*
 * <h3>See also</h3>
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/OrderingExplained">{@code Ordering}</a>.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 * @since 2.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class Ordering<T extends @Nullable Object> implements Comparator<T> {
  // Natural order

  private static final Integer I1 = -1;
  private static final Integer I2 = 3;
  private static final String S0 = "3";
  private static final String S1 = "Ninety five";
  private static final String S2 = "44 one million";
  private static final String S3 = "Lowly laundry lefties";
  private static final String S4 = "89273487U#*&#";
  private static final Double D0 = 9.234d;
  private static final Double D1 = -1.2e55;

  @Benchmark

import com.google.common.annotations.J2ktIncompatible;
import java.io.Serializable;
import javax.annotation.CheckForNull;

/**
 * {@code keySet()} implementation for {@link ImmutableMap}.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
final class ImmutableMapKeySet<K, V> extends IndexedImmutableSet<K> {
  private final ImmutableMap<K, V> map;

import com.google.common.primitives.Ints;
import javax.annotation.CheckForNull;

/**
 * Static methods for implementing hash-based collections.
 *
 * @author Kevin Bourrillion
 * @author Jesse Wilson
 * @author Austin Appleby
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class Hashing {
  private Hashing() {}

  /*

import com.google.common.primitives.Ints;
import javax.annotation.CheckForNull;

/**
 * Static methods for implementing hash-based collections.
 *
 * @author Kevin Bourrillion
 * @author Jesse Wilson
 * @author Austin Appleby
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class Hashing {
  private Hashing() {}

  /*

import org.junit.Ignore;

/**
 * A generic JUnit test which tests operations on a SortedSet. Can't be invoked directly; please see
 * {@code SortedSetTestSuiteBuilder}.
 *
 * @author Jesse Wilson
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@ElementTypesAreNonnullByDefault

import java.util.function.Consumer;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * {@code entrySet()} implementation for {@link ImmutableMap}.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
abstract class ImmutableMapEntrySet<K, V> extends ImmutableSet.CachingAsList<Entry<K, V>> {

import java.util.Map.Entry;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * {@code entrySet()} implementation for {@link ImmutableMap}.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
abstract class ImmutableMapEntrySet<K, V> extends ImmutableSet<Entry<K, V>> {

import java.util.SortedMap;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests operations on a SortedMap. Can't be invoked directly; please see
 * {@code SortedMapTestSuiteBuilder}.
 *
 * @author Jesse Wilson
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
public class SortedMapNavigationTester<K, V> extends AbstractMapTester<K, V> {

import java.util.TreeSet;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests operations on a NavigableSet. Can't be invoked directly; please
 * see {@code NavigableSetTestSuiteBuilder}.
 *
 * @author Jesse Wilson
 * @author Louis Wasserman
 */
@GwtIncompatible
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
public class NavigableSetNavigationTester<E> extends AbstractSetTester<E> {