public void removeSuccessor(StatEdge edge) {

    if (edge == null) {
      return;
    }

    removeEdgeInternal(EdgeDirection.FORWARD, edge);

    if (edge.closure != null) {
      edge.closure.getLabelEdges().remove(edge);
    }

    if (edge.getDestination() != null) {  // TODO: redundant?
      edge.getDestination().removePredecessor(edge);
    }
  }
public void removeSuccessor(StatEdge edge)