// and when it is done will run the listeners.
      if (hasListeners.compareAndSet(false, true)) {
        if (delegate.isDone()) {
          // If the delegate is already done, run the execution list immediately on the current
          // thread.
          executionList.execute();
          return;
        }

        // TODO(lukes): handle RejectedExecutionException
        adapterExecutor.execute(

  }

  /**
   * Creates and returns a new builder, configured to build {@code MinMaxPriorityQueue} instances
   * that are limited to {@code maximumSize} elements. Each time a queue grows beyond this bound, it
   * immediately removes its greatest element (according to its comparator), which might be the
   * element that was just added.
   */
  @SuppressWarnings("rawtypes") // https://github.com/google/guava/issues/989

   * executor. Each event can be added and dispatched as separate phases.
   *
   * <p>This class is very similar to {@link SequentialExecutor} with the exception that events can
   * be added without necessarily executing immediately.
   */
  private static final class PerListenerQueue<L> implements Runnable {
    final L listener;
    final Executor executor;

    @GuardedBy("this")

personally. The committee will then review the incident, follow up with any additional questions,
and make a decision as to how to respond.

Anyone asked to stop unacceptable behavior is expected to comply immediately. If an individual
engages in unacceptable behavior, the Square Code of Conduct committee may take any action they deem
appropriate, up to and including a permanent ban from all of Square spaces without warning.

   *
   * <p>The returned executor is backed by the executor returned by {@link
   * MoreExecutors#newDirectExecutorService} and subject to the same constraints.
   *
   * <p>Although all tasks are immediately executed in the thread that submitted the task, this
   * {@code ExecutorService} imposes a small locking overhead on each task submission in order to
   * implement shutdown and termination behavior.
   *

 * this implementation type, ie. no hint/name.
 *
 * This leads to a second side effect in that any @Inject request for just ModelProcessor in
 * the same injector is immediately matched to this explicit binding, which means extensions
 * cannot override this binding. This is because the lookup is always short-circuited in this

    RateLimiter limiter = RateLimiter.create(5.0, stopwatch);
    limiter.acquire(); // R0.00
    stopwatch.sleepMillis(200); // U0.20, we are ready for the next request...
    limiter.acquire(); // R0.00, ...which is granted immediately
    limiter.acquire(); // R0.20
    assertEvents("R0.00", "U0.20", "R0.00", "R0.20");
  }

  public void testSimpleAcquireReturnValues() {
    RateLimiter limiter = RateLimiter.create(5.0, stopwatch);

    RateLimiter limiter = RateLimiter.create(5.0, stopwatch);
    limiter.acquire(); // R0.00
    stopwatch.sleepMillis(200); // U0.20, we are ready for the next request...
    limiter.acquire(); // R0.00, ...which is granted immediately
    limiter.acquire(); // R0.20
    assertEvents("R0.00", "U0.20", "R0.00", "R0.20");
  }

  public void testSimpleAcquireReturnValues() {
    RateLimiter limiter = RateLimiter.create(5.0, stopwatch);

            // If this CAS succeeds, we know that the provided callable will never be invoked,
            // so when oldFuture completes it is safe to allow the next submitted task to
            // proceed. Doing this immediately here lets the next task run without waiting for
            // the cancelled task's executor to run the noop AsyncCallable.
            //
            // ---
            //

  }

  /**
   * Returns a {@code ListenableFuture} which has an exception set immediately upon construction.
   *
   * <p>The returned {@code Future} can't be cancelled, and its {@code isDone()} method always
   * returns {@code true}. Calling {@code get()} will immediately throw the provided {@code
   * Throwable} wrapped in an {@code ExecutionException}.
   */