*/
  @CanIgnoreReturnValue
  public long getAndIncrement(K key) {
    return getAndAdd(key, 1);
  }

  /**
   * Decrements by one the value currently associated with {@code key}, and returns the old value.
   */
  @CanIgnoreReturnValue
  public long getAndDecrement(K key) {
    return getAndAdd(key, -1);
  }

  /**

        prev = x;
      }
    }
  }

  /** getAndAdd returns previous value and adds given value */
  public void testGetAndAdd() {
    AtomicDoubleArray aa = new AtomicDoubleArray(SIZE);
    for (int i : new int[] {0, SIZE - 1}) {
      for (double x : VALUES) {
        for (double y : VALUES) {
          aa.set(i, x);
          double z = aa.getAndAdd(i, y);
          assertBitEquals(x, z);

   *
   * @param i the index
   * @param delta the value to add
   * @return the previous value
   */
  @CanIgnoreReturnValue
  public final double getAndAdd(int i, double delta) {
    return getAndAccumulate(i, delta, Double::sum);
  }

  /**
   * Atomically adds the given value to the element at index {@code i}.
   *
   * @param i the index