thread.start();
        thread.join();

        assertNull(exceptionHolder[0]);
        assertNotNull(clientHolder[0]);
    }

    // Test repeated instantiation
    @Test
    public void test_repeatedInstantiation() {
        // Test that repeated instantiation works correctly
        for (int i = 0; i < 10; i++) {
            CrawlerEngineClient client = new CrawlerEngineClient();
            assertNotNull(client);
        }

   * use the {@code ArrayList} {@linkplain ArrayList#ArrayList() constructor} directly, taking
   * advantage of <a
   * href="https://docs.oracle.com/javase/tutorial/java/generics/genTypeInference.html#type-inference-instantiation">"diamond"
   * syntax</a>.
   */
  @SuppressWarnings("NonApiType") // acts as a direct substitute for a constructor call
  public static <E extends @Nullable Object> ArrayList<E> newArrayList() {

   * use the {@code ArrayList} {@linkplain ArrayList#ArrayList() constructor} directly, taking
   * advantage of <a
   * href="https://docs.oracle.com/javase/tutorial/java/generics/genTypeInference.html#type-inference-instantiation">"diamond"
   * syntax</a>.
   */
  @SuppressWarnings("NonApiType") // acts as a direct substitute for a constructor call
  public static <E extends @Nullable Object> ArrayList<E> newArrayList() {

   * use the {@code HashSet} constructor directly, taking advantage of <a
   * href="https://docs.oracle.com/javase/tutorial/java/generics/genTypeInference.html#type-inference-instantiation">"diamond"
   * syntax</a>.
   */
  @SuppressWarnings("NonApiType") // acts as a direct substitute for a constructor call
  public static <E extends @Nullable Object> HashSet<E> newHashSet() {

   * use the {@code HashSet} constructor directly, taking advantage of <a
   * href="https://docs.oracle.com/javase/tutorial/java/generics/genTypeInference.html#type-inference-instantiation">"diamond"
   * syntax</a>.
   */
  @SuppressWarnings("NonApiType") // acts as a direct substitute for a constructor call
  public static <E extends @Nullable Object> HashSet<E> newHashSet() {

            : UnsafeByteArray.UNSAFE_BIG_ENDIAN;
      }
    } catch (Throwable t) {
      // ensure we really catch *everything*
    }

    return JavaLittleEndianBytes.INSTANCE;
  }

  /** Deter instantiation of this class. */
  private LittleEndianByteArray() {}

   * use the {@code HashMap} constructor directly, taking advantage of <a
   * href="https://docs.oracle.com/javase/tutorial/java/generics/genTypeInference.html#type-inference-instantiation">"diamond"
   * syntax</a>.
   *
   * @return a new, empty {@code HashMap}
   */
  @SuppressWarnings("NonApiType") // acts as a direct substitute for a constructor call

   * use the {@code HashMap} constructor directly, taking advantage of <a
   * href="https://docs.oracle.com/javase/tutorial/java/generics/genTypeInference.html#type-inference-instantiation">"diamond"
   * syntax</a>.
   *
   * @return a new, empty {@code HashMap}
   */
  @SuppressWarnings("NonApiType") // acts as a direct substitute for a constructor call

 * </ul>
 */
public class Constants extends CoreLibConstants {

    /**
     * Private constructor to prevent instantiation of this utility class.
     * This class contains only static constants and should not be instantiated.
     */
    private Constants() {
        // Utility class - no instantiation
    }

    // ============================================================
    // System and UI Constants

        public Integer hotThread;

        /**
         * Default constructor for Options.
         * Protected to allow subclassing while preventing direct instantiation.
         */
        protected Options() {
            // nothing
        }

        /**
         * Parses the web configuration IDs string into a list.
         *