protected Set<String> create(String[] elements) {
                    Set<String> difference = newHashSet(elements);
                    Set<String> set = newHashSet(samples());
                    set.addAll(difference);
                    Set<String> subset = newHashSet(samples());
                    subset.removeAll(difference);
                    return difference(set, subset);
                  }
                })

            @Override
            public BulkResponse addAll(final String index, final List<Map<String, Object>> docList,
                    final BiConsumer<Map<String, Object>, IndexRequestBuilder> options) {
                sentIndex.set(index);
                docList.forEach(x -> options.accept(x, new IndexRequestBuilder(this, IndexAction.INSTANCE)));
                sentDocList.addAll(docList);

    return result;
  }

  /*
   * a "type A" unmodifiable collection freaks out proactively, even if there
   * wasn't going to be any actual work to do anyway
   */

  @Override
  public boolean addAll(Collection<? extends E> elementsToAdd) {
    throw up();
  }

  @Override
  public boolean removeAll(Collection<?> elementsToRemove) {
    throw up();
  }

  @Override

                    firstItems.add(item);
                } else {
                    secondItems.add(item);
                }
            }
        }
        firstWords.addAll(secondWords);
        firstItems.addAll(secondItems);
        return new SuggestResponse(index, searchResponse.getTook().getMillis(), firstWords, searchResponse.getHits().getTotalHits().value(),
                firstItems);
    }

    /**

        (TestSortedMapGenerator<K, V>) parentBuilder.getSubjectGenerator().getInnerGenerator();

    List<Feature<?>> features = new ArrayList<>();
    features.add(NoRecurse.SUBMAP);
    features.addAll(parentBuilder.getFeatures());

    return newBuilderUsing(delegate, to, from)
        .named(parentBuilder.getName() + " subMap " + from + "-" + to)
        .withFeatures(features)

    }
  }

  public static class BuilderAddAllListGenerator extends TestStringListGenerator {
    @Override
    protected List<String> create(String[] elements) {
      return ImmutableList.<String>builder().addAll(asList(elements)).build();
    }
  }

  public static class BuilderReversedListGenerator extends TestStringListGenerator {
    @Override
    protected List<String> create(String[] elements) {

                FileUtils.listFiles(new File(baseDir, "images"), fessConfig.getSupportedUploadedMediaExtentionsAsArray(), true));
        fileList.addAll(FileUtils.listFiles(new File(baseDir, "css"), fessConfig.getSupportedUploadedCssExtentionsAsArray(), true));
        fileList.addAll(FileUtils.listFiles(new File(baseDir, "js"), fessConfig.getSupportedUploadedJsExtentionsAsArray(), true));
        return fileList;
    }

     * Add child URLs.
     * @param c the collection of request data to add to the child URL set
     */
    public void addAllUrl(final Collection<RequestData> c) {
        if (c != null) {
            childUrlSet.addAll(c);
        }
    }

    /**
     * Remove a child URL.
     * @param url the request data to remove from the child URL set
     */
    public void removeUrl(final RequestData url) {

    public int hashCode() {
      return standardHashCode();
    }

    @Override
    public boolean add(E element) {
      return standardAdd(element);
    }

    @Override
    public boolean addAll(Collection<? extends E> collection) {
      return standardAddAll(collection);
    }

    @Override
    public void clear() {
      standardClear();
    }

    @Override

    assertTrue(multimap().containsEntry(k0(), v3()));
  }

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPropagatesAddAllToMultimap() {
    Collection<V> result = multimap().get(k0());
    assertTrue(result.addAll(singletonList(v3())));
    assertTrue(multimap().containsKey(k0()));
    assertEquals(getNumElements() + 1, multimap().size());
    assertTrue(multimap().containsEntry(k0(), v3()));
  }