Set<Integer> unused = graph.successors(node);
                }
                /*
                 * Also look up an earlier node so that, if the graph is using MapRetrievalCache,
                 * we read one of the fields declared in that class.
                 */
                Set<Integer> unused = graph.successors(first);

                  Set<Integer> unused = graph.successors(node);
                }
                /*
                 * Also look up an earlier node so that, if the graph is using MapRetrievalCache,
                 * we read one of the fields declared in that class.
                 */
                Set<Integer> unused = graph.successors(first);