if (entry == null) {
      throw new NoSuchElementException();
    } else {
      return entry.getKey();
    }
  }

  @Override
  @ParametricNullness
  public K lastKey() {
    Entry<K, V> entry = lastEntry();
    if (entry == null) {
      throw new NoSuchElementException();
    } else {
      return entry.getKey();
    }
  }

  @Override
  public @Nullable Entry<K, V> lowerEntry(@ParametricNullness K key) {

      return new WrappedSortedSet(
          getKey(),
          getSortedSetDelegate().headSet(toElement),
          (getAncestor() == null) ? this : getAncestor());
    }

    @Override
    public SortedSet<V> subSet(@ParametricNullness V fromElement, @ParametricNullness V toElement) {
      refreshIfEmpty();
      return new WrappedSortedSet(
          getKey(),

    }

    @Override
    public boolean matchesRequirements(Map<String, String> requirements) {
        for (Map.Entry<String, String> requirement : requirements.entrySet()) {
            String key = requirement.getKey();

            RequirementMatcher matcher = provides.get(key);

            if (matcher == null) {
                getLog().debug("Toolchain {} is missing required property: {}", this, key);
                return false;

                          return next.getValue();
                        }

                        @Override
                        public String getKey() {
                          return next.getKey();
                        }

                        @Override
                        public boolean equals(@Nullable Object obj) {
                          return next.equals(obj);

    public void remove() {
      checkRemove(lastReturned != null);
      MapMakerInternalMap.this.remove(lastReturned.getKey());
      lastReturned = null;
    }
  }

  final class KeyIterator extends HashIterator<K> {

    @Override
    public K next() {
      return nextEntry().getKey();
    }
  }

  final class ValueIterator extends HashIterator<V> {

    @Override

    Iterator<Entry<K, V>> iterator = multimap().entries().iterator();
    Entry<K, V> entry = iterator.next();
    K key = entry.getKey();
    V value = entry.getValue();
    multimap().removeAll(key);
    assertEquals(key, entry.getKey());
    assertEquals(value, entry.getValue());
  }

          }

          @Override
          public K next() {
            Entry<K, V> entry = entryIterator.next(); // store local reference for thread-safety
            cacheEntry = entry;
            return entry.getKey();
          }
        };
      }

      @Override
      public int size() {
        return backingMap.size();
      }

      @Override
      public boolean contains(@Nullable Object key) {

    super(key, value);
    checkEntryNotNull(key, value);
  }

  // Redeclare methods to make them `final`, just to be extra-safe.

  @Override
  @ParametricNullness
  public final K getKey() {
    return super.getKey();
  }

  @Override
  @ParametricNullness
  public final V getValue() {
    return super.getValue();
  }

  @Override
  @ParametricNullness

            Metadata metadata = it.next();
            if (metadata instanceof VersionsMetadata versionsMetadata) {
                it.remove();
                processedVersions.put(versionsMetadata.getKey(), versionsMetadata);
            }
        }
    }

    @Override
    public Collection<? extends Metadata> prepare(Collection<? extends Artifact> artifacts) {
        return Collections.emptyList();
    }

    Multimap<K, V> multimap = multimap();
    assertEquals(expectedSize, multimap.size());

    int size = 0;
    for (Entry<K, V> entry : multimap.entries()) {
      assertTrue(multimap.containsEntry(entry.getKey(), entry.getValue()));
      size++;
    }
    assertEquals(expectedSize, size);

    int size2 = 0;
    for (Entry<K, Collection<V>> entry2 : multimap.asMap().entrySet()) {
      size2 += entry2.getValue().size();