// ErrRegistered registered
	ErrRegistered = errors.New("registered")
	// ErrInvalidField invalid field
	ErrInvalidField = errors.New("invalid field")
	// ErrEmptySlice empty slice found
	ErrEmptySlice = errors.New("empty slice found")
	// ErrDryRunModeUnsupported dry run mode unsupported
	ErrDryRunModeUnsupported = errors.New("dry run mode unsupported")
	// ErrInvalidDB invalid db
	ErrInvalidDB = errors.New("invalid db")

   * exists. The resulting range may be empty if the two ranges are adjacent but non-overlapping.
   *
   * <p>For example, the gap of {@code [1..5]} and {@code (7..10)} is {@code (5..7]}. The resulting
   * range may be empty; for example, the gap between {@code [1..5)} {@code [5..7)} yields the empty
   * range {@code [5..5)}.
   *

  /**
   * Returns the minimal range {@linkplain Range#encloses(Range) enclosing} the ranges in this
   * {@code RangeMap}.
   *
   * @throws NoSuchElementException if this range map is empty
   */
  Range<K> span();

  /**
   * Maps a range to a specified value (optional operation).
   *
   * <p>Specifically, after a call to {@code put(range, value)}, if {@link

  // `nil` specifies that the distinguisher is disabled and thus will always be the empty string.
  // +optional
  optional FlowDistinguisherMethod distinguisherMethod = 3;

  // `rules` describes which requests will match this flow schema. This FlowSchema matches a request if and only if
  // at least one member of rules matches the request.
  // if it is an empty slice, there will be no requests matching the FlowSchema.
  // +listType=atomic

  // `nil` specifies that the distinguisher is disabled and thus will always be the empty string.
  // +optional
  optional FlowDistinguisherMethod distinguisherMethod = 3;

  // `rules` describes which requests will match this flow schema. This FlowSchema matches a request if and only if
  // at least one member of rules matches the request.
  // if it is an empty slice, there will be no requests matching the FlowSchema.
  // +listType=atomic

          .put(Locale.class, Locale.US)
          .put(Optional.class, Optional.empty())
          .put(OptionalInt.class, OptionalInt.empty())
          .put(OptionalLong.class, OptionalLong.empty())
          .put(OptionalDouble.class, OptionalDouble.empty())
          .put(UUID.class, UUID.randomUUID())
          // common.base
          .put(CharMatcher.class, CharMatcher.none())

            return name;
        }
    }

    protected String getHostOnFile(final String url) {
        if (StringUtil.isBlank(url)) {
            return StringUtil.EMPTY; // empty
        }

        if (url.startsWith("file:////")) {
            final String value = decodeUrlAsName(url.substring(9), true);
            final int pos = value.indexOf('/');
            if (pos > 0) {

                logger.debug("Failed to parse a value of {}.", name, e);
            }
        }
        return OptionalObject.empty();
    }

    @Override
    public OptionalThing<Locale> getRequestedLocale(final RequestManager requestManager) {
        return OptionalObject.empty(); // means browser default
    }

    // ===================================================================================

  // Label query over pods whose evictions are managed by the disruption
  // budget.
  // A null selector selects no pods.
  // An empty selector ({}) also selects no pods, which differs from standard behavior of selecting all pods.
  // In policy/v1, an empty selector will select all pods in the namespace.
  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.LabelSelector selector = 2;

                return false;
            }

            @Override
            public String getHttpProxyHost() {
                return StringUtil.EMPTY;
            }

            @Override
            public String getHttpProxyPort() {
                return StringUtil.EMPTY;
            }
        };
        ComponentUtil.setFessConfig(fessConfig);
        SystemHelper systemHelper = new SystemHelper() {
            @Override