ImmutableSet<Entry<K, V>> result = entries;
    return result == null ? (entries = new EntrySet<>(this)) : result;
  }

  private static final class EntrySet<K, V> extends ImmutableSet<Entry<K, V>> {
    @Weak private final transient ImmutableSetMultimap<K, V> multimap;

    EntrySet(ImmutableSetMultimap<K, V> multimap) {
      this.multimap = multimap;
    }

    @Override

    } catch (RuntimeException tolerated) {
      // GWT's TreeMap.entrySet().removeAll(null) doesn't throws NPE.
    }
  }

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

  @Override

    assertFalse(getMap().entrySet().iterator().hasNext());
  }

  @MapFeature.Require({FAILS_FAST_ON_CONCURRENT_MODIFICATION, SUPPORTS_REMOVE})
  @CollectionSize.Require(SEVERAL)
  public void testClearConcurrentWithEntrySetIteration() {
    assertThrows(
        ConcurrentModificationException.class,
        () -> {
          Iterator<Entry<K, V>> iterator = getMap().entrySet().iterator();
          getMap().clear();

        return CollectSpliterators.map(submap.entrySet().spliterator(), AsMap.this::wrapEntry);
      }

      // The following methods are included for performance.

      @Override
      public boolean contains(@Nullable Object o) {
        return Collections2.safeContains(submap.entrySet(), o);
      }

      @Override
      public boolean remove(@Nullable Object o) {

  @CollectionSize.Require(SEVERAL)
  public void testPollFirst() {
    assertEquals(a, navigableMap.pollFirstEntry());
    assertEquals(entries.subList(1, entries.size()), copyToList(navigableMap.entrySet()));
  }

  @MapFeature.Require(absent = SUPPORTS_REMOVE)
  public void testPollFirstUnsupported() {
    assertThrows(UnsupportedOperationException.class, () -> navigableMap.pollFirstEntry());
  }

  @CollectionSize.Require(SEVERAL)
  public void testPollFirst() {
    assertEquals(a, navigableMap.pollFirstEntry());
    assertEquals(entries.subList(1, entries.size()), copyToList(navigableMap.entrySet()));
  }

  @MapFeature.Require(absent = SUPPORTS_REMOVE)
  public void testPollFirstUnsupported() {
    assertThrows(UnsupportedOperationException.class, () -> navigableMap.pollFirstEntry());
  }

    List<Entry<V, K>> reversedEntries = new ArrayList<>();
    for (Entry<K, V> entry : expected) {
      reversedEntries.add(reverseEntry(entry));
    }
    assertEqualIgnoringOrder(getMap().inverse().entrySet(), reversedEntries);

    for (Entry<K, V> entry : expected) {
      assertEquals(
          "Wrong key for value " + entry.getValue(),
          entry.getKey(),
          getMap().inverse().get(entry.getValue()));

    }

    public static <K, T extends Map<K, Artifact>> T copyArtifacts(Map<K, ? extends Artifact> from, T to) {
        if (from != null) {
            for (Map.Entry<K, ? extends Artifact> entry : from.entrySet()) {
                to.put(entry.getKey(), ArtifactUtils.copyArtifact(entry.getValue()));
            }
        }

        return to;
    }

    private static <T> List<T> copyList(List<T> original) {

        try {
            // feature
            for (final Map.Entry<String, String> entry : featureMap.entrySet()) {
                parser.setFeature(entry.getKey(), "true".equalsIgnoreCase(entry.getValue()));
            }

            // property
            for (final Map.Entry<String, String> entry : propertyMap.entrySet()) {
                parser.setProperty(entry.getKey(), entry.getValue());
            }

            return removeEntryIf(compose(not(in(c)), Maps.<Range<K>>keyFunction()));
          }
        };
      }

      @Override
      public Set<Entry<Range<K>, V>> entrySet() {
        return new Maps.EntrySet<Range<K>, V>() {
          @Override
          Map<Range<K>, V> map() {
            return SubRangeMapAsMap.this;
          }

          @Override