* size before writing to pre-allocated space (e.g., for memory-mapped files or fixed-size
   * records).
   *
   * @since NEXT
   */
  public long serializedSize() {
    // We return a long (and not an int) because the max serialized size is approximately
    // 17 billion bytes (2^31 * 8 bytes).

    // The serialization header is 6 bytes:
    //   1 byte for the strategy

        long predictedSize = bf.bitSize() / 8 + 6;
        assertThat(bf.serializedSize()).isEqualTo(predictedSize);

        // Serialize and measure actual size
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        bf.writeTo(out);
        int actualSize = out.size();
        assertThat(bf.serializedSize()).isEqualTo(actualSize);

        assertWithMessage(