RateLimiter limiter = RateLimiter.create(2.0, 4000, MILLISECONDS, 3.0, stopwatch);
    for (int i = 0; i < 8; i++) {
      limiter.acquire(); // // #1
    }
    stopwatch.sleepMillis(4500); // #2: back to cold state (warmup period + repay last acquire)
    for (int i = 0; i < 3; i++) { // only three steps, we're somewhere in the warmup period
      limiter.acquire(); // #3
    }

import java.util.Map;

/**
 * A dummy superclass to support GWT serialization of the element types of a {@link HashMultimap}.
 * The GWT supersource for this class contains a field for each type.
 *
 * <p>For details about this hack, see {@code GwtSerializationDependencies}, which takes the same
 * approach but with a subclass rather than a superclass.
 *
 * <p>TODO(cpovirk): Consider applying this subclass approach to our other types.
 */

  }

  /*
   * TODO(b/242884182): Figure out why this helps produce the same class file when we compile most
   * of common.collect a second time with the results of the first compilation on the classpath. Or
   * just back this out once we stop doing that (which we'll do after our internal GWT setup
   * changes).
   */
  @Override
  public ImmutableMap<Object, Collection<Object>> asMap() {
    return super.asMap();
  }

/**
 * A dummy superclass to support GWT serialization of the element type of an {@link
 * ImmutableMultiset}. The GWT supersource for this class contains a field of type {@code E}.
 *
 * <p>For details about this hack, see {@code GwtSerializationDependencies}, which takes the same
 * approach but with a subclass rather than a superclass.
 *
 * <p>TODO(cpovirk): Consider applying this subclass approach to our other types.
 *

  }

  /**
   * Provides a lexicographical comparator implementation; either a Java implementation or a faster
   * implementation based on {@link Unsafe}.
   *
   * <p>Uses reflection to gracefully fall back to the Java implementation if {@code Unsafe} isn't
   * available.
   */
  @VisibleForTesting
  static class LexicographicalComparatorHolder {
    static final String UNSAFE_COMPARATOR_NAME =

     * creator of the problem, the general expectation is that the hint provides sufficient information to the user to
     * track the problem back to its origin. A concrete example for such a source hint can be the file path or URL from
     * which the settings were read.
     *

          horizon.removeFirst();
          return null;
        }
      };
    }

    final Iterator<N> breadthFirst(Iterator<? extends N> startNodes) {
      return topDown(startNodes, InsertionOrder.BACK);
    }

    final Iterator<N> preOrder(Iterator<? extends N> startNodes) {
      return topDown(startNodes, InsertionOrder.FRONT);
    }

    /**

  /**
   * Returns an optional enum constant for the given type, using {@link Enum#valueOf}. If the
   * constant does not exist, {@link Optional#absent} is returned. A common use case is for parsing
   * user input or falling back to a default enum constant. For example, {@code
   * Enums.getIfPresent(Country.class, countryInput).or(Country.DEFAULT);}
   *
   * @since 12.0
   */

 *       {@code NullPointerTester} would need are not available) and in case of <a
 *       href="https://bugs.openjdk.java.net/browse/JDK-8202469">JDK-8202469</a>
 * </ul>
 *
 * <p>This annotation is a temporary hack. We will remove it after we're able to adopt the <a
 * href="https://jspecify.dev/">JSpecify</a> nullness annotations and <a
 * href="https://github.com/google/guava/issues/6126#issuecomment-1203145963">tools no longer need
 * it</a>.

 *       {@code NullPointerTester} would need are not available) and in case of <a
 *       href="https://bugs.openjdk.java.net/browse/JDK-8202469">JDK-8202469</a>
 * </ul>
 *
 * <p>This annotation is a temporary hack. We will remove it after we're able to adopt the <a
 * href="https://jspecify.dev/">JSpecify</a> nullness annotations and <a
 * href="https://github.com/google/guava/issues/6126#issuecomment-1203145963">tools no longer need
 * it</a>.