holder.add(1);
    assertEquals(21, holder.get());
  }

  public void testAddAndGet() {
    Count holder = new Count(20);
    assertEquals(21, holder.addAndGet(1));
  }

  public void testGetAndSet() {
    Count holder = new Count(10);
    assertEquals(10, holder.getAndSet(20));
    assertEquals(20, holder.get());
  }

  public void testSet() {
    Count holder = new Count(10);
    holder.set(20);

      while (!at.weakCompareAndSet(prev, x)) {;
      }
      assertBitEquals(x, at.get());
      prev = x;
    }
  }

  /** getAndSet returns previous value and sets to given value */
  public void testGetAndSet() {
    double prev = Math.E;
    AtomicDouble at = new AtomicDouble(prev);
    for (double x : VALUES) {
      assertBitEquals(prev, at.getAndSet(x));
      prev = x;
    }
  }

    holder.add(1);
    assertEquals(21, holder.get());
  }

  public void testAddAndGet() {
    Count holder = new Count(20);
    assertEquals(21, holder.addAndGet(1));
  }

  public void testGetAndSet() {
    Count holder = new Count(10);
    assertEquals(10, holder.getAndSet(20));
    assertEquals(20, holder.get());
  }

  public void testSet() {
    Count holder = new Count(10);
    holder.set(20);