check whether the graph is connected, that is, if it is possible to connect every node to each other, but only in a subset of vertices (subgraph).

Parameters:

graph - The graph to analyze

vertices - Subset of vertices

Returns:

true if the subgraph is connected, and false otherwise

Since:

0.2.0

isSimple

public static boolean isSimple(org.jgrapht.Graph graph)

Check whether the graph is simple, that is, if it has at most one link between each node pair (one per direction under directed graphs, one under undirected graphs).

Parameters:

graph - The graph to analyze

Returns:

true if the graph is simple, and false otherwise

Since:

0.2.0

isWeightedBidirectional

public static boolean isWeightedBidirectional(org.jgrapht.Graph graph)

Checks whether the graph has the same number of links between each node pair in both directions (assuming multi-digraphs) and same individual weights per direction.

Parameters:

graph - The graph to analyze

Returns:

true if the graph is weighted-bidirectional, and false otherwise. By convention returns false if network is empty

Since:

0.2.0