private void selectEdge(AttributedEdge edge) {
		viewer.getSelectedEdgeState().select(edge);
		AttributedVertex source = graph.getEdgeSource(edge);
		AttributedVertex target = graph.getEdgeTarget(edge);
		viewer.getSelectedVertexState().select(Set.of(source, target));
	}
Gather all source and target vertices until there are no more available.
@return all the vertices in the component(s) of the selected vertices
Ghidra/Features/GraphServices/src/main/java/ghidra/graph/visualization/DefaultGraphDisplay.java