// Internal helper methods

  /** Circularly increment i. */
  final int inc(int i) {
    return (++i == items.length) ? 0 : i;
  }

  /**
   * Inserts element at current put position, advances, and signals. Call only when occupying
   * monitor.
   */
  private void insert(E x) {
    items[putIndex] = x;
    putIndex = inc(putIndex);
    ++count;
  }

  /**

  // Internal helper methods

  /** Circularly increment i. */
  final int inc(int i) {
    return (++i == items.length) ? 0 : i;
  }

  /**
   * Inserts element at current put position, advances, and signals. Call only when occupying
   * monitor.
   */
  private void insert(E x) {
    items[putIndex] = x;
    putIndex = inc(putIndex);
    ++count;
  }

  /**