final Map<String, List<String>> frontMatter = visitor.getData();
        for (final Map.Entry<String, List<String>> entry : frontMatter.entrySet()) {
            final String key = "frontmatter." + entry.getKey();
            final List<String> values = entry.getValue();
            if (values != null && !values.isEmpty()) {
                extractData.putValues(key, values.toArray(new String[0]));
            }
        }

    ImmutableMultiset.Builder<T> builder = ImmutableMultiset.builder();
    for (Entry<T, Integer> entry : counts.entrySet()) {
      builder.addCopies(entry.getKey(), entry.getValue());
    }
    return builder.build();
  }

  private ListenerCallQueue.Event<Object> countDownEvent(CountDownLatch latch) {
    return new ListenerCallQueue.Event<Object>() {
      @Override

    ImmutableMultiset.Builder<T> builder = ImmutableMultiset.builder();
    for (Entry<T, Integer> entry : counts.entrySet()) {
      builder.addCopies(entry.getKey(), entry.getValue());
    }
    return builder.build();
  }

  private ListenerCallQueue.Event<Object> countDownEvent(CountDownLatch latch) {
    return new ListenerCallQueue.Event<Object>() {
      @Override

                .collect(Collectors.groupingBy(Function.identity(), Collectors.counting()))
                .entrySet()
                .stream()
                .filter(p -> p.getValue() > 1)
                .map(Map.Entry::getKey)
                .collect(Collectors.toSet());

        // schedule independent projects (ordered by critical path priority)
        for (MavenProject mavenProject : analyzer.getRootSchedulableBuilds()) {

                        ImmutableClassToInstanceMap.builder();
                    for (Object object : elements) {
                      Entry<?, ?> entry = (Entry<?, ?>) object;
                      builder.put((Class) entry.getKey(), (Impl) entry.getValue());
                    }
                    return (Map) builder.build();
                  }
                })
            .named("ImmutableClassToInstanceMap")
            .withFeatures(

        // Extract artifact from all POMs in the project
        for (Map.Entry<Path, Document> entry : pomMap.entrySet()) {
            Path pomPath = entry.getKey();
            Document pomDocument = entry.getValue();

            Coordinates coordinate =
                    AbstractUpgradeStrategy.extractArtifactCoordinatesWithParentResolution(context, pomDocument);

            final StatsObject data = e.getValue();
            final Long begin = data.remove(BEGIN_KEY);
            if (begin != null) {
                printStats(e.getKey(), data, begin, false);
            }
        });

    }

    /**
     * Begins statistics tracking for the specified crawler object.
     * Creates a new statistics object in the cache and starts timing.

        this.releases = releases;
    }

    @Override
    public ArtifactRepositoryPolicy getReleases() {
        return releases;
    }

    @Override
    public String getKey() {
        return getId();
    }

    @Override
    public boolean isBlacklisted() {
        return blacklisted;
    }

    @Override
    public void setBlacklisted(boolean blacklisted) {

        @SuppressWarnings("rawtypes") // using raw types to avoid a bug in our nullness checker :(
        InternalEntry entry = map.getEntry(sample);
        if (entry != null) {
          Object canonical = entry.getKey();
          if (canonical != null) { // only matters if weak/soft keys are used
            // The compiler would know this is safe if not for our use of raw types (see above).
            @SuppressWarnings("unchecked")

  }

  private void putAll(Iterable<Entry<K, V>> entries) {
    Map<K, V> map = new LinkedHashMap<>();
    for (Entry<K, V> entry : entries) {
      map.put(entry.getKey(), entry.getValue());
    }
    getMap().putAll(map);
  }

  /**
   * Returns the {@link Method} instance for {@link #testPutAll_nullKeyUnsupported()} so that tests