extends ForwardingMap<K, V> implements BiMap<K, V>, Serializable {

  private transient Map<K, V> delegate;

  @RetainedWith private transient AbstractBiMap<V, K> inverse;

  /** Package-private constructor for creating a map-backed bimap. */
  AbstractBiMap(Map<K, V> forward, Map<V, K> backward) {
    inverse = checkMapsAndMakeInverse(forward, backward);
    delegate = forward;
  }

     * Merges response data from the crawler into the original data map.
     * Handles special ".overwrite" suffix fields by removing the suffix and overwriting the base field.
     *
     * @param dataMap the original data map to merge into
     * @param responseDataMap the response data map from the crawler
     */
    protected void mergeResponseData(final Map<String, Object> dataMap, final Map<String, Object> responseDataMap) {

      ImmutableMap<K, V> map = super.buildOrThrow();
      if (map.isEmpty()) {
        return of();
      }
      return new RegularImmutableBiMap<K, V>(super.buildOrThrow());
    }

    @Override
    ImmutableBiMap<K, V> buildJdkBacked() {
      return build();
    }
  }

  public static <K, V> ImmutableBiMap<K, V> copyOf(Map<? extends K, ? extends V> map) {
    if (map instanceof ImmutableBiMap) {

        final Map<String, String> paramEnvMap = systemHelper.getFilteredEnvMap(fessConfig.getCrawlerDataEnvParamKeyPattern());
        final Map<String, String> configParamMap = config.getHandlerParameterMap().entrySet().stream().map(e -> {
            final String key = e.getKey();
            String value = e.getValue();
            for (final Map.Entry<String, String> entry : paramEnvMap.entrySet()) {

    public CaseInsensitiveSet(final int initialCapacity) {
        map = new CaseInsensitiveMap<>(initialCapacity);
    }

    @Override
    public Iterator<String> iterator() {
        return map.keySet().iterator();
    }

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

    @Override
    public boolean isEmpty() {
        return map.isEmpty();
    }

    @Override

     */
    @Nonnull
    List<String> getInactiveProfileIds();

    /**
     * Provides a map of system properties.
     */
    @Nonnull
    Map<String, String> getSystemProperties();

    /**
     * Provides a map of user properties.
     * User properties
     */
    @Nonnull
    Map<String, String> getUserProperties();

    @Nonnull
    RepositoryMerging getRepositoryMerging();

     */
    @Override
    public void setCacheMap(final Map<String, DfsReferralDataInternal> map) {
        this.map = map;
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.internal.dfs.DfsReferralDataInternal#replaceCache()
     */
    @Override
    public void replaceCache() {
        if (this.map != null && this.key != null) {

  /**
   * Returns an unmodifiable map containing the entries from the left map whose keys are not present
   * in the right map.
   */
  Map<K, V> entriesOnlyOnLeft();

  /**
   * Returns an unmodifiable map containing the entries from the right map whose keys are not
   * present in the left map.
   */
  Map<K, V> entriesOnlyOnRight();

  /**

                PluginContainer target, PluginContainer source, boolean sourceDominant, Map<Object, Object> context) {
            List<Plugin> src = source.getPlugins();
            if (!src.isEmpty()) {
                List<Plugin> tgt = target.getPlugins();

                Map<Object, Plugin> merged = new LinkedHashMap<>((src.size() + tgt.size()) * 2);

                for (Plugin element : tgt) {

   */

  private transient Map<K, Collection<V>> map;
  private transient int totalSize;

  /**
   * Creates a new multimap that uses the provided map.
   *
   * @param map place to store the mapping from each key to its corresponding values
   * @throws IllegalArgumentException if {@code map} is not empty
   */
  protected AbstractMapBasedMultimap(Map<K, Collection<V>> map) {
    checkArgument(map.isEmpty());