Package edu.uci.ics.jung.graph.util

Class DefaultParallelEdgeIndexFunction<V,E>

java.lang.Object

edu.uci.ics.jung.graph.util.DefaultParallelEdgeIndexFunction<V,E>

All Implemented Interfaces:

EdgeIndexFunction<V,E>

public class DefaultParallelEdgeIndexFunction<V,E>
extends java.lang.Object
implements EdgeIndexFunction<V,E>

A class which creates and maintains indices for parallel edges. Parallel edges are defined here to be the collection of edges that are returned by v.findEdgeSet(w) for some v and w.

At this time, users are responsible for resetting the indices (by calling reset()) if changes to the graph make it appropriate.

Field Summary

Fields

Modifier and Type	Field	Description
protected java.util.Map<Context<Graph<V,E>,E>,java.lang.Integer>	edge_index

Constructor Summary

Constructors

Modifier	Constructor	Description
private	DefaultParallelEdgeIndexFunction()

Method Summary

Modifier and Type	Method	Description
int	getIndex(Graph<V,E> graph, E e)	Returns the index for e in graph.
protected int	getIndex(Graph<V,E> graph, E e, V v)
protected int	getIndex(Graph<V,E> graph, E e, V v, V u)
static <V,E> DefaultParallelEdgeIndexFunction<V,E>	getInstance()
void	reset()	Clears all edge indices for all edges in all graphs.
void	reset(Graph<V,E> graph, E e)	Resets the indices for this edge and its parallel edges.

Methods inherited from class java.lang.Object

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

Field Detail

edge_index

protected java.util.Map<Context<Graph<V,E>,E>,java.lang.Integer> edge_index

Constructor Detail

DefaultParallelEdgeIndexFunction

private DefaultParallelEdgeIndexFunction()

Method Detail

getInstance

public static <V,E> DefaultParallelEdgeIndexFunction<V,E> getInstance()

Type Parameters:

V - the vertex type

E - the edge type

Returns:

an instance of this class

getIndex

public int getIndex(Graph<V,E> graph,
                    E e)

Returns the index for e in graph. Calculates the indices for e and for all edges parallel to e, if they are not already assigned.

Specified by:

getIndex in interface EdgeIndexFunction<V,E>

Parameters:

graph - the graph with respect to which the index is calculated

e - the edge whose index is to be queried

Returns:

e's index in graph

getIndex

protected int getIndex(Graph<V,E> graph,
                       E e,
                       V v,
                       V u)

getIndex

protected int getIndex(Graph<V,E> graph,
                       E e,
                       V v)

reset

public void reset(Graph<V,E> graph,
                  E e)

Resets the indices for this edge and its parallel edges. Should be invoked when an edge parallel to e has been added or removed.

Specified by:

reset in interface EdgeIndexFunction<V,E>

Parameters:

graph - the graph for which the indices are to be reset

e - the edge whose indices are to be reset

reset

public void reset()

Clears all edge indices for all edges in all graphs. Does not recalculate the indices.

Specified by:

reset in interface EdgeIndexFunction<V,E>