public boolean containsKey(@Nullable Object key) {
    if (unfiltered.containsKey(key)) {
      @SuppressWarnings("unchecked") // k is equal to a K, if not one itself
      K k = (K) key;
      return keyPredicate.apply(k);
    }
    return false;
  }

  @Override
  public Collection<V> removeAll(@Nullable Object key) {
    return containsKey(key) ? unfiltered.removeAll(key) : unmodifiableEmptyCollection();
  }

    Function<String, String> internerFunction =
        Interners.asFunction(Interners.<String>newStrongInterner());

    assertThat(internerFunction.apply(canonical)).isSameInstanceAs(canonical);
    assertThat(internerFunction.apply(not)).isSameInstanceAs(canonical);
  }

  public void testNullPointerExceptions() {
    new NullPointerTester().testAllPublicStaticMethods(Interners.class);
  }

    Function<String, String> internerFunction =
        Interners.asFunction(Interners.<String>newStrongInterner());

    assertThat(internerFunction.apply(canonical)).isSameInstanceAs(canonical);
    assertThat(internerFunction.apply(not)).isSameInstanceAs(canonical);
  }

  public void testNullPointerExceptions() {
    new NullPointerTester().testAllPublicStaticMethods(Interners.class);
  }

    ListenableFuture<? extends V> doFallback(
        AsyncFunction<? super X, ? extends V> fallback, X cause) throws Exception {
      ListenableFuture<? extends V> output = fallback.apply(cause);
      checkNotNull(
          output,
          "AsyncFunction.apply returned null instead of a Future. "
              + "Did you mean to return immediateFuture(null)? %s",
          fallback);
      return output;
    }

    @Override

            String name = (String) e.nextElement();
            String value = props.getProperty(name);
            if (value == null) {
                value = callback.apply(name);
            }
            if (name.startsWith(OVERRIDE_PREFIX)) {
                String overrideName = name.substring(OVERRIDE_PREFIX.length());

             */
            Plugin plugin = Plugin.newBuilder()
                    .groupId(interpolator.apply(extension.getGroupId()))
                    .artifactId(interpolator.apply(extension.getArtifactId()))
                    .version(interpolator.apply(extension.getVersion()))
                    .build();

            DependencyResult result = pluginDependenciesResolver.resolveCoreExtension(

                v = cb.apply(s.substring(prefix.length()));
            }
            return v;
        };
    }

    @SafeVarargs
    @Nonnull
    public static UnaryOperator<String> or(UnaryOperator<String>... callbacks) {
        return s -> {
            for (UnaryOperator<String> cb : callbacks) {
                String r = cb.apply(s);
                if (r != null) {

     * Extracts text content from a single node using XPath expression.
     *
     * @param document the parsed HTML document
     * @param xpath the XPath expression to evaluate
     * @param pruneFunc the function to apply for node pruning
     * @return the extracted text content
     */
    protected String getSingleNodeValue(final Document document, final String xpath, final UnaryOperator<Node> pruneFunc) {
        StringBuilder buf = null;

     */
    protected Function<Map<String, Object>, Long> requestHandler = params -> {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final String[] ids = idFinder.apply(params);
        if (ids.length == 0) {
            return 0L;
        }
        final SearchEngineClient client = ComponentUtil.getSearchEngineClient();
        if (bulkRequestBuilder == null) {

	o.FilterPrefix = strings.Trim(o.FilterPrefix, slashSeparator)

	if strings.Contains(o.FilterPrefix, slashSeparator) {
		// Sanity check, should not happen.
		o.FilterPrefix = ""
	}
}

// filter will apply the options and return the number of objects requested by the limit.
// Will return io.EOF if there are no more entries with the same filter.
// The last entry can be used as a marker to resume the listing.