*/

package com.google.common.collect;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * ImmutableSet implementation backed by a JDK HashSet, used to defend against apparent hash
 * flooding. This implementation is never used on the GWT client side.
 *
 * @author Louis Wasserman
 */

   * PeekingIterator#remove()} removes the same elements as the reference's iterator {@code
   * remove()}.
   */
  private static class PeekingIteratorTester<T extends @Nullable Object> extends IteratorTester<T> {
    private final Iterable<T> master;
    private @Nullable List<T> targetList;

    PeekingIteratorTester(Collection<T> master) {
      super(master.size() + 3, MODIFIABLE, master, IteratorTester.KnownOrder.KNOWN_ORDER);

import com.google.errorprone.annotations.DoNotCall;
import com.google.errorprone.annotations.Immutable;
import java.io.Serializable;
import java.util.Map;
import org.jspecify.annotations.NonNull;
import org.jspecify.annotations.Nullable;

/**
 * A {@link ClassToInstanceMap} whose contents will never change, with many other important
 * properties detailed at {@link ImmutableCollection}.
 *
 * @author Kevin Bourrillion
 * @since 2.0
 */

import java.io.Serializable;
import java.util.Objects;
import org.jspecify.annotations.Nullable;

/**
 * An ordering that orders elements by applying an order to the result of a function on those
 * elements.
 */
@GwtCompatible
final class ByFunctionOrdering<F extends @Nullable Object, T extends @Nullable Object>
    extends Ordering<F> implements Serializable {
  final Function<F, ? extends T> function;

import org.jspecify.annotations.Nullable;

/**
 * Equivalence applied on functional result.
 *
 * @author Bob Lee
 * @since 10.0
 */
@GwtCompatible
final class FunctionalEquivalence<F, T> extends Equivalence<F> implements Serializable {

  @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 0;

  private final Function<? super F, ? extends @Nullable T> function;

// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")
@NullMarked
public class MultimapEqualsTester<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMultimapTester<K, V, Multimap<K, V>> {
  public void testEqualsTrue() {
    new EqualsTester()
        .addEqualityGroup(multimap(), getSubjectGenerator().create(getSampleElements().toArray()))

import java.util.Iterator;
import java.util.NoSuchElementException;
import junit.framework.AssertionFailedError;
import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/** Tests for {@link AbstractSequentialIterator}. */
@GwtCompatible
@NullMarked
public class AbstractSequentialIteratorTest extends TestCase {
  @GwtIncompatible // Too slow
  public void testDoublerExhaustive() {

  public Set<E> edgesConnecting(EndpointPair<N> endpoints) {
    return delegate().edgesConnecting(endpoints);
  }

  @Override
  public @Nullable E edgeConnectingOrNull(N nodeU, N nodeV) {
    return delegate().edgeConnectingOrNull(nodeU, nodeV);
  }

  @Override
  public @Nullable E edgeConnectingOrNull(EndpointPair<N> endpoints) {
    return delegate().edgeConnectingOrNull(endpoints);
  }

  @Override

import com.google.common.annotations.J2ktIncompatible;
import java.io.Serializable;
import java.util.Iterator;
import org.jspecify.annotations.Nullable;

/** An ordering that uses the reverse of a given order. */
@GwtCompatible
final class ReverseOrdering<T extends @Nullable Object> extends Ordering<T>
    implements Serializable {
  final Ordering<? super T> forwardOrder;

  ReverseOrdering(Ordering<? super T> forwardOrder) {

 */
@GwtCompatible
public abstract class AbstractSequentialIterator<T> extends UnmodifiableIterator<T> {
  private @Nullable T nextOrNull;

  /**
   * Creates a new iterator with the given first element, or, if {@code firstOrNull} is null,
   * creates a new empty iterator.
   */
  protected AbstractSequentialIterator(@Nullable T firstOrNull) {
    this.nextOrNull = firstOrNull;
  }

  /**