* implement Function<A, B>, as discussed in a class-level comment), it would make some sense to
     * perform runtime null checks on the input and output. (That would also make NullPointerTester
     * happy!) However, since we didn't do that for many years, we're not about to start now.
     * (Runtime checks could be particularly bad for users of LegacyConverter.)
     *

   * worker runs and exhausts the queue, another thread enqueues a task and fails to schedule the
   * worker, and then the first thread's call to delegate.execute() returns. Without this counter,
   * it would observe the QUEUING state and set it to QUEUED, and the worker would never be
   * scheduled again for future submissions.
   */
  @GuardedBy("queue")
  private long workerRunCount = 0;

  @RetainedWith private final QueueWorker worker = new QueueWorker();

     *
     * - Any kind of Error from a listener. Even if we could distinguish that case (by exposing some
     * extra state from AbstractFuture), our options are limited: A call to setException() would be
     * a no-op. We could log, but if that's what we really want, we should modify
     * AbstractFuture.executeListener to do so, since that method would have the ability to continue
     * to execute other listeners.
     *

    /*
     * requireNonNull is safe because this is called from the constructor after `futures` is set but
     * before releaseResources could be called (because we have not yet set up any of the listeners
     * that could call it, nor exposed this Future for users to call cancel() on).
     */
    requireNonNull(futures);

    // Corner case: List is empty.
    if (futures.isEmpty()) {
      handleAllCompleted();

     * hopefully could avoid implementing Entry or ValueSetLink at all. (But note that that approach
     * requires us to define extra classes -- unfortunate under Android.) *Then* we could consider
     * lying about the fields below on the grounds that we always initialize them just after the
     * constructor -- an example of the kind of lying that our hypothetical bytecode rewriter would

    expected.addAll(index, elements);
    expectContents(expected);
  }

  /*
   * TODO: if we're testing a list, we could check indexOf(). (Doing it in
   * AbstractListTester isn't enough because many tests that run on lists don't
   * extends AbstractListTester.) We could also iterate over all elements to
   * verify absence
   */
  protected void expectMissing(E... elements) {
    for (E element : elements) {

  LazyLogger(Class<?> ownerOfLogger) {
    this.loggerName = ownerOfLogger.getName();
  }

  Logger get() {
    /*
     * We use double-checked locking. We could the try racy single-check idiom, but that would
     * depend on Logger not contain mutable state.
     *
     * We could use Suppliers.memoizingSupplier here, but I micro-optimized to this implementation

   * AnnotatedElement}, which {@code TypeVariable} began to extend only in Java 8. Those methods
   * refer only to types present in Java 7, so we could implement them in {@code TypeVariableImpl}
   * today. (We could probably then make {@code TypeVariableImpl} implement {@code AnnotatedElement}
   * so that we get partial compile-time checking.)
   *

   * {@link PermittedMetaException} instances, which wrap a set of all exceptions that the iterator
   * could throw during the invocation of that method. This is necessary because, e.g., a call to
   * {@code iterator().remove()} of an unmodifiable list could throw either {@link
   * IllegalStateException} or {@link UnsupportedOperationException}. Note that iterator

   * Comparisons between the two should take this into account.
   *
   * <p>Fingerprint2011() is a form of Murmur2 on strings up to 32 bytes and a form of CityHash for
   * longer strings. It could have been one or the other throughout. The main advantage of the
   * combination is that CityHash has a bunch of special cases for short strings that don't need to
   * be replicated here. The result will never be 0 or 1.
   *