assertSame(entry.getValue(), cache.asMap().putIfAbsent(entry.getKey(), newValue));
        Object newKey = new Object();
        assertNull(cache.asMap().putIfAbsent(newKey, entry.getValue()));
        // this getUnchecked() call shouldn't be a cache miss; verified below
        assertEquals(entry.getValue(), cache.getUnchecked(entry.getKey()));
        assertEquals(entry.getValue(), cache.getUnchecked(newKey));

    assertEquals(TypeToken.of(String.class), map.entrySet().iterator().next().getKey());
    assertEquals("test", map.entrySet().iterator().next().getValue());
    assertThrows(
        UnsupportedOperationException.class, () -> map.entrySet().iterator().next().setValue(1));
  }

  public void testEntrySetToArrayMutationThrows() {
    map.putInstance(String.class, "test");

          if (entry.getValue().containsKey(columnKey)) {
            @WeakOuter
            class EntryImpl extends AbstractMapEntry<R, V> {
              @Override
              public R getKey() {
                return entry.getKey();
              }

              @Override
              public V getValue() {
                return entry.getValue().get(columnKey);
              }

    assertEquals("bar", entry.getKey());
    assertEquals(1, (int) entry.getValue());
    entry = entries.next();
    assertEquals("foo", entry.getKey());
    assertEquals(2, (int) entry.getValue());
    entry.setValue(4);
    entry = entries.next();
    assertEquals("bar", entry.getKey());
    assertEquals(3, (int) entry.getValue());
    assertFalse(entries.hasNext());
    entries.remove();

  }

  @Override
  @ParametricNullness
  public final K getKey() {
    return key;
  }

  @Override
  @ParametricNullness
  public final V getValue() {
    return value;
  }

  @Override
  @ParametricNullness
  public final V setValue(@ParametricNullness V value) {
    throw new UnsupportedOperationException();
  }

  private static final long serialVersionUID = 0;

          Entry<K, V> e = (Entry<K, V>) o;
          e.setValue(value); // muhahaha!

          return equal(this.getKey(), e.getKey()) && equal(this.getValue(), e.getValue());
        }
        return false;
      }

      @Override
      public int hashCode() {
        K k = getKey();
        V v = getValue();
        return ((k == null) ? 0 : k.hashCode()) ^ ((v == null) ? 0 : v.hashCode());

    }

    @Override
    @ParametricNullness
    public V setValue(@ParametricNullness V value) {
      Map<K, V> delegate = delegateOrNull();
      if (delegate != null) {
        return uncheckedCastNullableTToT(delegate.put(key, value)); // See discussion in getValue().
      }
      updateLastKnownIndex();
      if (lastKnownIndex == -1) {
        put(key, value);

  private final Map<K, V> backingMap;

  /*
   * Per JDK: "the behavior of a map entry is undefined if the backing map has been modified after
   * the entry was returned by the iterator, except through the setValue operation on the map entry"
   * As such, this field must be cleared before every map mutation.
   *
   * Note about volatile: volatile doesn't make it safe to read from a mutable graph in one thread

  @Benchmark
  int getInstance(int reps) throws Exception {
    int retValue = 0;
    for (int i = 0; i < reps; i++) {
      retValue ^= MessageDigest.getInstance(algorithm).getDigestLength();
    }
    return retValue;
  }

  @Benchmark
  int clone(int reps) throws Exception {
    int retValue = 0;
    for (int i = 0; i < reps; i++) {
      retValue ^= ((MessageDigest) md.clone()).getDigestLength();
    }

  }

  protected final V v0() {
    return e0().getValue();
  }

  protected final K k1() {
    return e1().getKey();
  }

  protected final V v1() {
    return e1().getValue();
  }

  protected final K k2() {
    return e2().getKey();
  }

  protected final V v2() {
    return e2().getValue();
  }

  protected final K k3() {
    return e3().getKey();