assertEquals(comparator, elementSet.comparator());
  }

  public void testNullAcceptingComparator() throws Exception {
    Comparator<@Nullable String> comparator = Ordering.<String>natural().<String>nullsFirst();
    TreeMultiset<@Nullable String> ms = TreeMultiset.create(comparator);

    ms.add("b");
    ms.add(null);
    ms.add("a");
    ms.add("b");
    ms.add(null, 2);

import java.nio.charset.Charset;
import java.util.concurrent.TimeUnit;
import java.util.regex.Pattern;
import junit.framework.AssertionFailedError;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@link ForwardingWrapperTester}. Live in a different package to detect reflection
 * access issues, if any.
 *
 * @author Ben Yu
 */
public class ForwardingWrapperTesterTest extends TestCase {

                    "kotlin/com/example/Source.kt",
                    """
                    package com.example

                    import org.gradle.api.Incubating
                    import javax.annotation.Nullable

                    $v1
                    """
                )
            },
            v2 = {
                withFile(
                    "kotlin/com/example/Source.kt",

import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.Immutable;
import org.apache.maven.api.annotations.Nonnull;
import org.apache.maven.api.annotations.Nullable;

/**
 * Describes a problem that was encountered during project building. A problem can either be an exception that was
 * thrown or a simple string message. In addition, a problem carries a hint about its source.
 *

import java.util.Collection;
import java.util.List;
import java.util.SortedSet;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@code ForwardingSortedSet}.
 *
 * @author Louis Wasserman
 */
public class ForwardingSortedSetTest extends TestCase {

import java.util.Collection;
import java.util.Set;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@code ForwardingSet}.
 *
 * @author Robert Konigsberg
 * @author Louis Wasserman
 */
public class ForwardingSetTest extends TestCase {

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

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

import com.google.common.annotations.GwtCompatible;
import java.util.ListIterator;
import java.util.NoSuchElementException;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * This class provides a skeletal implementation of the {@link ListIterator} interface across a
 * fixed number of elements that may be retrieved by position. It does not support {@link #remove},

import java.util.Collection;
import java.util.Iterator;
import java.util.Set;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@link ForwardingMultiset}.
 *
 * @author Hayward Chan
 * @author Louis Wasserman
 */
public class ForwardingMultisetTest extends TestCase {

    E[] castedArray = (E[]) array;
    return Arrays.asList(castedArray);
  }

  @Override
  public int indexOf(@Nullable Object object) {
    return (object == null) ? -1 : Lists.indexOfImpl(this, object);
  }

  @Override
  public int lastIndexOf(@Nullable Object object) {
    return (object == null) ? -1 : Lists.lastIndexOfImpl(this, object);
  }