public Optional<BlazeVertex> vertex(final String vertexId){
  try (final CloseableIterator<Vertex> it=vertices(vertexId)){
    final Optional<BlazeVertex> v=it.hasNext() ? Optional.of((BlazeVertex)it.next()) : Optional.empty();
    if (it.hasNext()) {
      throw new IllegalStateException("Multiple vertices found with id: " + vertexId);
    }
    return v;
  }
 }

public Optional < BlazeVertex > vertex ( final String vertexId ) { try ( final CloseableIterator < Vertex > it = vertices ( vertexId ) ) { final Optional < BlazeVertex > v = it . hasNext ( ) ? Optional . of ( ( BlazeVertex ) it . next ( ) ) : Optional . empty ( ) ; if ( it . hasNext ( ) ) { throw new IllegalStateException ( "Multiple vertices found with id: " + vertexId ) ; } return v ; } }
lookup a vertex by id .
