public void testCreate() {
    EnumBiMap<Currency, Country> bimap = EnumBiMap.create(Currency.class, Country.class);
    assertTrue(bimap.isEmpty());
    assertEquals("{}", bimap.toString());
    assertEquals(HashBiMap.create(), bimap);
    bimap.put(Currency.DOLLAR, Country.CANADA);
    assertEquals(Country.CANADA, bimap.get(Currency.DOLLAR));
    assertEquals(Currency.DOLLAR, bimap.inverse().get(Country.CANADA));
  }

@ElementTypesAreNonnullByDefault
public abstract class AbstractBiMapTester<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMapTester<K, V> {

  @Override
  protected BiMap<K, V> getMap() {
    return (BiMap<K, V>) super.getMap();
  }

  static <K extends @Nullable Object, V extends @Nullable Object> Entry<V, K> reverseEntry(
      Entry<K, V> entry) {
    return mapEntry(entry.getValue(), entry.getKey());
  }

    getMap().forcePut(null, v1());

    expectContents(mapEntry((K) null, v1()));

    assertFalse(getMap().containsValue(v0()));

    assertTrue(getMap().containsValue(v1()));
    assertTrue(getMap().inverse().containsKey(v1()));
    assertNull(getMap().inverse().get(v1()));
    assertEquals(v1(), getMap().get(null));
    assertEquals(1, getMap().size());
  }

@ElementTypesAreNonnullByDefault
public abstract class AbstractBiMapTester<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMapTester<K, V> {

  @Override
  protected BiMap<K, V> getMap() {
    return (BiMap<K, V>) super.getMap();
  }

  static <K extends @Nullable Object, V extends @Nullable Object> Entry<V, K> reverseEntry(
      Entry<K, V> entry) {
    return mapEntry(entry.getValue(), entry.getKey());
  }

      ImmutableBiMap<K, V> bimap = (ImmutableBiMap<K, V>) map;
      // TODO(lowasser): if we need to make a copy of a BiMap because the
      // forward map is a view, don't make a copy of the non-view delegate map
      if (!bimap.isPartialView()) {
        return bimap;
      }
    }
    return copyOf(map.entrySet());
  }

  /**

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.BiMap;
import com.google.common.collect.testing.SampleElements;
import java.util.List;
import java.util.Map.Entry;

/**
 * Implementation helper for {@link TestBiMapGenerator} for use with bimaps of strings.
 *
 * @author Chris Povirk
 * @author Jared Levy
 * @author George van den Driessche

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.BiMap;
import com.google.common.collect.testing.SampleElements;
import java.util.List;
import java.util.Map.Entry;

/**
 * Implementation helper for {@link TestBiMapGenerator} for use with bimaps of strings.
 *
 * @author Chris Povirk
 * @author Jared Levy
 * @author George van den Driessche

      implements TestMapGenerator<K, V>, DerivedGenerator {

    private final OneSizeTestContainerGenerator<BiMap<K, V>, Entry<K, V>> generator;

    public MapGenerator(
        OneSizeTestContainerGenerator<BiMap<K, V>, Entry<K, V>> oneSizeTestContainerGenerator) {
      this.generator = oneSizeTestContainerGenerator;
    }

    @Override

  }

  // BiMap-specific tests

  @SuppressWarnings("DoNotCall")
  public void testForcePut() {
    BiMap<String, Integer> bimap = ImmutableBiMap.copyOf(ImmutableMap.of("one", 1, "two", 2));
    assertThrows(UnsupportedOperationException.class, () -> bimap.forcePut("three", 3));
  }

  public void testKeySet() {
    ImmutableBiMap<String, Integer> bimap =

      implements TestMapGenerator<K, V>, DerivedGenerator {

    private final OneSizeTestContainerGenerator<BiMap<K, V>, Entry<K, V>> generator;

    public MapGenerator(
        OneSizeTestContainerGenerator<BiMap<K, V>, Entry<K, V>> oneSizeTestContainerGenerator) {
      this.generator = oneSizeTestContainerGenerator;
    }

    @Override