* decide not to by returning -1L.
 *
 * Task Queues
 * -----------
 *
 * Tasks are bound to the [TaskQueue] they are scheduled in. Each queue is sequential and the tasks
 * within it never execute concurrently. It is an error to use a task in multiple queues.
 */
abstract class Task(
  val name: String,
  val cancelable: Boolean = true,
) {

Ahora, veamos cómo puedes usarlo para devolver una respuesta personalizada.

Digamos que quieres devolver una respuesta <a href="https://en.wikipedia.org/wiki/XML" class="external-link" target="_blank">XML</a>.

Podrías poner tu contenido XML en un string, ponerlo en una `Response` y devolverlo:

```Python hl_lines="1  18"

  repeated PriorityLevelConfigurationCondition conditions = 1;
}

// QueuingConfiguration holds the configuration parameters for queuing
message QueuingConfiguration {
  // `queues` is the number of queues for this priority level. The
  // queues exist independently at each apiserver. The value must be
  // positive.  Setting it to 1 effectively precludes
  // shufflesharding and thus makes the distinguisher method of

  repeated PriorityLevelConfigurationCondition conditions = 1;
}

// QueuingConfiguration holds the configuration parameters for queuing
message QueuingConfiguration {
  // `queues` is the number of queues for this priority level. The
  // queues exist independently at each apiserver. The value must be
  // positive.  Setting it to 1 effectively precludes
  // shufflesharding and thus makes the distinguisher method of

 * the License.
 */

package com.google.common.eventbus;

import static com.google.common.base.Preconditions.checkNotNull;
import static java.util.Objects.requireNonNull;

import com.google.common.collect.Queues;
import java.util.Iterator;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;

/**
 * Handler for dispatching events to subscribers, providing different event ordering guarantees that

  repeated PriorityLevelConfigurationCondition conditions = 1;
}

// QueuingConfiguration holds the configuration parameters for queuing
message QueuingConfiguration {
  // `queues` is the number of queues for this priority level. The
  // queues exist independently at each apiserver. The value must be
  // positive.  Setting it to 1 effectively precludes
  // shufflesharding and thus makes the distinguisher method of

 * limitations under the License.
 */

package com.google.common.eventbus;

import static com.google.common.truth.Truth.assertThat;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Queues;
import com.google.common.util.concurrent.Uninterruptibles;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.CyclicBarrier;

Ten en cuenta que se pueden añadir headers propietarios personalizados <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">usando el prefijo 'X-'</a>.

import static com.google.common.util.concurrent.Futures.immediateFuture;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Queues;
import com.google.common.util.concurrent.ListenableFuture;
import java.util.Deque;
import java.util.Map;
import java.util.concurrent.Executor;
import java.util.concurrent.Future;

    final L listener;
    final Executor executor;

    @GuardedBy("this")
    final Queue<ListenerCallQueue.Event<L>> waitQueue = Queues.newArrayDeque();

    @GuardedBy("this")
    final Queue<Object> labelQueue = Queues.newArrayDeque();

    @GuardedBy("this")
    boolean isThreadScheduled;

    PerListenerQueue(L listener, Executor executor) {