}
            return new SpnegoCredential(username[0]);
        }).orElseGet(() -> null);

    }

    /**
     * SPNEGO filter configuration implementation.
     *
     * This inner class provides configuration parameters for the SPNEGO filter,
     * mapping system properties to SPNEGO configuration values. It handles
     * various authentication settings including Kerberos configuration,

				// concurrently, check for it before we
				// write the filler byte.
				select {
				case err := <-doneCh:
					if err != nil {
						write([]byte{1})
						write([]byte(err.Error()))
					} else {
						write([]byte{0})
					}
					return
				default:
				}

				// Response not ready, write a filler byte.
				write([]byte{32})
				if canWrite {
					xhttp.Flush(w)
				}

   * <p><b>{@code Stream} equivalent:</b> {@link Stream#filter}.
   */
  public static <T extends @Nullable Object> Iterable<T> filter(
      Iterable<T> unfiltered, Predicate<? super T> retainIfTrue) {
    checkNotNull(unfiltered);
    checkNotNull(retainIfTrue);
    return new FluentIterable<T>() {
      @Override
      public Iterator<T> iterator() {
        return Iterators.filter(unfiltered.iterator(), retainIfTrue);
      }

   * it does.
   *
   * <p>The caller is responsible for ensuring that the returned stream is closed. For example:
   *
   * {@snippet :
   * try (Stream<String> lines = source.lines()) {
   *   lines.map(...)
   *      .filter(...)
   *      .forEach(...);
   * }
   * }
   *

   * it does.
   *
   * <p>The caller is responsible for ensuring that the returned stream is closed. For example:
   *
   * {@snippet :
   * try (Stream<String> lines = source.lines()) {
   *   lines.map(...)
   *      .filter(...)
   *      .forEach(...);
   * }
   * }
   *

   * <p><b>{@code Stream} equivalent:</b> {@link Stream#filter}.
   */
  public static <T extends @Nullable Object> Iterable<T> filter(
      Iterable<T> unfiltered, Predicate<? super T> retainIfTrue) {
    checkNotNull(unfiltered);
    checkNotNull(retainIfTrue);
    return new FluentIterable<T>() {
      @Override
      public Iterator<T> iterator() {
        return Iterators.filter(unfiltered.iterator(), retainIfTrue);
      }

    }

    /**
     * Adds a filter to the query processing chain.
     * The filter chain is recreated after adding the filter.
     *
     * @param filter the filter to add
     */
    public void addFilter(final Filter filter) {
        filterList.add(filter);
        createFilterChain();
    }

    /**
     * Creates the filter chain by combining all registered filters.

        // Verify iteration
        assertTrue(iterator.hasNext());
        assertSame(resource, iterator.next());
        assertFalse(iterator.hasNext());

        // With filter, resource should be closed due to try-with-resources
        verify(filter).accept(resource);
        verify(resource).close();
    }

    @Test
    @DisplayName("Iterator with rejecting filter - finds next acceptable")

        assertFalse(filter(createUnfiltered(contents), EVEN).contains(new Object()));
      }
    }

    public void testAddAllFailsAtomically() {
      ImmutableList<Integer> toAdd = ImmutableList.of(2, 4, 3);
      for (List<Integer> contents : SAMPLE_INPUTS) {
        C filtered = filter(createUnfiltered(contents), EVEN);
        C filteredToModify = filter(createUnfiltered(contents), EVEN);

          "tokenizer": "standard",
          "filter": [
            "truncate20_filter",
            "lowercase",
            "arabic_stop",
            "arabic_normalization",
            "arabic_keywords",
            "arabic_override",
            "arabic_stemmer"
          ]
        },
        "armenian_analyzer": {
          "tokenizer":  "standard",
          "filter": [
            "truncate20_filter",