@Override
  protected void tearDown() throws Exception {

    // Make sure we have no waiting threads.
    latch.countDown();
  }

  /** Constructs a listenable future with a value available after the latch has counted down. */
  protected abstract <V> ListenableFuture<V> createListenableFuture(
      V value, @Nullable Exception except, CountDownLatch waitOn);

{* ../../docs_src/advanced_middleware/tutorial001.py hl[2,6] *}

## `TrustedHostMiddleware`

Garante que todas as requisições recebidas tenham um cabeçalho `Host` corretamente configurado, a fim de proteger contra ataques de cabeçalho de host HTTP.

{* ../../docs_src/advanced_middleware/tutorial002.py hl[2,6:8] *}

Os seguintes argumentos são suportados:

   * exception is thrown, this exception is used as the result of the output {@code Future}.
   *
   * <p>Usage example:
   *
   * <pre>{@code
   * // Falling back to a zero counter in case an exception happens when processing the RPC to fetch
   * // counters.
   * ListenableFuture<Integer> faultTolerantFuture =
   *     fetchCounters().catching(FetchException.class, x -> 0, directExecutor());
   * }</pre>
   *

	listener      *httpListener // HTTP listener for all 'Addrs' field.
	inShutdown    uint32        // indicates whether the server is in shutdown or not
	requestCount  int32         // counter holds no. of request in progress.
}

// GetRequestCount - returns number of request in progress.
func (srv *Server) GetRequestCount() int {
	return int(atomic.LoadInt32(&srv.requestCount))
}

/**
 * A helper which does some thread-safe operations for aggregate futures, which must be implemented
 * differently in GWT. Namely:
 *
 * <ul>
 *   <li>Lazily initializes a set of seen exceptions
 *   <li>Decrements a counter atomically
 * </ul>
 */
@GwtCompatible(emulated = true)
@ReflectionSupport(value = ReflectionSupport.Level.FULL)
@ElementTypesAreNonnullByDefault
abstract class AggregateFutureState<OutputT extends @Nullable Object>

     compliant prior to 30 days after Your receipt of the notice.

5.2. If You initiate litigation against any entity by asserting a patent
     infringement claim (excluding declaratory judgment actions, counter-claims,
     and cross-claims) alleging that a Contributor Version directly or
     indirectly infringes any patent, then the rights granted to You by any and

  @Override
  protected void tearDown() throws Exception {

    // Make sure we have no waiting threads.
    latch.countDown();
  }

  /** Constructs a listenable future with a value available after the latch has counted down. */
  protected abstract <V> ListenableFuture<V> createListenableFuture(
      V value, @Nullable Exception except, CountDownLatch waitOn);

        .build(),
    )
    val asyncRequestBody: RequestBody =
      object : RequestBody() {
        var counter = 0

        override fun contentType() = null

        override fun writeTo(sink: BufferedSink) {
          counter++
          assertThat(counter).isLessThanOrEqualTo(1)
          sink.writeUtf8("Hello request!")
          sink.close()
        }

        private final DirContext context;

        private int counter = 1;

        protected DirContextHolder(final DirContext context) {
            this.context = context;
        }

        public DirContext get() {
            return context;
        }

        public void inc() {
            counter++;
        }

        @Override
        public void close() {

	if objectAPI == nil {
		return
	}

	vars := mux.Vars(r)
	count, err := strconv.Atoi(vars["count"])
	if err != nil {
		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, err), r.URL)
		return
	}

	chEntries, err := listServerConfigHistory(ctx, objectAPI, true, count)
	if err != nil {
		writeErrorResponseJSON(ctx, w, toAdminAPIErr(ctx, err), r.URL)
		return
	}