public int size() {
      assertTrue(Thread.holdsLock(mutex));
      return super.size();
    }

    @Override
    public boolean isEmpty() {
      assertTrue(Thread.holdsLock(mutex));
      return super.isEmpty();
    }

    @Override
    public @Nullable V remove(Object object) {
      assertTrue(Thread.holdsLock(mutex));
      return super.remove(object);
    }

    @Override
    public void clear() {

  static <E extends Comparable<? super E>>
      Collector<Range<E>, ?, ImmutableRangeSet<E>> toImmutableRangeSet() {
    return (Collector) TO_IMMUTABLE_RANGE_SET;
  }

  // Multisets

  static <T extends @Nullable Object, E> Collector<T, ?, ImmutableMultiset<E>> toImmutableMultiset(
      Function<? super T, ? extends E> elementFunction, ToIntFunction<? super T> countFunction) {
    checkNotNull(elementFunction);

        super(message, cause);

        this.project = project;
        pluginGroupId = plugin.getGroupId();
        pluginArtifactId = plugin.getArtifactId();
        pluginVersion = plugin.getVersion();
    }

    public PluginManagerException(Plugin plugin, String message, Throwable cause) {
        super(message, cause);

        pluginGroupId = plugin.getGroupId();

  @Override
  public void testEntrySetRemoveAllNullFromEmpty() {
    try {
      super.testEntrySetRemoveAllNullFromEmpty();
    } catch (RuntimeException tolerated) {
      // GWT's HashMap.entrySet().removeAll(null) doesn't throws NPE.
    }
  }

  @Override
  public void testEntrySetRetainAllNullFromEmpty() {
    try {
      super.testEntrySetRetainAllNullFromEmpty();
    } catch (RuntimeException tolerated) {

    }
    return resolver;
  }

  private TypeToken<? super T> getSupertypeFromUpperBounds(
      Class<? super T> supertype, Type[] upperBounds) {
    for (Type upperBound : upperBounds) {
      @SuppressWarnings("unchecked") // T's upperbound is <? super T>.
      TypeToken<? super T> bound = (TypeToken<? super T>) of(upperBound);
      if (bound.isSubtypeOf(supertype)) {

    /**
     * The cached super POM, lazily created.
     */
    private static final Map<String, Model> SUPER_MODELS = new ConcurrentHashMap<>();

    @Inject
    public DefaultSuperPomProvider(ModelProcessor modelProcessor) {
        this.modelProcessor = modelProcessor;
    }

    @Override
    public Model getSuperPom(String version) {

      assertTrue(Thread.holdsLock(mutex));
      return super.toString();
    }

    @Override
    public boolean equals(@Nullable Object o) {
      assertTrue(Thread.holdsLock(mutex));
      return super.equals(o);
    }

    @Override
    public int hashCode() {
      assertTrue(Thread.holdsLock(mutex));
      return super.hashCode();
    }

    @Override
    public boolean add(@Nullable E o) {

        super(message, artifact);
    }

    public ArtifactResolutionException(String message, Artifact artifact, List<ArtifactRepository> remoteRepositories) {
        super(message, artifact, remoteRepositories);
    }

    public ArtifactResolutionException(String message, Artifact artifact, Throwable cause) {
        super(message, artifact, null, cause);
    }

    @Override
    Builder<K, V> combine(ImmutableMultimap.Builder<K, V> other) {
      super.combine(other);
      return this;
    }

    /**
     * {@inheritDoc}
     *
     * @since 8.0
     */
    @CanIgnoreReturnValue
    @Override
    public Builder<K, V> orderKeysBy(Comparator<? super K> keyComparator) {
      super.orderKeysBy(keyComparator);
      return this;
    }

    /**

      implements SortedSet<E> {
    SynchronizedSortedSet(SortedSet<E> delegate, @CheckForNull Object mutex) {
      super(delegate, mutex);
    }

    @Override
    SortedSet<E> delegate() {
      return (SortedSet<E>) super.delegate();
    }

    @Override
    @CheckForNull
    public Comparator<? super E> comparator() {
      synchronized (mutex) {
        return delegate().comparator();
      }
    }