* @return The created OpenSearch client.
     */
    protected Client createClient() {
        final String[] hosts =
                split(address, ",").get(stream -> stream.map(String::trim).filter(StringUtil::isNotEmpty).toArray(n -> new String[n]));
        final Settings settings = Settings.builder().putList("http.hosts", hosts).build();
        return new HttpClient(settings, null);
    }

    /**

        }
        try {
          waitForIo()
        } finally {
          if (doReadTimeout) {
            readTimeout.exitAndThrowIfTimedOut()
          }
        }
      }
      if (headersQueue.isNotEmpty()) {
        return headersQueue.removeFirst()
      }
      throw errorException ?: StreamResetException(errorCode!!)
    }
  }

  /**
   * Returns the trailers if they're immediately available.

     *
     * @param collection the collection
     * @return {@literal true} if the collection is not {@literal null} and not empty
     */
    public static boolean isNotEmpty(final Collection<?> collection) {
        return !isEmpty(collection);
    }

    /**
     * Returns {@literal true} if the given {@link Map} is {@literal null} or empty.
     *

      if (MAGIC != magic ||
        VERSION_1 != version ||
        appVersion.toString() != appVersionString ||
        valueCount.toString() != valueCountString ||
        blank.isNotEmpty()
      ) {
        throw IOException(
          "unexpected journal header: [$magic, $version, $valueCountString, $blank]",
        )
      }

      var lineCount = 0
      while (true) {

            if (StringUtil.isNotBlank(requiredKeysStr) && StreamUtil.split(requiredKeysStr, ",")
                    .get(stream -> stream.map(String::trim).filter(StringUtil::isNotEmpty).anyMatch(name -> {
                        final String[] values = req.getParameterValues(name);
                        if (values == null || values.length == 0 || StringUtil.isEmpty(values[0])) {

  ) {
    assertLockNotHeld()

    ignoreIoExceptions {
      shutdown(connectionCode)
    }

    var streamsToClose: Array<Http2Stream>? = null
    withLock {
      if (streams.isNotEmpty()) {
        streamsToClose = streams.values.toTypedArray()
        streams.clear()
      }
    }

    streamsToClose?.forEach { stream ->
      ignoreIoExceptions {

        System.setProperty(Constants.FESS_LOG_LEVEL, logLevel.toString());
        split(ComponentUtil.getFessConfig().getLoggingAppPackages(), ",")
                .of(stream -> stream.map(String::trim).filter(StringUtil::isNotEmpty).forEach(s -> Configurator.setLevel(s, logLevel)));
    }

    /**
     * Gets the current log level.
     *
     * @return The current log level.
     */
    public String getLogLevel() {

     */
    protected static String constructRedirectLocation(final String url, final String location) {
        try {
            URI uri = new URI(url);
            if (StringUtil.isNotEmpty(location)) {
                uri = uri.resolve(location.replace(" ", "%20"));
            }
            return uri.normalize().toASCIIString();
        } catch (URISyntaxException e) {

     * @param state The state parameter to validate.
     * @return The validated state data.
     */
    protected StateData validateState(final HttpSession session, final String state) {
        if (StringUtils.isNotEmpty(state)) {
            final StateData stateDataInSession = removeStateFromSession(session, state);
            if (stateDataInSession != null) {
                return stateDataInSession;
            }
        }

import assertk.assertions.isFalse
import assertk.assertions.isGreaterThanOrEqualTo
import assertk.assertions.isIn
import assertk.assertions.isInstanceOf
import assertk.assertions.isLessThan
import assertk.assertions.isNotEmpty
import assertk.assertions.isNull
import assertk.assertions.isTrue
import assertk.fail
import java.io.File
import java.io.IOException
import java.io.InputStream
import java.net.ConnectException