public void execute() {
if (nodes.length > 1) {
GraphElementsController gec = Lookup.getDefault().lookup(GraphElementsController.class);
gec.createEdges(sourceNode, nodes, directed);
}else{
AddEdgeToGraph manipulator = new AddEdgeToGraph();
manipulator.setSource(sourceNode);
DataLaboratoryHelper.getDefault().executeManipulator(manipulator);
}
}