* convenient.
   *
   * <p>By default, a {@code Builder} will generate bimaps that iterate over entries in the order
   * they were inserted into the builder. For example, in the above example, {@code
   * WORD_TO_INT.entrySet()} is guaranteed to iterate over the entries in the order {@code "one"=1,
   * "two"=2, "three"=3}, and {@code keySet()} and {@code values()} respect the same order. If you

    throw new AssertionError("should never be called");
  }

  @Override
  public ImmutableCollection<V> values() {
    return (ImmutableCollection<V>) super.values();
  }

  @Override
  abstract ImmutableCollection<V> createValues();

  @Override
  final Iterator<V> valuesIterator() {
    throw new AssertionError("should never be called");
  }

  /**
   * {@inheritDoc}

     *
     * @param project {@link Project} or {@code null}.
     * @return the effective properties, never {@code null}
     */
    @Nonnull
    Map<String, String> getEffectiveProperties(@Nullable Project project);

    /**
     * Returns the current maven version
     * @return the maven version, never {@code null}
     */
    @Nonnull
    Version getMavenVersion();

    int getDegreeOfConcurrency();

  }

  /**
   * Returns an unmodifiable <b>view</b> of the union of two sets. The returned set contains all
   * elements that are contained in either backing set. Iterating over the returned set iterates
   * first over all the elements of {@code set1}, then over each element of {@code set2}, in order,
   * that is not contained in {@code set1}.
   *
   * <p>Results are undefined if {@code set1} and {@code set2} are sets based on different

        // have a model that is suitable, yet more checks are done here and the one for the version is problematic
        // before because with parents as ranges it will never work in this scenario.
        //

        String groupId = getGroupId(candidateModel);
        String artifactId = candidateModel.getArtifactId();

        if (groupId == null

    @Override
    Set<E> createElementSet() {
      return Sets.filter(unfiltered.elementSet(), predicate);
    }

    @Override
    Iterator<E> elementIterator() {
      throw new AssertionError("should never be called");
    }

    @Override
    Set<Entry<E>> createEntrySet() {
      return Sets.filter(
          unfiltered.entrySet(),
          new Predicate<Entry<E>>() {
            @Override

import java.util.stream.Collector;
import java.util.stream.Stream;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link SetMultimap} whose contents will never change, with many other important properties
 * detailed at {@link ImmutableCollection}.
 *
 * <p><b>Warning:</b> As in all {@link SetMultimap}s, do not modify either a key <i>or a value</i>

import java.util.SortedSet;
import java.util.stream.Collector;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link NavigableSet} whose contents will never change, with many other important properties
 * detailed at {@link ImmutableCollection}.
 *
 * <p><b>Warning:</b> as with any sorted collection, you are strongly advised not to use a {@link

import java.util.stream.Collector;
import java.util.stream.Collectors;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A {@link NavigableMap} whose contents will never change, with many other important properties
 * detailed at {@link ImmutableCollection}.
 *
 * <p><b>Warning:</b> as with any sorted collection, you are strongly advised not to use a {@link

   * reached, but not the other, the shorter iterable is considered to be less than the longer one.
   * For example, a lexicographical natural ordering over integers considers {@code [] < [1] < [1,
   * 1] < [1, 2] < [2]}.
   *
   * <p>Note that {@code Collections.reverseOrder(lexicographical(comparator))} is not equivalent to