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

  public void testInverse() {
    assertEquals(
        ImmutableSetMultimap.<Integer, String>of(),

    Iterator<String> iterator = asList("one", "two", "three", "four", "five").iterator();
    try {
      Iterators.getOnlyElement(iterator);
      fail();
    } catch (IllegalArgumentException expected) {
      assertThat(expected)
          .hasMessageThat()
          .isEqualTo("expected one element but was: <one, two, three, four, five>");
    }
  }

      @Override
      public void run() {
        thirdSignal.countDown();
        result.set(1, cache.getUnchecked(key));
        doneSignal.countDown();
      }
    }.start();

    // give the second get a chance to run; it is okay for this to be racy
    // as the end result should be the same either way
    thirdSignal.await();
    Thread.yield();

    // Expand!

       * lossless. In that case we can compare x to roundArbitrarily using Longs.compare(x,
       * roundArbitrarilyAsLong). The exception is for values where the conversion to double rounds
       * up to give roundArbitrarily equal to 2^63, so the conversion back to long overflows and
       * roundArbitrarilyAsLong is Long.MAX_VALUE. (This is the only way this condition can occur as

            .put("two", 2)
            .put("three", 3)
            .put("four", 4)
            .put("five", 5)
            .build();
    assertMapEquals(map, "one", 1, "two", 2, "three", 3, "four", 4, "five", 5);
    assertMapEquals(map.inverse(), 1, "one", 2, "two", 3, "three", 4, "four", 5, "five");
  }

  @GwtIncompatible
  public void testBuilderExactlySizedReusesArray() {

        "one",
        1,
        "two",
        2,
        "three",
        3,
        "four",
        4,
        "five",
        5);
    assertMapEquals(
        ImmutableMap.of(
            "one", 1,
            "two", 2,
            "three", 3,
            "four", 4,
            "five", 5,
            "six", 6),
        "one",

     * readable name.
     */
    @CanIgnoreReturnValue
    public ToStringHelper addValue(@CheckForNull Object value) {
      return addHolder(value);
    }

    /**
     * Adds an unnamed value to the formatted output.
     *
     * <p>It is strongly encouraged to use {@link #add(String, boolean)} instead and give value a
     * readable name.
     *

        Helpers.mapEntry("three", "March"),
        Helpers.mapEntry("four", "April"),
        Helpers.mapEntry("five", "May"));
  }

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

  @Override
  public SampleElements<String> sampleValues() {

    assertEquals(ImmutableSortedMap.of("four", 4, "one", 3, "three", 5), headMap);
    strings.add("five");
    strings.remove("one");
    assertEquals(ImmutableSortedMap.of("five", 4, "four", 4, "three", 5), headMap);
    assertThat(map.entrySet())
        .containsExactly(
            mapEntry("five", 4), mapEntry("four", 4), mapEntry("three", 5), mapEntry("two", 3))
        .inOrder();
  }

    assertEquals(ImmutableSortedMap.of("four", 4, "one", 3, "three", 5), headMap);
    strings.add("five");
    strings.remove("one");
    assertEquals(ImmutableSortedMap.of("five", 4, "four", 4, "three", 5), headMap);
    assertThat(map.entrySet())
        .containsExactly(
            mapEntry("five", 4), mapEntry("four", 4), mapEntry("three", 5), mapEntry("two", 3))
        .inOrder();
  }