* asynchronous handling, message chaining, cancellation, and timeout management.
 *
 * @author mbechler
 */
public interface CommonServerMessageBlockRequest extends CommonServerMessageBlock, Request {

    /**
     * Checks if the request will be handled asynchronously.
     *
     * @return request was handled asynchronously
     */
    boolean isResponseAsync();

    /**
     *
     * @return next chained message
     */

      queue.add(submittedTask);
      workerRunningState = QUEUING;
    }

    try {
      executor.execute(worker);
    } catch (Throwable t) {
      // Any Exception is either a RuntimeException or sneaky checked exception.
      synchronized (queue) {
        boolean removed =
            (workerRunningState == IDLE || workerRunningState == QUEUING)
                && queue.removeLastOccurrence(submittedTask);

 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *
 * This is the same behavior as type-variable usages have to Kotlin and to the Checker Framework.
 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},

 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *
 * This is the same behavior as type-variable usages have to Kotlin and to the Checker Framework.
 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},

 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *
 * This is the same behavior as type-variable usages have to Kotlin and to the Checker Framework.
 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},

 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *
 * This is the same behavior as type-variable usages have to Kotlin and to the Checker Framework.
 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},

 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *
 * This is the same behavior as type-variable usages have to Kotlin and to the Checker Framework.
 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},

 *       String}.
 *   <li>{@code getElement} on a {@code Multiset.Entry<@Nullable String>} returns {@code @Nullable
 *       String}.
 * </ul>
 *
 * This is the same behavior as type-variable usages have to Kotlin and to the Checker Framework.
 * Contrast the method above to:
 *
 * <ul>
 *   <li>methods whose return type is a type variable but which can never return {@code null},

                }),
        (accum, t) -> {
          /*
           * We assign these to variables before calling checkNotNull to work around a bug in our
           * nullness checker.
           */
          K key = keyFunction.apply(t);
          V newValue = valueFunction.apply(t);
          accum.put(
              checkNotNull(key, "Null key for input %s", t),

      }
    }

    /*
     * TODO(cpovirk): `return (V) removedValue` once our checker permits that.
     *
     * (We promoted a class of warnings into errors because sometimes they indicate real problems.
     * But now we need to "undo" some instance of spurious errors, as discussed in
     * https://github.com/jspecify/checker-framework/issues/8.)
     */
    return removedValue == null ? null : (V) removedValue;
  }