SUBMAP,
    DESCENDING;

    @Override
    public Set<Feature<? super @Nullable Void>> getImpliedFeatures() {
      return emptySet();
    }
  }

  /**
   * Creates a suite whose map has some elements filtered out of view.
   *
   * <p>Because the map may be ascending or descending, this test must derive the relative order of
   * these extreme values rather than relying on their regular sort ordering.

import java.time.Duration;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicLong;
import org.jspecify.annotations.NullMarked;

/**
 * A Ticker whose value can be advanced programmatically in test.
 *
 * <p>The ticker can be configured so that the time is incremented whenever {@link #read} is called:
 * see {@link #setAutoIncrementStep}.
 *
 * <p>This class is thread-safe.

      try {
        Method unused = clazz.getDeclaredMethod("writeReplace");
        continue; // It overrides writeReplace, so it's safe.
      } catch (NoSuchMethodException e) {
        // This is a class whose supertypes we want to examine. We'll do that below.
      }
      Optional<Class<?>> supersWithPackagePrivateWriteReplace =
          FluentIterable.from(TypeToken.of(clazz).getTypes())

 * equality for both keys and values. This may not be the desired behavior for map implementations
 * that use non-standard notions of key equality, such as the entry of a {@code SortedMap} whose
 * comparator is not consistent with {@code equals}.
 *
 * <p>The {@code standard} methods are not guaranteed to be thread-safe, even when all of the
 * methods that they depend on are thread-safe.
 *

    SUBMAP,
    DESCENDING;

    @Override
    public Set<Feature<? super @Nullable Void>> getImpliedFeatures() {
      return emptySet();
    }
  }

  /**
   * Creates a suite whose map has some elements filtered out of view.
   *
   * <p>Because the map may be ascending or descending, this test must derive the relative order of
   * these extreme values rather than relying on their regular sort ordering.

   *
   * <p><b>Java 11+ users:</b> use {@link Writer#nullWriter()} instead. Note that the {@link
   * CharStreams} method returns a singleton writer whose {@code close} method has no effect, while
   * the {@link Writer#nullWriter()} method returns a new instance whose methods throw after the
   * instance is {@link Writer#close() closed}.
   *
   * @since 15.0
   */
  public static Writer nullWriter() {

   * never use this method, preferring instead to call {@code requireNonNull} so as to benefit from
   * its runtime check.
   *
   * <p>An example use case for this method is in implementing an {@code Iterator<T>} whose {@code
   * next} field is lazily initialized. The type of that field would be {@code @Nullable T}, and the
   * code would be responsible for populating a "real" {@code T} (which might still be the value

      assertThat(cache.asMap().entrySet()).containsExactly(immutableEntry(key2, value2));
    }
  }

  // fails in Maven with 64-bit JDK: https://github.com/google/guava/issues/1568

  // A simple type whose .toString() will return the same value each time, but without maintaining
  // a strong reference to that value.
  static class Key {
    private final int value;
    private WeakReference<String> toString;

   * never use this method, preferring instead to call {@code requireNonNull} so as to benefit from
   * its runtime check.
   *
   * <p>An example use case for this method is in implementing an {@code Iterator<T>} whose {@code
   * next} field is lazily initialized. The type of that field would be {@code @Nullable T}, and the
   * code would be responsible for populating a "real" {@code T} (which might still be the value

      assertThat(cache.asMap().entrySet()).containsExactly(immutableEntry(key2, value2));
    }
  }

  // fails in Maven with 64-bit JDK: https://github.com/google/guava/issues/1568

  // A simple type whose .toString() will return the same value each time, but without maintaining
  // a strong reference to that value.
  static class Key {
    private final int value;
    private WeakReference<String> toString;