while (resultWithDoubleSelfLoop.hasNext()) {
          EndpointPair<N> edge = resultWithDoubleSelfLoop.next();
          if (edge.nodeU().equals(edge.nodeV())) {
            if (!alreadySeenSelfLoop.getAndSet(true)) {
              return edge;
            }
          } else {
            return edge;
          }
        }
        return endOfData();
      }
    };
  }

     * It's called both during normal shutdown and in error conditions.
     */
    private static void destroyContainer() {
        if (running.getAndSet(false)) {
            TimeoutManager.getInstance().stop();
            if (logger.isDebugEnabled()) {
                logger.debug("Destroying LaContainer...");
            }

     * cancelled before the callable started execution.
     */
    SettableFuture<@Nullable Void> newFuture = SettableFuture.create();

    ListenableFuture<@Nullable Void> oldFuture = ref.getAndSet(newFuture);

    // Invoke our task once the previous future completes.
    TrustedListenableFutureTask<T> taskFuture = TrustedListenableFutureTask.create(task);
    oldFuture.addListener(taskFuture, taskExecutor);

     * @param status The current cluster status.
     * @return true if the state has changed, false otherwise.
     */
    public boolean isChangedClusterState(final int status) {
        return previousClusterState.getAndSet(status) != status;
    }

    /**
     * Creates a new action validator.
     *
     * @param requestManager  The request manager.
     * @param messagesCreator The messages creator.