org.jgrapht.generate

Class RandomGraphGenerator<V,E>

java.lang.Object

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

All Implemented Interfaces:

GraphGenerator<V,E,V>

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

This Generator creates a random-topology graph of a specified number of vertexes and edges. An instance of this generator will always return the same graph-topology in calls to generateGraph(). The vertexes can be different (depends on the VertexFactory implementation)

However, two instances which use the same constructor parameters will produce two different random graphs (note: as with any random generator, there is always a small possibility that two instances will create the same results).

Since:

Aug 6, 2005

Author:

Assaf Lehr

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	RandomGraphGenerator.DefaultEdgeTopologyFactory<VV,EE> Default implementation of the EdgeTopologyFactory interface.
static interface	RandomGraphGenerator.EdgeTopologyFactory<VV,EE> This class is used to generate the edge topology for a graph.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	numOfEdges
protected int	numOfVertexes
protected Random	randomizer

Constructor Summary

Constructors

Constructor and Description
RandomGraphGenerator(int aNumOfVertexes, int aNumOfEdges)
RandomGraphGenerator(int aNumOfVertexes, int aNumOfEdges, long seed)

Method Summary

Methods

Modifier and Type	Method and Description
void	generateGraph(Graph<V,E> target, VertexFactory<V> vertexFactory, Map<String,V> resultMap) (non-Javadoc)
long	getRandomSeed()

Methods inherited from class java.lang.Object

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

Field Detail

numOfVertexes

protected int numOfVertexes

numOfEdges

protected int numOfEdges

randomizer

protected Random randomizer

Constructor Detail

RandomGraphGenerator

public RandomGraphGenerator(int aNumOfVertexes,
                    int aNumOfEdges)

RandomGraphGenerator

public RandomGraphGenerator(int aNumOfVertexes,
                    int aNumOfEdges,
                    long seed)

Method Detail

getRandomSeed

public long getRandomSeed()

generateGraph

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

(non-Javadoc)

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)

Throws:

IllegalArgumentException - if the aNumOfEdges passed in the constructor, cannot be created on a graph of the concrete type with aNumOfVertexes. org.jgrapht.generate.RandomGraphGenerator.DefaultEdgeTopologyFactory#isNumberOfEdgesValid(org.jgrapht.Graph, int)

See Also:

GraphGenerator.generateGraph(Graph, VertexFactory, Map)