import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@code Maps}.
 *
 * @author Kevin Bourrillion
 * @author Mike Bostock
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
@SuppressWarnings("JUnitIncompatibleType") // Many intentional violations here.
public class MapsTest extends TestCase {

 * methods or inner class constructors, the created object uses itself as the synchronization mutex.
 *
 * <p>This class should be used by other collection classes only.
 *
 * @author Mike Bostock
 * @author Jared Levy
 */
@J2ktIncompatible
@GwtCompatible
/*
 * I have decided not to bother adding @ParametricNullness annotations in this class. Adding them is

 * methods or inner class constructors, the created object uses itself as the synchronization mutex.
 *
 * <p>This class should be used by other collection classes only.
 *
 * @author Mike Bostock
 * @author Jared Levy
 */
@J2ktIncompatible
@GwtCompatible
/*
 * I have decided not to bother adding @ParametricNullness annotations in this class. Adding them is

import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@code Maps}.
 *
 * @author Kevin Bourrillion
 * @author Mike Bostock
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
@SuppressWarnings("JUnitIncompatibleType") // Many intentional violations here.
public class MapsTest extends TestCase {

 * "https://github.com/google/guava/wiki/CollectionUtilitiesExplained#multimaps">{@code
 * Multimaps}</a>.
 *
 * @author Jared Levy
 * @author Robert Konigsberg
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
public final class Multimaps {
  private Multimaps() {}

  /**