if (vertex != null && startVertex != null) {
Graph<Device, Connection> graph = vv.getGraphLayout().getGraph();
Connection newEdge = edgeFactory.create();
graph.addEdge(newEdge, startVertex, vertex, edgeIsDirected);
if (startVertex.equals(vertex)) {
new InterfaceProperties(owner, vertex.getInterfaceFor(newEdge));
} else {
new ConnectionProperties(owner, newEdge);
}
vv.repaint();
}