assertEquals("dollar", bimap2.get(Currency.DOLLAR));
    assertEquals(bimap1, bimap2);
    bimap2.inverse().put("franc", Currency.FRANC);
    assertEquals("franc", bimap2.get(Currency.FRANC));
    assertNull(bimap1.get(Currency.FRANC));
    assertFalse(bimap2.equals(bimap1));

    /* Test that it can be empty. */

  public void testMapConstructor() {
    /* Test with non-empty Map. */
    Map<String, String> map =
        ImmutableMap.of(
            "canada", "dollar",
            "chile", "peso",
            "switzerland", "franc");
    HashBiMap<String, String> bimap = HashBiMap.create(map);
    assertEquals("dollar", bimap.get("canada"));
    assertEquals("canada", bimap.inverse().get("dollar"));
  }

  private static final int N = 1000;