*     source-compatible</a> since 4.0)
 */
@GwtCompatible
/*
 * The type parameter is <T> rather than <T extends @Nullable> so that we can use T in the
 * doEquivalent and doHash methods to indicate that the parameter cannot be null.
 */
@SuppressWarnings("UngroupedOverloads")
public abstract class Equivalence<T> implements BiPredicate<@Nullable T, @Nullable T> {
  /** Constructor for use by subclasses. */
  protected Equivalence() {}

            final String url = responseData != null ? responseData.getUrl() : "unknown";
            throw new CrawlingAccessException("No response body for URL: " + url + ". Cannot transform empty response.");
        }

        final ResultData resultData = new ResultData();
        resultData.setTransformerName(getName());
        try {

     *
     * @param queryContext the query context containing the query string
     * @param context a consumer for additional query context customization
     * @throws InvalidQueryException if the query string cannot be parsed
     */
    public void buildBaseQuery(final QueryContext queryContext, final Consumer<QueryContext> context) {
        try {
            final Query query = getQueryParser().parse(queryContext.getQueryString());

 * object.
 *
 * <p><b>Comparison to {@code java.util.Optional} (JDK 8 and higher):</b> A new {@code Optional}
 * class was added for Java 8. The two classes are extremely similar, but incompatible (they cannot
 * share a common supertype). <i>All</i> known differences are listed either here or with the
 * relevant methods below.
 *
 * <ul>
 *   <li>This class is serializable; {@code java.util.Optional} is not.

func preSignV4(req *http.Request, accessKeyID, secretAccessKey string, expires int64) error {
	// Presign is not needed for anonymous credentials.
	if accessKeyID == "" || secretAccessKey == "" {
		return errors.New("Presign cannot be generated without access and secret keys")
	}

	region := globalSite.Region()
	date := UTCNow()
	scope := getScope(date, region)
	credential := fmt.Sprintf("%s/%s", accessKeyID, scope)

 * object.
 *
 * <p><b>Comparison to {@code java.util.Optional} (JDK 8 and higher):</b> A new {@code Optional}
 * class was added for Java 8. The two classes are extremely similar, but incompatible (they cannot
 * share a common supertype). <i>All</i> known differences are listed either here or with the
 * relevant methods below.
 *
 * <ul>
 *   <li>This class is serializable; {@code java.util.Optional} is not.

          notices within Derivative Works that You distribute, alongside
          or as an addendum to the NOTICE text from the Work, provided
          that such additional attribution notices cannot be construed
          as modifying the License.

      You may add Your own copyright statement to Your modifications and
      may provide additional or different license terms and conditions

	resource := args.Resources[0]
	if lri, reply = l.lockMap[resource]; !reply {
		// No lock is held on the given name
		return true, nil
	}
	if isWriteLock(lri) {
		// A write-lock is held, cannot release a read lock
		return false, fmt.Errorf("RUnlock attempted on a write locked entity: %s", resource)
	}
	l.removeEntry(resource, args, &lri)
	return reply, nil
}

type lockStats struct {

    request: Request,
    newRoutePlanner: Boolean,
    chain: RealInterceptorChain,
  ) {
    check(interceptorScopedExchange == null)

    withLock {
      check(!responseBodyOpen) {
        "cannot make a new request because the previous response is still open: " +
          "please call response.close()"
      }
      check(!requestBodyOpen && !socketSourceOpen && !socketSinkOpen)
    }

        if (StringUtil.isBlank(crawlingInfoId)) {
            throw new CrawlingAccessException("sessionId is null. Cannot access document without a valid session ID.");
        }

        final CrawlerClientFactory crawlerClientFactory = crawlingConfig.initializeClientFactory(ComponentUtil::getCrawlerClientFactory);