new AbstractBiMap<Integer, String>(
            new IdentityHashMap<Integer, String>(), new IdentityHashMap<String, Integer>()) {};
    bimap.put(1, "one");
    bimap.put(2, "two");
    bimap.put(3, "three");
    Iterator<Integer> iterator = bimap.keySet().iterator();
    iterator.next();
    iterator.next();
    iterator.remove();
    iterator.next();
    iterator.remove();
    assertEquals(1, bimap.size());

    assertMultimapEquals(
        ImmutableListMultimap.of("one", 1, "two", 2, "three", 3), "one", 1, "two", 2, "three", 3);
    assertMultimapEquals(
        ImmutableListMultimap.of("one", 1, "two", 2, "three", 3, "four", 4),
        "one",
        1,
        "two",
        2,
        "three",
        3,
        "four",
        4);
    assertMultimapEquals(

        mapEntry("one", "January"),
        mapEntry("two", "February"),
        mapEntry("three", "March"),
        mapEntry("four", "April"),
        mapEntry("five", "May"));
  }

  @Override
  public SampleElements<String> sampleKeys() {
    return new SampleElements<>("one", "two", "three", "four", "five");
  }

  @Override
  public SampleElements<String> sampleValues() {

        mapEntry("one", "January"),
        mapEntry("two", "February"),
        mapEntry("three", "March"),
        mapEntry("four", "April"),
        mapEntry("five", "May"));
  }

  @Override
  public SampleElements<String> sampleKeys() {
    return new SampleElements<>("one", "two", "three", "four", "five");
  }

  @Override
  public SampleElements<String> sampleValues() {

        mapEntry("one", "January"),
        mapEntry("two", "February"),
        mapEntry("three", "March"),
        mapEntry("four", "April"),
        mapEntry("five", "May"));
  }

  @Override
  public SampleElements<String> sampleKeys() {
    return new SampleElements<>("one", "two", "three", "four", "five");
  }

  @Override
  public SampleElements<String> sampleValues() {

        mapEntry("one", "January"),
        mapEntry("two", "February"),
        mapEntry("three", "March"),
        mapEntry("four", "April"),
        mapEntry("five", "May"));
  }

  @Override
  public SampleElements<String> sampleKeys() {
    return new SampleElements<>("one", "two", "three", "four", "five");
  }

  @Override
  public SampleElements<String> sampleValues() {

    assertMultimapEquals(
        ImmutableSetMultimap.of("one", 1, "two", 2, "three", 3, "four", 4),
        "one",
        1,
        "two",
        2,
        "three",
        3,
        "four",
        4);
    assertMultimapEquals(
        ImmutableSetMultimap.of("one", 1, "two", 2, "three", 3, "four", 4, "five", 5),
        "one",

     */
    @Test
    public void testPutAll() throws Exception {
        final Map<String, String> m = new HashMap<String, String>();
        m.put("three", "3");
        m.put("four", "4");
        map.putAll(m);
        assertThat(map.get("THREE"), is("3"));
        assertThat(map.get("FOUR"), is("4"));
        assertThat(map.size(), is(4));
    }

    /**
     * @throws Exception
     */

          +
          // One two byte character and a one byte character
          2 * TWO_BYTE_ROUNDTRIPPABLE_CHARACTERS * ONE_BYTE_ROUNDTRIPPABLE_CHARACTERS
          +
          // Three byte characters
          THREE_BYTE_ROUNDTRIPPABLE_CHARACTERS;

  // 1,048,576 [chars 0x10000L to 0x10FFFF]
  private static final long FOUR_BYTE_ROUNDTRIPPABLE_CHARACTERS = 0x10FFFF - 0x10000L + 1;

    assertMultimapEquals(
        ImmutableSetMultimap.of("one", 1, "two", 2, "three", 3, "four", 4),
        "one",
        1,
        "two",
        2,
        "three",
        3,
        "four",
        4);
    assertMultimapEquals(
        ImmutableSetMultimap.of("one", 1, "two", 2, "three", 3, "four", 4, "five", 5),
        "one",