org.jgrapht.generate

Class WheelGraphGenerator<V,E>

java.lang.Object

org.jgrapht.generate.WheelGraphGenerator<V,E>

Type Parameters:

V - the graph vertex type

E - the graph edge type

All Implemented Interfaces:

GraphGenerator<V,E,V>

public class WheelGraphGenerator<V,E>
extends Object
implements GraphGenerator<V,E,V>

Generates a wheel graph of any size. Reminding a bicycle wheel, a wheel graph has a hub vertex in the center and a rim of vertices around it that are connected to each other (as a ring). The rim vertices are also connected to the hub with edges that are called "spokes".

Since:

Sep 16, 2003

Author:

John V. Sichi

Field Summary

Fields

Modifier and Type	Field and Description
static String	HUB_VERTEX Role for the hub vertex.

Constructor Summary

Constructors

Constructor and Description
WheelGraphGenerator(int size) Creates a new WheelGraphGenerator object.
WheelGraphGenerator(int size, boolean inwardSpokes) Construct a new WheelGraphGenerator.

Method Summary

Modifier and Type	Method and Description
void	generateGraph(Graph<V,E> target, VertexFactory<V> vertexFactory, Map<String,V> resultMap) Generate a graph structure.

Methods inherited from class java.lang.Object

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

Field Detail

HUB_VERTEX

public static final String HUB_VERTEX

Role for the hub vertex.

See Also:

Constant Field Values

Constructor Detail

WheelGraphGenerator

public WheelGraphGenerator(int size)

Creates a new WheelGraphGenerator object. This constructor is more suitable for undirected graphs, where spokes' direction is meaningless. In the directed case, spokes will be oriented from rim to hub.

Parameters:

size - number of vertices to be generated.

WheelGraphGenerator

public WheelGraphGenerator(int size,
                           boolean inwardSpokes)

Construct a new WheelGraphGenerator.

Parameters:

size - number of vertices to be generated.

inwardSpokes - if true and graph is directed, spokes are oriented from rim to hub; else from hub to rim.

Throws:

IllegalArgumentException - in case the number of vertices is negative

Method Detail

generateGraph

public void generateGraph(Graph<V,E> target,
                          VertexFactory<V> vertexFactory,
                          Map<String,V> resultMap)

Generate a graph structure. The topology of the generated graph is dependent on the implementation. For graphs in which not all vertices share the same automorphism equivalence class, the generator may produce a labeling indicating the roles played by generated elements. This is the purpose of the resultMap parameter. For example, a generator for a wheel graph would designate a hub vertex. Role names used as keys in resultMap should be declared as public static final Strings by implementation classes.

Specified by:

generateGraph in interface GraphGenerator<V,E,V>

Parameters:

target - receives the generated edges and vertices; if this is non-empty on entry, the result will be a disconnected graph since generated elements will not be connected to existing elements

vertexFactory - called to produce new vertices

resultMap - if non-null, receives implementation-specific mappings from String roles to graph elements (or collections of graph elements)