// cleared.
  @J2ktIncompatible
  private WeakReference<?> doTestClassUnloading() throws Exception {
    URLClassLoader shadowLoader = new URLClassLoader(getClassPathUrls(), null);
    @SuppressWarnings("unchecked")
    Class<TestEnum> shadowTestEnum =
        (Class<TestEnum>) Class.forName(TestEnum.class.getName(), false, shadowLoader);

  }

  private WeakReference<ClassLoader> useFrqInSeparateLoader() throws Exception {
    ClassLoader myLoader = getClass().getClassLoader();
    URLClassLoader sepLoader = new URLClassLoader(getClassPathUrls(), myLoader.getParent());
    // sepLoader is the loader that we will use to load the parallel FinalizableReferenceQueue (FRQ)
    // and friends, and that we will eventually expect to see garbage-collected. The assumption

        error.initCause(e);
        throw error;
      }
    }
    return urls.build().toArray(new URL[0]);
  }

  /** Returns the URLs in the class path. */
  static URL[] getClassPathUrls() {
    return ClassPathUtil.class.getClassLoader() instanceof URLClassLoader
        ? ((URLClassLoader) ClassPathUtil.class.getClassLoader()).getURLs()
        : parseJavaClassPath();
  }

        error.initCause(e);
        throw error;
      }
    }
    return urls.build().toArray(new URL[0]);
  }

  /** Returns the URLs in the class path. */
  static URL[] getClassPathUrls() {
    return ClassPathUtil.class.getClassLoader() instanceof URLClassLoader
        ? ((URLClassLoader) ClassPathUtil.class.getClassLoader()).getURLs()
        : parseJavaClassPath();
  }

  // cleared.
  @J2ktIncompatible
  private WeakReference<?> doTestClassUnloading() throws Exception {
    URLClassLoader shadowLoader = new URLClassLoader(getClassPathUrls(), null);
    @SuppressWarnings("unchecked")
    Class<TestEnum> shadowTestEnum =
        (Class<TestEnum>) Class.forName(TestEnum.class.getName(), false, shadowLoader);

  }

  private WeakReference<ClassLoader> useFrqInSeparateLoader() throws Exception {
    ClassLoader myLoader = getClass().getClassLoader();
    URLClassLoader sepLoader = new URLClassLoader(getClassPathUrls(), myLoader.getParent());
    // sepLoader is the loader that we will use to load the parallel FinalizableReferenceQueue (FRQ)
    // and friends, and that we will eventually expect to see garbage-collected. The assumption

    System.setProperty("guava.concurrent.generate_cancellation_cause", "true");
    String concurrentPackage = SettableFuture.class.getPackage().getName();
    classReloader =
        new URLClassLoader(ClassPathUtil.getClassPathUrls()) {
          @GuardedBy("loadedClasses")
          final Map<String, Class<?>> loadedClasses = new HashMap<>();

          @Override
          public Class<?> loadClass(String name) throws ClassNotFoundException {

    System.setProperty("guava.concurrent.generate_cancellation_cause", "true");
    String concurrentPackage = SettableFuture.class.getPackage().getName();
    classReloader =
        new URLClassLoader(ClassPathUtil.getClassPathUrls()) {
          @GuardedBy("loadedClasses")
          final Map<String, Class<?>> loadedClasses = new HashMap<>();

          @Override
          public Class<?> loadClass(String name) throws ClassNotFoundException {

    // we delegate to the current classloader so both loaders agree on classes like TestCase
    return new URLClassLoader(ClassPathUtil.getClassPathUrls(), classLoader) {
      @Override
      public Class<?> loadClass(String name) throws ClassNotFoundException {
        if (blocklist.contains(name)) {

    ClassLoader classLoader = AbstractFutureFallbackAtomicHelperTest.class.getClassLoader();
    // we delegate to the current classloader so both loaders agree on classes like TestCase
    return new URLClassLoader(ClassPathUtil.getClassPathUrls(), classLoader) {
      @Override
      public Class<?> loadClass(String name) throws ClassNotFoundException {
        if (disallowedClassNames.contains(name)) {