}
    assertNull(map.get(unmappedKey));
  }

  public void testGetNull() {
    Map<K, V> map = makeEitherMap();
    if (allowsNullKeys) {
      if (allowsNullValues) {
        // TODO: decide what to test here.
      } else {
        assertEquals(map.containsKey(null), map.get(null) != null);
      }
    } else {
      try {
        map.get(null);
      } catch (NullPointerException optional) {

   * because caller has previously checked that guardToSkip.isSatisfied() returned false. An
   * optimization for the case that guardToSkip.isSatisfied() may be expensive.
   *
   * <p>We decided against using this method, since in practice, isSatisfied() is likely to be very
   * cheap (typically one field read). Resurrect this method if you find that not to be true.
   */
  //   @GuardedBy("lock")

import com.google.common.primitives.UnsignedLongs;
import java.math.BigInteger;
import java.math.RoundingMode;

/**
 * A class for arithmetic on values of type {@code long}. Where possible, methods are defined and
 * named analogously to their {@code BigInteger} counterparts.
 *
 * <p>The implementations of many methods in this class are based on material from Henry S. Warren,
 * Jr.'s <i>Hacker's Delight</i>, (Addison Wesley, 2002).

       * template to be null (though we do handle that case gracefully at runtime). I've left this
       * one as it is because one of our users has defined a wrapper API around Preconditions,
       * declaring a checkState method that accepts a possibly null template. So we'd need to update
       * that user first.
       */
      @CheckForNull String errorMessageTemplate,

 *       are called <i>cryptographic hash functions</i>. But, whenever it is learned that either of
 *       these feats has become computationally feasible, the function is deemed "broken" and should
 *       no longer be used for secure purposes. (This is the likely eventual fate of <i>all</i>
 *       cryptographic hashes.)

import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Use this to meta-annotate {@code XxxFeature.Require} annotations, so that those annotations can
 * be used to decide whether to apply a test to a given class-under-test.
 *
 * <p>This is needed because annotations can't implement interfaces, which is also why reflection is
 * used to extract values from the properties of the various annotations.

 * specified the JVM flag {@code -XX:+DisableExplicitGC}. But in practice, it works very well for
 * ordinary tests.
 *
 * <p>Failure of the expected event to occur within an implementation-defined "reasonable" time
 * period or an interrupt while waiting for the expected event will result in a {@link
 * RuntimeException}.
 *
 * <p>Here's an example that tests a {@code finalize} method:
 *
 * <pre>{@code

import java.lang.annotation.RetentionPolicy;
import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.SortedSet;

/**
 * Optional features of classes derived from {@code Collection}.
 *
 * @author George van den Driessche
 */
@SuppressWarnings("rawtypes") // maybe avoidable if we rework the whole package?
@GwtCompatible

    assertThat(network.edges()).containsExactly("p", "i", "e").inOrder();
    assertThat(network.nodeOrder()).isEqualTo(unordered());
    assertThat(network.nodes()).containsExactly(4, 1, 3);
  }

  // Sorting of user-defined classes

  @Test
  public void customComparator() {
    Comparator<NonComparableSuperClass> comparator =
        new Comparator<NonComparableSuperClass>() {
          @Override

   * us to the point of the next scheduling time, since we always maintain that. And what we mean by
   * "an unused RateLimiter" is also defined by that notion: when we observe that the
   * "expected arrival time of the next request" is actually in the past, then the difference (now -