/* Test that it can be empty. */
    EnumBiMap<Currency, Country> emptyBimap = EnumBiMap.create(Currency.class, Country.class);
    EnumBiMap<Currency, Country> bimap3 = EnumBiMap.create(emptyBimap);
    assertEquals(bimap3, emptyBimap);
  }

  @GwtIncompatible // keyType
  public void testKeyType() {
    EnumBiMap<Currency, Country> bimap = EnumBiMap.create(Currency.class, Country.class);