org.apache.xmlgraphics.util.dijkstra
Class DefaultEdgeDirectory

java.lang.Object
  org.apache.xmlgraphics.util.dijkstra.DefaultEdgeDirectory

All Implemented Interfaces:

EdgeDirectory

public class DefaultEdgeDirectory
extends Object
implements EdgeDirectory

Default implementation of an edge directory for the DijkstraAlgorithm.

Constructor Summary

DefaultEdgeDirectory()

Method Summary

void	addEdge(Edge edge) Adds a new edge between two vertices.
Edge	getBestEdge(Vertex start, Vertex end) Returns the best edge (the edge with the lowest penalty) between two given vertices.
Iterator	getDestinations(Vertex origin) Returns an iterator over all valid destinations for a given vertex.
Iterator	getEdges(Vertex origin) Returns an iterator over all edges with the given origin.
int	getPenalty(Vertex start, Vertex end) Returns the penalty between two vertices.

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultEdgeDirectory

public DefaultEdgeDirectory()

Method Detail

addEdge

public void addEdge(Edge edge)

Adds a new edge between two vertices.

Parameters:

edge - the new edge

getPenalty

public int getPenalty(Vertex start,
                      Vertex end)

Returns the penalty between two vertices.

Specified by:

getPenalty in interface EdgeDirectory

Parameters:

start - the start vertex

end - the end vertex

Returns:

the penalty between two vertices, or 0 if no single edge between the two vertices exists.

getDestinations

public Iterator getDestinations(Vertex origin)

Returns an iterator over all valid destinations for a given vertex.

Specified by:

getDestinations in interface EdgeDirectory

Parameters:

origin - the origin from which to search for destinations

Returns:

the iterator over all valid destinations for a given vertex

getEdges

public Iterator getEdges(Vertex origin)

Returns an iterator over all edges with the given origin.

Parameters:

origin - the origin

Returns:

an iterator over Edge instances

getBestEdge

public Edge getBestEdge(Vertex start,
                        Vertex end)

Returns the best edge (the edge with the lowest penalty) between two given vertices.

Parameters:

start - the start vertex

end - the end vertex

Returns:

the best vertex or null if none is found