return;
    }
    fail("Should have caught jdk6 bug in target iterator");
  }

  private static final int STEPS = 3;

  static class TesterThatCountsCalls extends IteratorTester<Integer> {
    TesterThatCountsCalls() {
      super(STEPS, MODIFIABLE, newArrayList(1), IteratorTester.KnownOrder.KNOWN_ORDER);
    }

    int numCallsToNewTargetIterator;
    int numCallsToVerify;

        ArrayReference<? extends L> arrayRef = (ArrayReference<? extends L>) ref;
        // Try to clear out the array slot, n.b. if we fail that is fine, in either case the
        // arrayRef will be out of the array after this step.
        locks.compareAndSet(arrayRef.index, arrayRef, null);
      }
    }

    @Override
    public int size() {
      return size;
    }