}

  @Override
  @CheckForNull
  public Entry<E> firstEntry() {
    return forwardMultiset().lastEntry();
  }

  @Override
  @CheckForNull
  public Entry<E> lastEntry() {
    return forwardMultiset().firstEntry();
  }

  abstract Iterator<Entry<E>> entryIterator();

  @LazyInit @CheckForNull private transient Set<Entry<E>> entrySet;

  @Override
  public Set<Entry<E>> entrySet() {

  }

  @Override
  @CheckForNull
  public Entry<E> firstEntry() {
    return forwardMultiset().lastEntry();
  }

  @Override
  @CheckForNull
  public Entry<E> lastEntry() {
    return forwardMultiset().firstEntry();
  }

  abstract Iterator<Entry<E>> entryIterator();

  @LazyInit @CheckForNull private transient Set<Entry<E>> entrySet;

  @Override
  public Set<Entry<E>> entrySet() {

      BiMap<Country, String> result = EnumHashBiMap.create(Country.class);
      for (Object o : entries) {
        Entry<Country, String> entry = (Entry<Country, String>) o;
        result.put(entry.getKey(), entry.getValue());
      }
      return result;
    }

    @Override
    public SampleElements<Entry<Country, String>> samples() {
      return new SampleElements<>(
          Maps.immutableEntry(Country.CANADA, "DOLLAR"),

    return comparator;
  }

  @Override
  @CheckForNull
  public Entry<E> firstEntry() {
    Iterator<Entry<E>> entryIterator = entryIterator();
    return entryIterator.hasNext() ? entryIterator.next() : null;
  }

  @Override
  @CheckForNull
  public Entry<E> lastEntry() {
    Iterator<Entry<E>> entryIterator = descendingEntryIterator();
    return entryIterator.hasNext() ? entryIterator.next() : null;

                  @Override
                  protected SortedMap<String, String> create(Entry<String, String>[] entries) {
                    NavigableMap<String, String> map = new SafeTreeMap<>(Ordering.natural());
                    for (Entry<String, String> entry : entries) {
                      map.put(entry.getKey(), entry.getValue());
                    }
                    return map;
                  }

    public boolean remove(@CheckForNull Object o) {
      if (o instanceof Entry) {
        Entry<?, ?> entry = (Entry<?, ?>) o;
        if (unfiltered.containsKey(entry.getKey())
            // if this holds, then we know entry.getKey() is a K
            && keyPredicate.apply((K) entry.getKey())) {
          return unfiltered.remove(entry.getKey(), entry.getValue());
        }
      }
      return false;
    }
  }

    public boolean remove(@CheckForNull Object o) {
      if (o instanceof Entry) {
        Entry<?, ?> entry = (Entry<?, ?>) o;
        if (unfiltered.containsKey(entry.getKey())
            // if this holds, then we know entry.getKey() is a K
            && keyPredicate.apply((K) entry.getKey())) {
          return unfiltered.remove(entry.getKey(), entry.getValue());
        }
      }
      return false;
    }
  }

          reverse(samples.e3()),
          reverse(samples.e4()));
    }

    private Entry<V, K> reverse(Entry<K, V> entry) {
      return Helpers.mapEntry(entry.getValue(), entry.getKey());
    }

    @SuppressWarnings("unchecked")
    @Override
    public BiMap<V, K> create(Object... elements) {
      Entry<?, ?>[] entries = new Entry<?, ?>[elements.length];
      for (int i = 0; i < elements.length; i++) {

      for (Entry<AnEnum, String> entry : entries) {
        map.put(entry.getKey(), entry.getValue());
      }
      return ImmutableMap.copyOf(map);
    }

    @Override
    public Iterable<Entry<AnEnum, String>> order(List<Entry<AnEnum, String>> insertionOrder) {
      return new Ordering<Entry<AnEnum, String>>() {

        @Override
        public int compare(Entry<AnEnum, String> left, Entry<AnEnum, String> right) {

  }

  public void testToString() {
    assertEquals("foo=1", entry("foo", 1).toString());
  }

  public void testToStringNull() {
    assertEquals("null=1", entry(NK, 1).toString());
    assertEquals("foo=null", entry("foo", NV).toString());
    assertEquals("null=null", entry(NK, NV).toString());
  }

  public void testEquals() {
    Entry<String, Integer> foo1 = entry("foo", 1);