* It extends {@link LinkedHashMap} without synchronization. If multiple threads access
 * an instance concurrently, and at least one thread modifies the map structurally,
 * it must be synchronized externally.
 * </p>
 * <p>
 * For thread-safe usage, wrap with {@link java.util.Collections#synchronizedMap(Map)}:
 * </p>
 * <pre>
 * Map&lt;K, V&gt; syncMap = Collections.synchronizedMap(new LruHashMap&lt;&gt;(100));

     *
     * @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);

    }

    /**
     * Plexus: Populates the lifecycle map from the injected list of lifecycle mappings (if not already done).
     */
    private synchronized void initLifecycleMap() {
        if (lifecycleMap == null) {
            lifecycleMap = new HashMap<>();

            if (lifecycles != null) {
                for (Lifecycle lifecycle : lifecycles) {

// (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 {

 * {@link Map} specified in the {@link Table} interface.
 *
 * <p>Note that this implementation is not synchronized. If multiple threads access this table
 * concurrently and one of the threads modifies the table, it must be synchronized externally.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#table">{@code Table}</a>.
 *

    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

    }

    @Test
    public void test_crawlerList_synchronization() {
        // Test that the crawler list is synchronized
        List<org.codelibs.fess.crawler.Crawler> crawlerList = webFsIndexHelper.crawlerList;
        assertTrue(crawlerList.getClass().getName().contains("Synchronized"));
    }

    @Test
    public void test_defaultValues() {

      delegate.clear();
    }

    @Override
    public Collection<V> values() {
      assertTrue(Thread.holdsLock(mutex));
      /* TODO: verify that the Collection is also synchronized? */
      return delegate.values();
    }

    @Override
    public Set<Cell<R, C, V>> cellSet() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.cellSet();
    }

    @Override

    @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);
            }