logger
                .get()
                .log(
                    Level.WARNING,
                    "Error while attempting to shut down the service after failure.",
                    ignored);
          }
          notifyFailed(t);
          // requireNonNull is safe now, just as it was above.
          requireNonNull(runningTask).cancel(false); // prevent future invocations.

  /** Override to call {@code indexOf()} or {@code lastIndexOf()}. */
  protected abstract int find(@Nullable Object o);

  /** Override to return "indexOf" or "lastIndexOf()" for use in failure messages. */
  protected abstract String getMethodName();

  @CollectionSize.Require(absent = ZERO)
  public void testFind_yes() {
    assertEquals(

    delegate.addRelatedGroup(group);
    items.addAll(ImmutableList.copyOf(group));
    return this;
  }

  /** Run tests on equivalence methods, throwing a failure on an invalid test */
  @CanIgnoreReturnValue
  public EquivalenceTester<T> test() {
    for (int run = 0; run < REPETITIONS; run++) {
      testItems();
      delegate.test();
    }
    return this;
  }

    delegate.addRelatedGroup(group);
    items.addAll(ImmutableList.copyOf(group));
    return this;
  }

  /** Run tests on equivalence methods, throwing a failure on an invalid test */
  @CanIgnoreReturnValue
  public EquivalenceTester<T> test() {
    for (int run = 0; run < REPETITIONS; run++) {
      testItems();
      delegate.test();
    }
    return this;
  }

# Application Exception
# ---------------------
# /- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# five framework-embedded messages (don't change key names)
# - - - - - - - - - -/
errors.login.failure = Login failed.
errors.app.illegal.transition = Illegal transition. Please try again.
errors.app.db.already.deleted = It may have been deleted by another process. Please try again.

# Application Exception
# ---------------------
# /- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# five framework-embedded messages (don't change key names)
# - - - - - - - - - -/
errors.login.failure = Login failed.
errors.app.illegal.transition = Illegal transition. Please try again.
errors.app.db.already.deleted = It may have been deleted by another process. Please try again.

            }
        }
        return urlSet;
    }

    /**
     * Processes the response data from a crawled URL, including failure handling.
     * This method extends the base response processing to handle Fess-specific failure
     * URL tracking when certain HTTP status codes are encountered.
     *
     * @param urlQueue the URL queue item that was processed

                    try {
                        keys = new KerberosCredentials().getKeys();
                    } catch (LoginException e) {
                        throw new PACDecodingException("Login failure", e);
                    }
                }

                Map<Integer, KerberosKey> keysByAlgo = new HashMap<>();
                for (KerberosKey key : keys) {

    Validator(GetCheckedTypeValidator validator) {
      this.validator = validator;
    }
  }

  private enum Result {
    SUCCESS(immediateFuture(new Object())),
    FAILURE(immediateFailedFuture(new Exception()));

    final Future<Object> future;

    Result(Future<Object> result) {
      this.future = result;
    }
  }

  private enum ExceptionType {

   *    has since been closed by the server.
   *  * A client timeout (HTTP 408).
   *  * A authorization challenge (HTTP 401 and 407) that is satisfied by the [Authenticator].
   *  * A retryable server failure (HTTP 503 with a `Retry-After: 0` response header).
   *  * A misdirected request (HTTP 421) on a coalesced connection.
   */
  open fun isOneShot(): Boolean = false

  /**