* value can result in multiple misses, all returning the results of a single cache load
   * operation.
   */
  public long missCount() {
    return missCount;
  }

  /**
   * Returns the ratio of cache requests which were misses. This is defined as {@code missCount /

   * value can result in multiple misses, all returning the results of a single cache load
   * operation.
   */
  public long missCount() {
    return missCount;
  }

  /**
   * Returns the ratio of cache requests which were misses. This is defined as {@code missCount /

      int expectedSize) {
    return new CompactLinkedHashSet<>(expectedSize);
  }

  private static final int ENDPOINT = -2;

  // TODO(user): predecessors and successors should be collocated (reducing cache misses).
  // Might also explore collocating all of [hash, next, predecessor, successor] fields of an
  // entry in a *single* long[], though that reduces the maximum size of the set by a factor of 2

  /**

 * shared resources.
 *
 * @param <K> the most general type of keys this listener can listen for; for example {@code Object}
 *     if any key is acceptable
 * @param <V> the most general type of values this listener can listen for; for example {@code
 *     Object} if any key is acceptable
 * @author Charles Fry
 * @since 10.0
 */
@GwtCompatible
@FunctionalInterface

    /**
     * Helper class to traverse graph. Required to make the containing method thread-safe
     * and yet use class level data to lessen stack usage in recursion
     */
    private class ClasspathGraphVisitor {
        MetadataGraph graph;

        ClasspathContainer cpc;

        List<MetadataGraphVertex> visited;

  }

  ImmutableMap<K, V> getAllPresent(Iterable<?> keys) {
    int hits = 0;
    int misses = 0;

    ImmutableMap.Builder<K, V> result = ImmutableMap.builder();
    for (Object key : keys) {
      V value = get(key);
      if (value == null) {
        misses++;
      } else {
        // TODO(fry): store entry key instead of query key
        @SuppressWarnings("unchecked")

  }

  ImmutableMap<K, V> getAllPresent(Iterable<?> keys) {
    int hits = 0;
    int misses = 0;

    ImmutableMap.Builder<K, V> result = ImmutableMap.builder();
    for (Object key : keys) {
      V value = get(key);
      if (value == null) {
        misses++;
      } else {
        // TODO(fry): store entry key instead of query key
        @SuppressWarnings("unchecked")

        public String toString() {
          return "stopped()";
        }
      };

  /**
   * A listener for the aggregate state changes of the services that are under management. Users
   * that need to listen to more fine-grained events (such as when each particular {@linkplain
   * Service service} starts, or terminates), should attach {@linkplain Service.Listener service
   * listeners} to each individual service.
   *

     *
     * This callback is intended to allow extensions to perform cleanup of any
     * allocated external resources after the build. It is invoked on best-effort
     * basis and may be missed due to an Error or RuntimeException in Maven core
     * code.
     *
     * @param session the Maven session
     * @throws MavenExecutionException in case of issue
     * @since 3.2.1, MNG-5389
     */

 * shared resources.
 *
 * @param <K> the most general type of keys this listener can listen for; for example {@code Object}
 *     if any key is acceptable
 * @param <V> the most general type of values this listener can listen for; for example {@code
 *     Object} if any key is acceptable
 * @author Charles Fry
 * @since 10.0
 */
@GwtCompatible