org.jscience.computing.graph.generators
Class WheelGraphGenerator

java.lang.Object
  extended by org.jscience.computing.graph.generators.WheelGraphGenerator
All Implemented Interfaces:
GraphGenerator

public class WheelGraphGenerator
extends java.lang.Object
implements GraphGenerator

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

Field Summary
static java.lang.String HUB_VERTEX
          Role for the hub vertex.
 
Constructor Summary
WheelGraphGenerator(int size)
          Creates a new WheelGraphGenerator object.
WheelGraphGenerator(int size, boolean inwardSpokes)
          Construct a new WheelGraphGenerator.
 
Method Summary
 void generateGraph(Graph target, VertexFactory vertexFactory, java.util.Map 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 java.lang.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:
java.lang.IllegalArgumentException
Method Detail

generateGraph

public void generateGraph(Graph target,
                          VertexFactory vertexFactory,
                          java.util.Map 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
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)