interface DocumentCheck : InterpretationStepFeatureHandler<InterpretationStepFeature.DocumentChecks> {
    val checkKey: String

    override fun shouldHandleFeature(feature: InterpretationStepFeature.DocumentChecks): Boolean =
        checkKey in feature.checkKeys

    fun detectFailures(document: DeclarativeDocument, resolutionContainer: DocumentResolutionContainer): List<DocumentCheckFailure>
}

    val feature = SettingsBlockCheckFeature()

    class SettingsBlockCheckFeature() : InterpretationStepFeature.DocumentChecks, Serializable {
        override val checkKeys: Iterable<String> = listOf(checkKey)
    }

    override val checkKey: String
        get() = SettingsBlocksCheck::class.java.name

    enum class SpecialOrderBlock {
        PLUGIN_MANAGEMENT, PLUGINS
    }

     */

    @Override
    @ParametricNullness
    K checkKey(@ParametricNullness K key) {
      return inverse.checkValue(key);
    }

    @Override
    @ParametricNullness
    V checkValue(@ParametricNullness V value) {
      return inverse.checkKey(value);
    }

    /**
     * @serialData the forward bimap
     */

     */

    @Override
    @ParametricNullness
    K checkKey(@ParametricNullness K key) {
      return inverse.checkValue(key);
    }

    @Override
    @ParametricNullness
    V checkValue(@ParametricNullness V value) {
      return inverse.checkKey(value);
    }

    /**
     * @serialData the forward bimap
     */

    this.keyTypeOrObjectUnderJ2cl = keyType;
  }

  // Overriding these 3 methods to show that values may be null (but not keys)

  @Override
  K checkKey(K key) {
    return checkNotNull(key);
  }

  @CanIgnoreReturnValue
  @Override
  @SuppressWarnings("RedundantOverride") // b/192446478: RedundantOverride ignores some annotations.

    this.keyTypeOrObjectUnderJ2cl = keyType;
  }

  // Overriding these 3 methods to show that values may be null (but not keys)

  @Override
  K checkKey(K key) {
    return checkNotNull(key);
  }

  @CanIgnoreReturnValue
  @Override
  @SuppressWarnings("RedundantOverride") // b/192446478: RedundantOverride ignores some annotations.

  }

  /** Returns the associated value type. */
  @GwtIncompatible
  public Class<V> valueType() {
    return valueTypeOrObjectUnderJ2cl;
  }

  @Override
  K checkKey(K key) {
    return checkNotNull(key);
  }

  @Override
  V checkValue(V value) {
    return checkNotNull(value);
  }

  /**

  }

  /** Returns the associated value type. */
  @GwtIncompatible
  public Class<V> valueType() {
    return valueTypeOrObjectUnderJ2cl;
  }

  @Override
  K checkKey(K key) {
    return checkNotNull(key);
  }

  @Override
  V checkValue(V value) {
    return checkNotNull(value);
  }

  /**

			// to retry with 503 errors when server is coming up.
			return auth.Credentials{}, false, ErrIAMNotInitialized
		}

		// Check if the access key is part of users credentials.
		u, ok, err := globalIAMSys.CheckKey(r.Context(), accessKey)
		if err != nil {
			return auth.Credentials{}, false, ErrIAMNotInitialized
		}
		if !ok {
			// Credentials could be valid but disabled - return a different
			// error in such a scenario.

				logErr := fmt.Errorf("failed to delete extraneous LDAP DN mapping for `%s`: %w", origKeys[0], delErr)
				iamLogIf(ctx, logErr)
			}
		}
	}
	return nil
}

// CheckKey validates the incoming accessKey
func (sys *IAMSys) CheckKey(ctx context.Context, accessKey string) (u UserIdentity, ok bool, err error) {
	if !sys.Initialized() {
		return u, false, nil
	}

	if accessKey == globalActiveCred.AccessKey {