* java.util.stream.Stream#filter}. This method is not being deprecated, but we gently encourage
   * you to migrate to streams.
   */
  // TODO(kevinb): how to omit that last sentence when building GWT javadoc?
  public static <E extends @Nullable Object> Set<E> filter(
      Set<E> unfiltered, Predicate<? super E> predicate) {
    if (unfiltered instanceof SortedSet) {
      return filter((SortedSet<E>) unfiltered, predicate);

        }
        return parent;
    }

    private Map<String, Activation> getProfileActivations(Model model) {
        return model.getProfiles().stream()
                .filter(p -> p.getActivation() != null)
                .collect(Collectors.toMap(Profile::getId, Profile::getActivation));
    }

    private Model injectProfileActivations(Model model, Map<String, Activation> activations) {

            // which may cause some re-entrance in the build() method and can
            // actually cause deadlocks.  In order to workaround the problem,
            // we do a first pass by reading all rawModels in order.
            List<ProjectBuildingResult> results = new ArrayList<>();
            boolean failure = false;
            for (InterimResult r : interimResults) {

   * underlying multimap.
   *
   * <p>The returned multimap isn't threadsafe or serializable, even if {@code unfiltered} is.
   *
   * <p>Many of the filtered multimap's methods, such as {@code size()}, iterate across every
   * key/value mapping in the underlying multimap and determine which satisfy the filter. When a

    Iterator<String> filtered = Iterators.filter(unfiltered, Predicates.alwaysFalse());
    List<String> expected = Collections.emptyList();
    List<String> actual = Lists.newArrayList(filtered);
    assertEquals(expected, actual);
  }

  public void testFilterMatchAll() {
    Iterator<String> unfiltered = Lists.newArrayList("foo", "bar").iterator();
    Iterator<String> filtered = Iterators.filter(unfiltered, Predicates.alwaysTrue());

                    Version.V20,
                    "modelVersion",
                    null,
                    "of '" + string + "' is older than the versions supported by this version of Maven: "
                            + validVersions + ". Building this project requires an older version of Maven.",
                    tracker);

        } else {
            addViolation(
                    problems,