* inputs' {@link Comparable#compareTo compareTo} and {@link Comparator#compare compare} methods as
 * soon as one of them returns a nonzero result. This optimization is typically important only in
 * the presence of expensive {@code compareTo} and {@code compare} implementations.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/CommonObjectUtilitiesExplained#comparecompareto">{@code

 * of the <i>next</i> request. I.e., if an expensive task arrives at an idle RateLimiter, it will be
 * granted immediately, but it is the <i>next</i> request that will experience extra throttling,
 * thus paying for the cost of the expensive task.
 *
 * @author Dimitris Andreou
 * @since 13.0
 */

   * the request has become less ready for future requests", i.e. its caches become stale, and
   * requests become more likely to trigger expensive operations (a more extreme case of this
   * example is when a server has just booted, and it is mostly busy with getting itself up to
   * speed).
   *

// simply converts positional arguments to NewReader() into a
// more flexible way to provide optional inputs. This is currently
// used by the FanOut API call mostly to disable expensive md5sum
// calculation repeatedly under hash.Reader.
type Options struct {
	MD5Hex     string
	SHA256Hex  string
	Size       int64
	ActualSize int64
	DisableMD5 bool
	ForceMD5   []byte
}

   * [logCloseableLeak].
   */
  open fun getStackTraceForCloseable(closer: String): Any? {
    return when {
      logger.isLoggable(Level.FINE) -> Throwable(closer) // These are expensive to allocate.
      else -> null
    }
  }

  open fun logCloseableLeak(
    message: String,
    stackTrace: Any?,
  ) {
    var logMessage = message
    if (stackTrace == null) {

      }
    } else {
      /*
       * We'll call the user callback or collect the values only when all inputs complete,
       * regardless of whether some failed. This lets us avoid calling expensive methods like
       * Future.get() when we don't need to (specifically, for whenAllComplete().call*()), and it
       * lets all futures share the same listener.
       *

    CountingRemovalListener<Integer, Integer> removalListener = countingRemovalListener();
    IdentityLoader<Integer> loader = identityLoader();

    // Even numbers are free, odd are too expensive
    Weigher<Integer, Integer> evensOnly =
        new Weigher<Integer, Integer>() {
          @Override
          public int weigh(Integer k, Integer v) {
            return k % 2;
          }
        };

      //
      // We use two volatile reads. We could reduce this to one by
      // putting our fields into a holder class, but (at least on x86)
      // the extra memory consumption and indirection are more
      // expensive than the extra volatile reads.
      long nanos = expirationNanos;
      long now = System.nanoTime();
      if (nanos == 0 || now - nanos >= 0) {
        synchronized (this) {

    CountingRemovalListener<Integer, Integer> removalListener = countingRemovalListener();
    IdentityLoader<Integer> loader = identityLoader();

    // Even numbers are free, odd are too expensive
    Weigher<Integer, Integer> evensOnly =
        new Weigher<Integer, Integer>() {
          @Override
          public int weigh(Integer k, Integer v) {
            return k % 2;
          }
        };

    testBytes(3, EXPECTED_THREE_BYTE_ROUNDTRIPPABLE_COUNT);
  }

  /**
   * Tests that round tripping of a sample of four byte permutations work. All permutations are
   * prohibitively expensive to test for automated runs. This method tests specific four-byte cases.
   */
  public void testIsWellFormed_4BytesSamples() {
    // Valid 4 byte.
    assertWellFormed(0xF0, 0xA4, 0xAD, 0xA2);
    // Bad trailing bytes