public void setVertex(String vertexName) {
    logger.debug("Setting vertex to: '" + vertexName + "'");
    Vertex e = model.findVertex(vertexName);
    Util.AbortIf(e == null, "Vertex not Found: '" + vertexName + "'");

    currentVertex = e;
    setAsVisited(e);
  }
 public boolean hasVertex(String vertexName) {
   return model.findVertex(vertexName) != null;
 }