/** {@inheritDoc} */
public void generateGraph(
Graph<V, E> target, VertexFactory<V> vertexFactory, Map<String, V> resultMap) {
if (size < 1) {
return;
}
// Add all the vertices to the set
for (int i = 0; i < size; i++) {
V newVertex = vertexFactory.createVertex();
target.addVertex(newVertex);
}
/*
* We want two iterators over the vertex set, one fast and one slow.
* The slow one will move through the set once. For each vertex,
* the fast iterator moves through the set, adding an edge to all
* vertices we haven't connected to yet.
*
* If we have an undirected graph, the second addEdge call will return
* nothing; it will not add a second edge.
*/
Iterator<V> slowI = target.vertexSet().iterator();
Iterator<V> fastI;
while (slowI.hasNext()) { // While there are more vertices in the set
V latestVertex = slowI.next();
fastI = target.vertexSet().iterator();
// Jump to the first vertex *past* latestVertex
while (fastI.next() != latestVertex) {;
}
// And, add edges to all remaining vertices
V temp;
while (fastI.hasNext()) {
temp = fastI.next();
target.addEdge(latestVertex, temp);
target.addEdge(temp, latestVertex);
}
}
}
/** {@inheritDoc} */
public void generateGraph(
Graph<V, E> target, final VertexFactory<V> vertexFactory, Map<String, V> resultMap) {
if (size < 1) {
return;
}
// A little trickery to intercept the rim generation. This is
// necessary since target may be initially non-empty, meaning we can't
// rely on its vertex set after the rim is generated.
final Collection<V> rim = new ArrayList<V>();
VertexFactory<V> rimVertexFactory =
new VertexFactory<V>() {
public V createVertex() {
V vertex = vertexFactory.createVertex();
rim.add(vertex);
return vertex;
}
};
RingGraphGenerator<V, E> ringGenerator = new RingGraphGenerator<V, E>(size - 1);
ringGenerator.generateGraph(target, rimVertexFactory, resultMap);
V hubVertex = vertexFactory.createVertex();
target.addVertex(hubVertex);
if (resultMap != null) {
resultMap.put(HUB_VERTEX, hubVertex);
}
for (V rimVertex : rim) {
if (inwardSpokes) {
target.addEdge(rimVertex, hubVertex);
} else {
target.addEdge(hubVertex, rimVertex);
}
}
}
/** {@inheritDoc} */
public void generateGraph(
Graph<V, E> target, VertexFactory<V> vertexFactory, Map<String, V> resultMap) {
V lastVertex = null;
for (int i = 0; i < size; ++i) {
V newVertex = vertexFactory.createVertex();
target.addVertex(newVertex);
if (lastVertex == null) {
if (resultMap != null) {
resultMap.put(START_VERTEX, newVertex);
}
} else {
target.addEdge(lastVertex, newVertex);
}
lastVertex = newVertex;
}
if ((resultMap != null) && (lastVertex != null)) {
resultMap.put(END_VERTEX, lastVertex);
}
}