// (st_size, as made by say ftruncate(2)), would require a metadata flush.
//
// The aim of fdatasync() is to reduce disk activity for applications that
// do not require all metadata to be synchronized with the disk.
func Fdatasync(f *os.File) error {
	return syscall.Fdatasync(int(f.Fd()))
}

// FadviseDontNeed invalidates page-cache
func FadviseDontNeed(f *os.File) error {

    @Override
    public DefaultSettingsBuildingRequest setSystemProperties(Properties systemProperties) {
        if (systemProperties != null) {
            this.systemProperties = new Properties();
            synchronized (systemProperties) { // avoid concurrent modification if someone else sets/removes an unrelated
                // system property
                this.systemProperties.putAll(systemProperties);
            }

     *
     * @return The compiled Pattern for sensitive key matching
     */
    private static Pattern getSensitivePattern() {
        if (sensitivePattern == null) {
            synchronized (SystemUtil.class) {
                if (sensitivePattern == null) {
                    final String patternStr = System.getProperty(FessConfig.APP_LOG_SENSITIVE_PROPERTY_PATTERN, DEFAULT_SENSITIVE_PATTERN);

    protected CrawlerClientFactory crawlerClientFactory;

    /**
     * List of URLs to be deleted, cached for batch processing.
     * All access is synchronized via indexUpdateCallback lock.
     */
    protected List<String> deleteUrlList = new ArrayList<>();

    /** Maximum size of the delete URL cache before batch deletion is triggered. */

    public void setLabelTypeIds(final String[] labelTypeIds) {
        this.labelTypeIds = labelTypeIds;
    }

    public List<LabelType> getLabelTypeList() {
        if (labelTypeList == null) {
            synchronized (this) {
                if (labelTypeList == null) {
                    final FessConfig fessConfig = ComponentUtil.getFessConfig();

    address: Address,
    call: RealCall,
    routes: List<Route>?,
    requireMultiplexed: Boolean,
  ): RealConnection? {
    for (connection in connections) {
      // In the first synchronized block, acquire the connection if it can satisfy this call.
      val acquired =
        connection.withLock {
          when {
            requireMultiplexed && !connection.isMultiplexed -> {
              false

  static class Key {
    private final int value;
    private WeakReference<String> toString;

    Key(int value) {
      this.value = value;
    }

    @Override
    public synchronized String toString() {
      String s;
      if (toString != null) {
        s = toString.get();
        if (s != null) {
          return s;
        }
      }
      s = Integer.toString(value);

    }
    enumConstantCache.put(enumClass, result);
    return result;
  }

  static <T extends Enum<T>> Map<String, WeakReference<? extends Enum<?>>> getEnumConstants(
      Class<T> enumClass) {
    synchronized (enumConstantCache) {
      Map<String, WeakReference<? extends Enum<?>>> constants = enumConstantCache.get(enumClass);
      if (constants == null) {
        constants = populateCache(enumClass);
      }

     */
    private final int priority;

    /**
     * Parses the phase identifier.
     *
     * @param phase the phase identifier.
     * @return the {@link PhaseId}.
     */
    public static synchronized PhaseId of(String phase) {
        return INSTANCES.computeIfAbsent(phase, PhaseId::new);
    }

    /**
     * Constructor.
     *
     * @param phase the phase identifier string.
     */

    /**
     * Returns a {@link Logger}.
     *
     * @param clazz
     *            Class to be used as the logger category. Must not be {@literal null}.
     * @return {@link Logger}
     */
    public static synchronized Logger getLogger(final Class<?> clazz) {
        assertArgumentNotNull("clazz", clazz);

        if (!initialized) {
            initialize();
        }
        Logger logger = loggers.get(clazz);