* MoreExecutors#newDirectExecutorService} and subject to the same constraints.
   *
   * <p>Although all tasks are immediately executed in the thread that submitted the task, this
   * {@code ExecutorService} imposes a small locking overhead on each task submission in order to
   * implement shutdown and termination behavior.
   *
   * <p>Because of the nature of single-thread execution, the methods {@code scheduleAtFixedRate}

    static {
        // Those two public constants are initialized here, as they need all the private constants
        // above to be initialized first, but the code style imposes the public constants to be
        // defined above the private ones...
        OS_FAMILY = getOsFamily();
        IS_WINDOWS = isFamily(FAMILY_WINDOWS);
    }

    private Os() {}

    /**

   * MoreExecutors#newDirectExecutorService} and subject to the same constraints.
   *
   * <p>Although all tasks are immediately executed in the thread that submitted the task, this
   * {@code ExecutorService} imposes a small locking overhead on each task submission in order to
   * implement shutdown and termination behavior.
   *
   * <p>Because of the nature of single-thread execution, the methods {@code scheduleAtFixedRate}

import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import org.jspecify.annotations.Nullable;

/**
 * Imposes a time limit on method calls.
 *
 * @author Kevin Bourrillion
 * @author Jens Nyman
 * @since 1.0
 */
@DoNotMock("Use FakeTimeLimiter")
@J2ktIncompatible
@GwtIncompatible

    return UsingToStringOrdering.INSTANCE;
  }

  /**
   * Returns an arbitrary ordering over all objects, for which {@code compare(a, b) == 0} implies
   * {@code a == b} (identity equality). There is no meaning whatsoever to the order imposed, but it
   * is constant for the life of the VM.
   *
   * <p>Because the ordering is identity-based, it is not "consistent with {@link

@GwtCompatible
public final class Comparators {
  private Comparators() {}

  /**
   * Returns a new comparator which sorts iterables by comparing corresponding elements pairwise
   * until a nonzero result is found; imposes "dictionary order." If the end of one iterable is
   * reached, but not the other, the shorter iterable is considered to be less than the longer one.

@GwtCompatible
public final class Comparators {
  private Comparators() {}

  /**
   * Returns a new comparator which sorts iterables by comparing corresponding elements pairwise
   * until a nonzero result is found; imposes "dictionary order." If the end of one iterable is
   * reached, but not the other, the shorter iterable is considered to be less than the longer one.

 *   <li>It doesn't propagate exceptions, so apps don't have a way to react to them.
 *   <li>It doesn't interoperate well with RxJava, coroutines, and other more commonly used
 *       alternatives.
 *   <li>It imposes requirements on the lifecycle of its subscribers. For example, if an event
 *       occurs between when one subscriber is removed and the next subscriber is added, the event
 *       is dropped.

     * server processing, and reading the response body. If the call requires redirects or retries
     * all must complete within one timeout period.
     *
     * The default value is 0 which imposes no timeout.
     */
    fun callTimeout(
      timeout: Long,
      unit: TimeUnit,
    ) = apply {
      callTimeout = checkDuration("timeout", timeout, unit)
    }

    /**

== Testing in FIPS 140-2 mode

We have a CI matrix job that periodically runs all our tests with the JVM configured
to be FIPS 140-2 compliant with the use of the BouncyCastle FIPS approved Security Provider.
FIPS 140-2 imposes certain requirements that affect how our tests should be set up or what
can be tested. This section summarizes what one needs to take into consideration so that
tests won't fail when run in fips mode.