public T get() {
      // Another variant of Double Checked Locking.
      //
      // We use two volatile reads. We could reduce this to one by
      // putting our fields into a holder class, but (at least on x86)
      // the extra memory consumption and indirection are more
      // expensive than the extra volatile reads.
      long nanos = expirationNanos;
      long now = System.nanoTime();
      if (nanos == 0 || now - nanos >= 0) {

 *   <li>{@link #popularWords()}: Creates a new PopularWordsRequestBuilder for querying popular words.</li>
 *   <li>{@link #refresh()}: Refreshes the suggestion indices.</li>
 *   <li>{@link #shutdown()}: Shuts down the thread pool.</li>
 *   <li>{@link #createIndexIfNothing()}: Creates a new index if no index exists.</li>
 *   <li>{@link #createNextIndex()}: Creates a new index and replaces the current update alias with the new index.</li>

        // Default constructor
    }

    /**
     * Adds an ingester to the factory.
     * The ingester is inserted into the collection and the array is re-sorted by priority.
     * This method is thread-safe.
     *
     * @param ingester the ingester to add
     */
    public synchronized void add(final Ingester ingester) {
        if (logger.isDebugEnabled()) {

                    throwValidationError(messages -> messages.addErrorsCrudCouldNotFindCrudTable(GLOBAL, id), this::asListHtml);
                    return null;
                });
    }

    /**
     * Print a thread dump.
     * @param form The edit form.
     * @return The HTML response.
     */
    @Execute
    @Secured({ ROLE })
    public HtmlResponse threaddump(final EditForm form) {

    public void finalizeReferent() {
      finalizeReferentCalled = true;
    }
  }

  /**
   * Keeps a weak reference to the underlying reference queue. When this reference is cleared, we
   * know that the background thread has stopped and released its strong reference.
   */
  private WeakReference<ReferenceQueue<Object>> queueReference;

  @Test
  public void testThatFinalizerStops() {
    weaklyReferenceQueue();

    public void finalizeReferent() {
      finalizeReferentCalled = true;
    }
  }

  /**
   * Keeps a weak reference to the underlying reference queue. When this reference is cleared, we
   * know that the background thread has stopped and released its strong reference.
   */
  private WeakReference<ReferenceQueue<Object>> queueReference;

  @Test
  public void testThatFinalizerStops() {
    weaklyReferenceQueue();

/**
 * The abstract helper for configuration.
 *
 * This class provides a basic framework for managing configurations that can be reloaded.
 * It includes functionality for updating configurations in a separate thread and controlling the reloading interval.
 */
public abstract class AbstractConfigHelper {

    /**
     * Default constructor.
     */
    public AbstractConfigHelper() {
        // Default constructor
    }

            return null;
        }
    }

    private void loadTestProperties() {
        // Load system.properties from test classpath
        try (InputStream is = Thread.currentThread().getContextClassLoader().getResourceAsStream("system.properties")) {
            if (is != null) {
                Properties props = new Properties();
                props.load(is);

        CountDownLatch latch = new CountDownLatch(2);

        Thread t1 = new Thread(() -> {
            for (int i = 0; i < 100; i++) {
                execJob.jvmOptions("-Xmx" + i + "m");
            }
            latch.countDown();
        });

        Thread t2 = new Thread(() -> {
            for (int i = 0; i < 100; i++) {
                execJob.jvmOptions("-Xms" + i + "m");

            SingletonLaContainerFactory.setExternalContextComponentDefRegister(new GenericExternalContextComponentDefRegister());
            SingletonLaContainerFactory.init();

            final Thread shutdownCallback = new Thread("ShutdownHook") {
                @Override
                public void run() {
                    if (logger.isDebugEnabled()) {
                        logger.debug("Destroying LaContainer..");