public void union(AbstractBaseGraph<V, E> g2) {
if (!(this instanceof DirectedGraph<?, ?> && g2 instanceof DirectedGraph<?, ?>)) {
return;
}
Set<V> vertexSet = g2.vertexSet();
for (V vertex : vertexSet) {
if (!containsVertex(vertex)) addVertex(vertex);
}
for (V vertex : vertexSet) {
Set<E> edgeSet = g2.specifics.outgoingEdgesOf(vertex);
for (E edge : edgeSet) {
V sourceVertex = getEdgeSource(edge);
V targetVertex = getEdgeTarget(edge);
if (!allowingMultipleEdges && containsEdge(sourceVertex, targetVertex)) {
continue;
}
if (!allowingLoops && sourceVertex.equals(targetVertex)) {
continue;
}
if (containsEdge(edge)) {
continue;
} else {
IntrusiveEdge intrusiveEdge = createIntrusiveEdge(edge, sourceVertex, targetVertex);
edgeMap.put(edge, intrusiveEdge);
specifics.addEdgeToTouchingVertices(edge);
}
}
}
}
/**
* Returns a shallow copy of this graph instance. Neither edges nor vertices are cloned.
*
* @return a shallow copy of this set.
* @throws RuntimeException
* @see java.lang.Object#clone()
*/
public Object clone() {
try {
TypeUtil<AbstractBaseGraph<V, E>> typeDecl = null;
AbstractBaseGraph<V, E> newGraph = TypeUtil.uncheckedCast(super.clone(), typeDecl);
newGraph.edgeMap = new LinkedHashMap<E, IntrusiveEdge>();
newGraph.edgeFactory = this.edgeFactory;
newGraph.unmodifiableEdgeSet = null;
newGraph.unmodifiableVertexSet = null;
// NOTE: it's important for this to happen in an object
// method so that the new inner class instance gets associated with
// the right outer class instance
newGraph.specifics = newGraph.createSpecifics();
Graphs.addGraph(newGraph, this);
return newGraph;
} catch (CloneNotSupportedException e) {
e.printStackTrace();
throw new RuntimeException();
}
}