import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * GWT emulation of {@code SortedMultiset}, with {@code elementSet} reduced to returning a {@code
 * SortedSet} for GWT compatibility.
 *
 * @author Louis Wasserman
 * @since 11.0
 */
@ElementTypesAreNonnullByDefault
public interface SortedMultiset<E extends @Nullable Object> extends Multiset<E>, SortedIterable<E> {

 *
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class ForwardingMapEntry<K extends @Nullable Object, V extends @Nullable Object>
    extends ForwardingObject implements Map.Entry<K, V> {
  // TODO(lowasser): identify places where thread safety is actually lost

  /** Constructor for use by subclasses. */

import com.google.common.annotations.J2ktIncompatible;
import java.util.HashMap;
import java.util.Map;
import java.util.function.BiConsumer;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Implementation of ImmutableMap backed by a JDK HashMap, which has smartness protecting against
 * hash flooding.
 */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault

import org.checkerframework.checker.nullness.qual.Nullable;
import org.junit.Ignore;

/**
 * Superclass for all {@code Multimap} testers.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@ElementTypesAreNonnullByDefault
public abstract class AbstractMultimapTester<

   */
  public static <F extends @Nullable Object, T extends @Nullable Object> Collection<T> transform(
      Collection<F> fromCollection, Function<? super F, T> function) {
    return new TransformedCollection<>(fromCollection, function);
  }

  static class TransformedCollection<F extends @Nullable Object, T extends @Nullable Object>
      extends AbstractCollection<T> {

import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Preconditions;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Implementation of {@link ImmutableSet} with exactly one element.
 *
 * @author Kevin Bourrillion
 * @author Nick Kralevich
 */
@GwtCompatible(serializable = true, emulated = true)

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.Collection;
import org.checkerframework.checker.nullness.qual.Nullable;
import org.junit.Ignore;

/**
 * Base class for collection testers.
 *
 * @param <E> the element type of the collection to be tested.
 * @author Kevin Bourrillion
 */
@GwtCompatible

 */
@GwtCompatible(emulated = true)
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@ElementTypesAreNonnullByDefault
public class MapPutAllTester<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMapTester<K, V> {
  private List<Entry<K, V>> containsNullKey;
  private List<Entry<K, V>> containsNullValue;

  @Override
  public void setUp() throws Exception {

import java.util.List;
import org.checkerframework.checker.nullness.qual.Nullable;
import org.junit.Ignore;

/**
 * Base class for list testers.
 *
 * @author George van den Driessche
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
@Ignore // Affects only Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
public class AbstractListTester<E extends @Nullable Object> extends AbstractCollectionTester<E> {
  /*

    try {
      copyOf((String[]) null);
      fail();
    } catch (NullPointerException expected) {
    }
  }

  public void testCopyOf_arrayContainingOnlyNull() {
    @Nullable String[] array = new @Nullable String[] {null};
    try {
      copyOf((String[]) array);
      fail();
    } catch (NullPointerException expected) {
    }
  }

  public void testCopyOf_collection_empty() {