assertEquals(0, aa.length());
    assertThrows(IndexOutOfBoundsException.class, () -> aa.get(0));
  }

  /** constructor with length zero has size 0 and contains no elements */
  public void testConstructorZeroLength() {
    AtomicDoubleArray aa = new AtomicDoubleArray(0);
    assertEquals(0, aa.length());
    assertThrows(IndexOutOfBoundsException.class, () -> aa.get(0));
  }