com.revolsys.jts.edgegraph

Class EdgeGraph

java.lang.Object

com.revolsys.jts.edgegraph.EdgeGraph

public class EdgeGraph
extends Object

A graph comprised of HalfEdges. It supports tracking the vertices in the graph via edges incident on them, to allow efficient lookup of edges and vertices.

This class may be subclassed to use a different subclass of HalfEdge, by overriding createEdge(Point). If additional logic is required to initialize edges then EdgeGraph#addEdge(Coordinates, Point) can be overridden as well.

Author:

Martin Davis

Constructor Summary

Constructors

Constructor and Description
EdgeGraph()

Method Summary

Methods

Modifier and Type	Method and Description
HalfEdge	addEdge(Point orig, Point dest) Adds an edge between the coordinates orig and dest to this graph.
protected HalfEdge	createEdge(Point orig) Creates a single HalfEdge.
HalfEdge	findEdge(Point orig, Point dest) Finds an edge in this graph with the given origin and destination, if one exists.
Collection	getVertexEdges()

Methods inherited from class java.lang.Object

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

Constructor Detail

EdgeGraph

public EdgeGraph()

Method Detail

addEdge

public HalfEdge addEdge(Point orig,
               Point dest)

Adds an edge between the coordinates orig and dest to this graph.

Parameters:

orig - the edge origin location

dest - the edge destination location.

Returns:

the created edge

createEdge

protected HalfEdge createEdge(Point orig)

Creates a single HalfEdge. Override to use a different HalfEdge subclass.

Parameters:

orig - the origin location

Returns:

a new HalfEdge with the given origin

findEdge

public HalfEdge findEdge(Point orig,
                Point dest)

Finds an edge in this graph with the given origin and destination, if one exists.

Parameters:

orig - the origin location

dest - the destination location.

Returns:

an edge with the given orig and dest, or null if none exists

getVertexEdges

public Collection getVertexEdges()