"Should not contain null after unsupported putIfAbsent(present, null)");
  }

  @CanIgnoreReturnValue
  private V putIfAbsent(Entry<K, V> entry) {
    return getMap().putIfAbsent(entry.getKey(), entry.getValue());
  }

    switch (map.size()) {
      case 0:
        return ImmutableMap.of();
      case 1:
        Entry<K, V> entry = getOnlyElement(map.entrySet());
        return ImmutableMap.of(entry.getKey(), entry.getValue());
      default:
        return new ImmutableEnumMap<>(map);
    }
  }

  private final transient EnumMap<K, V> delegate;

  private ImmutableEnumMap(EnumMap<K, V> delegate) {
    this.delegate = delegate;

        try {
            List<String> list;
            csvReader.readValues(); // ignore header
            while ((list = csvReader.readValues()) != null) {
                String targetWord = getValue(list, 0);
                if (StringUtil.isBlank(targetWord)) {
                    // skip
                    continue;
                }
                try {
                    boolean isDelete = false;

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

            @Override
            public ImmutableSet<V> getValue() {
              return ImmutableSet.of(backingEntry.getValue());
            }
          };
        }
      };
    }

    // redeclare to help optimizers with b/310253115
    @SuppressWarnings("RedundantOverride")

            result.setAttributes(source.entrySet()
                    .stream()
                    .filter(e -> !"name".equals(e.getKey()))
                    .map(e -> new Pair<>(e.getKey(), (String) e.getValue()))
                    .collect(Collectors.toMap(Pair::getFirst, Pair::getSecond)));
            return result;
        } catch (InstantiationException | IllegalAccessException e) {

  protected void assertMoreInvariants(Map<K, V> map) {
    // TODO: can these be moved to MapInterfaceTest?
    for (Entry<K, V> entry : map.entrySet()) {
      assertThat(entry.toString()).isEqualTo(entry.getKey() + "=" + entry.getValue());
    }

    assertThat(map.toString()).isEqualTo("{" + JOINER.join(map.entrySet()) + "}");
    assertThat(map.entrySet().toString()).isEqualTo("[" + JOINER.join(map.entrySet()) + "]");

            visitor.onStartHtmlElement(name);
            for (Map.Entry<String, String> entry : attributes.entrySet()) {
                visitor.onHtmlElementAttribute(entry.getKey(), entry.getValue());
            }
            attributes.clear();
            visitor.onStartHtmlElementComplete(name);
        }

        @Override
        public void onEndHtmlElement(String name) {

            final String key = e.getKey();
            String value = e.getValue();
            for (final Map.Entry<String, String> entry : paramEnvMap.entrySet()) {
                value = value.replace("${" + entry.getKey() + "}", entry.getValue());
            }
            return new Pair<>(key, value);

            headers.entrySet().stream().filter(e -> e.getKey() != null).forEach(
                    e -> map.put(e.getKey().toLowerCase(Locale.ROOT), e.getValue() == null ? List.of() : List.copyOf(e.getValue())));
            this.headers = Map.copyOf(map);
        }
    }

    /**
     * Gets the headers of the response.
     *
     * @return the headers.
     */

            saveError(messages -> messages.addErrorsDocidNotFound(GLOBAL, form.docId));
            return redirect(ErrorAction.class);
        }

        final StreamResponse response =
                asStream(DocumentUtil.getValue(doc, fessConfig.getIndexFieldDocId(), String.class)).contentType("text/html; charset=UTF-8")
                        .data(content.getBytes(Constants.CHARSET_UTF_8));