BiMap<Integer, String> map = HashBiMap.create();
    map.put(1, "one");
    Set<Entry<Integer, String>> entries = map.entrySet();
    Iterator<Entry<Integer, String>> iterator = entries.iterator();
    Entry<Integer, String> entry = iterator.next();
    entry.setValue("two"); // changes the iterator's current entry value
    assertThat(map.get(1)).isEqualTo("two");

   */
  protected @Nullable Entry<E> standardPollFirstEntry() {
    Iterator<Entry<E>> entryIterator = entrySet().iterator();
    if (!entryIterator.hasNext()) {
      return null;
    }
    Entry<E> entry = entryIterator.next();
    entry = Multisets.immutableEntry(entry.getElement(), entry.getCount());
    entryIterator.remove();
    return entry;
  }

  @Override

  @CollectionSize.Require(absent = ZERO)
  public void testSetValue_valueAbsent() {
    for (Entry<K, V> entry : getMap().entrySet()) {
      if (entry.getKey().equals(k0())) {
        assertEquals("entry.setValue() should return the old value", v0(), entry.setValue(v3()));
      }
    }
    expectReplacement(entry(k0(), v3()));
  }

  @MapFeature.Require(SUPPORTS_PUT)
  @CollectionSize.Require(SEVERAL)

    @SuppressWarnings("unchecked")
    Entry<String, String>[] array = (Entry<String, String>[]) new Entry<?, ?>[entries.length];
    int i = 0;
    for (Object o : entries) {
      @SuppressWarnings("unchecked")
      Entry<String, String> e = (Entry<String, String>) o;
      array[i++] = e;
    }
    return create(array);
  }

  protected abstract BiMap<String, String> create(Entry<String, String>[] entries);

  @Override

    @SuppressWarnings("unchecked")
    Entry<String, String>[] array = (Entry<String, String>[]) new Entry<?, ?>[entries.length];
    int i = 0;
    for (Object o : entries) {
      @SuppressWarnings("unchecked")
      Entry<String, String> e = (Entry<String, String>) o;
      array[i++] = e;
    }
    return create(array);
  }

  protected abstract BiMap<String, String> create(Entry<String, String>[] entries);

  @Override

    @SuppressWarnings("unchecked") // Should get a CCE later if cast is wrong
    Entry<?, Object> entry = (Entry<?, Object>) map.entrySet().toArray(new Entry<?, ?>[0])[0];
    assertEquals(TypeToken.of(String.class), entry.getKey());
    assertEquals("test", entry.getValue());
    assertThrows(UnsupportedOperationException.class, () -> entry.setValue(1));
  }

  public void testPutAndGetInstance() {

    /**
     * construct a single vertex
     */
    public MetadataGraph(MetadataGraphVertex entry) throws MetadataResolutionException {
        checkVertex(entry);
        checkVertices(1);

        entry.setCompareVersion(versionedVertices);
        entry.setCompareScope(scopedVertices);

        vertices.add(entry);
        this.entry = entry;
    }
    // ------------------------------------------------------------------------

    Entry<K, V> entry = cacheEntry; // store local reference for thread-safety

    // Check cache. We use == on purpose because it's cheaper and a cache miss is ok.
    if (entry != null && entry.getKey() == key) {
      return entry.getValue();
    }
    return null;
  }

  void clearCache() {
    cacheEntry = null;
  }

  }

  public void testEmptyRangeSubMultisetSupportingAdd(SortedMultiset<E> multiset) {
    for (Entry<E> entry : asList(a, b, c)) {
      expectAddFailure(multiset, entry);
    }
  }

  private static int totalSize(Iterable<? extends Entry<?>> entries) {
    int sum = 0;
    for (Entry<?> entry : entries) {
      sum += entry.getCount();
    }
    return sum;
  }

  private enum SubMultisetSpec {

  @Override
  public Set<Entry<K, V>> create(Object... elements) {
    Entry<K, V>[] entries = createArray(elements.length);
    arraycopy(elements, 0, entries, 0, elements.length);
    return createFromEntries(entries);
  }

  public abstract Set<Entry<K, V>> createFromEntries(Entry<K, V>[] entries);

  @Override
  @SuppressWarnings("unchecked") // generic arrays make typesafety sad
  public Entry<K, V>[] createArray(int length) {