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.jspecify.annotations.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 {

import com.google.common.annotations.GwtCompatible;
import com.google.common.primitives.Booleans;
import com.google.errorprone.annotations.InlineMe;
import java.util.Comparator;
import org.jspecify.annotations.Nullable;

/**
 * A utility for performing a chained comparison statement. <b>Note:</b> Java 8+ users should
 * generally prefer the methods in {@link Comparator}; see <a href="#java8">below</a>.
 *

import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.lang.reflect.WildcardType;
import java.util.HashSet;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * Based on what a {@link Type} is, dispatch it to the corresponding {@code visit*} method. By
 * default, no recursion is done for type arguments or type bounds. But subclasses can opt to do

import com.google.common.base.Preconditions;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.nio.ByteBuffer;
import java.nio.charset.Charset;
import org.jspecify.annotations.Nullable;

/**
 * An abstract implementation of {@link Hasher}, which only requires subtypes to implement {@link
 * #putByte}. Subtypes may provide more efficient implementations, however.
 *
 * @author Dimitris Andreou
 */

import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/** Replacements for JUnit's {@code assertThrows} that work under GWT/J2CL. */
@GwtCompatible
@NullMarked
final class ReflectionFreeAssertThrows {
  interface ThrowingRunnable {
    void run() throws Throwable;
  }

  interface ThrowingSupplier {
    @Nullable Object get() throws Throwable;
  }

  @CanIgnoreReturnValue

import org.apache.maven.api.RemoteRepository;
import org.apache.maven.api.Session;
import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.Immutable;
import org.apache.maven.api.annotations.Nullable;

/**
 * Base interface for service requests that involve remote repository operations.
 * This interface provides common functionality for requests that need to specify

import com.google.common.collect.ImmutableMap;
import java.util.Map;
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ExecutionException;
import org.jspecify.annotations.Nullable;

/**
 * A cache which forwards all its method calls to another cache. Subclasses should override one or
 * more methods to modify the behavior of the backing cache as desired per the <a

import java.util.Iterator;
import java.util.Set;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

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

import com.google.common.collect.testing.features.CollectionFeature;
import java.lang.reflect.Method;
import java.util.Iterator;
import java.util.List;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;
import org.junit.Ignore;

/**
 * Tester to make sure the {@code iterator().remove()} implementation of {@code Multiset} works when
 * there are multiple occurrences of elements.
 *
 * @author Louis Wasserman
 */