* actions taken by the java garbage collection system:
 *
 * <ul>
 *   <li>invoking the {@code finalize} methods of unreachable objects
 *   <li>clearing weak references to unreachable referents
 *   <li>enqueuing weak references to unreachable referents in their reference queue
 * </ul>
 *
 * <p>This class uses (possibly repeated) invocations of {@link java.lang.System#gc()} to cause

   *
   * @return true if the caller should continue to clean up references from the queue, false if the
   *     associated FinalizableReferenceQueue is no longer referenced.
   */
  private boolean finalizeReference(Reference<?> reference, Method finalizeReferentMethod) {
    /*
     * This is for the benefit of phantom references. Weak and soft references will have already
     * been cleared by this point.
     */

 * actions taken by the java garbage collection system:
 *
 * <ul>
 *   <li>invoking the {@code finalize} methods of unreachable objects
 *   <li>clearing weak references to unreachable referents
 *   <li>enqueuing weak references to unreachable referents in their reference queue
 * </ul>
 *
 * <p>This class uses (possibly repeated) invocations of {@link java.lang.System#gc()} to cause

   *
   * @return true if the caller should continue to clean up references from the queue, false if the
   *     associated FinalizableReferenceQueue is no longer referenced.
   */
  private boolean finalizeReference(Reference<?> reference, Method finalizeReferentMethod) {
    /*
     * This is for the benefit of phantom references. Weak and soft references will have already
     * been cleared by this point.
     */

            return 0;
          }
        };

    assertEquals(0, (int) iter.next());

    assertThrows(UnsupportedOperationException.class, iter::remove);
  }


  @GwtIncompatible // weak references
  @J2ktIncompatible
  public void testFreesNextReference() {
    Iterator<Object> itr =
        new AbstractIterator<Object>() {
          @Override
          public Object computeNext() {

 *       public void finalizeReferent() {
 *         references.remove(this):
 *         if (!serverSocket.isClosed()) {
 *           ...log a message about how nobody called close()...
 *           try {
 *             serverSocket.close();
 *           } catch (IOException e) {
 *             ...
 *           }
 *         }
 *       }
 *     };
 *     references.add(reference);
 *     return myServer;
 *   }
 *

    assertThrows(NoSuchElementException.class, iter::next);
    assertThrows(NoSuchElementException.class, iter::peek);
  }


  @J2ktIncompatible // weak references, details of GC
  @GwtIncompatible // weak references
  public void testFreesNextReference() {
    Iterator<Object> itr =
        new AbstractIterator<Object>() {
          @Override
          public Object computeNext() {

    assertThrows(NoSuchElementException.class, iter::next);
    assertThrows(NoSuchElementException.class, iter::peek);
  }


  @J2ktIncompatible // weak references, details of GC
  @GwtIncompatible // weak references
  public void testFreesNextReference() {
    Iterator<Object> itr =
        new AbstractIterator<Object>() {
          @Override
          public Object computeNext() {

 *       public void finalizeReferent() {
 *         references.remove(this):
 *         if (!serverSocket.isClosed()) {
 *           ...log a message about how nobody called close()...
 *           try {
 *             serverSocket.close();
 *           } catch (IOException e) {
 *             ...
 *           }
 *         }
 *       }
 *     };
 *     references.add(reference);
 *     return myServer;
 *   }
 *

    assertThat(sepStopwatchA.get()).isNotNull();
    // Clear all references to the Stopwatch and wait for it to be gc'd.
    sepStopwatchA.set(null);
    GcFinalization.awaitClear(sepStopwatchRef.get());
    // Return a weak reference to the parallel ClassLoader. This is the reference that should
    // eventually become clear if there are no other references to the ClassLoader.
    return new WeakReference<ClassLoader>(sepLoader);
  }