return new AbstractSet<Entry<K, V>>() {
      private Set<Entry<K, V>> delegate() {
        return delegate.entrySet();
      }

      @Override
      public boolean contains(Object object) {
        try {
          return delegate().contains(object);
        } catch (NullPointerException | ClassCastException e) {
          return false;
        }
      }

      @Override

    return new AbstractSet<Entry<K, V>>() {
      private Set<Entry<K, V>> delegate() {
        return delegate.entrySet();
      }

      @Override
      public boolean contains(Object object) {
        try {
          return delegate().contains(object);
        } catch (NullPointerException | ClassCastException e) {
          return false;
        }
      }

      @Override

    @Override
    public void clear() {
      standardClear();
    }

    @Override
    public int count(Object element) {
      return standardCount(element);
    }

    @Override
    public boolean contains(Object object) {
      return standardContains(object);
    }

    @Override
    public boolean containsAll(Collection<?> collection) {
      return standardContainsAll(collection);
    }

    @Override

  }

  public void test_contains_nonnull_yes() {
    Iterator<@Nullable String> set = Arrays.<@Nullable String>asList("a", null, "b").iterator();
    assertTrue(Iterators.contains(set, "b"));
  }

  public void test_contains_nonnull_no() {
    Iterator<String> set = asList("a", "b").iterator();
    assertFalse(Iterators.contains(set, "c"));
  }

  public void test_contains_null_yes() {

   * keys and values are the result of applying the provided mapping functions to the input
   * elements. The generated map is sorted by the specified comparator.
   *
   * <p>If the mapped keys contain duplicates (according to the specified comparator), an {@code
   * IllegalArgumentException} is thrown when the collection operation is performed. (This differs

 * the JDK collection types and the Guava collection types (listed below).
 *
 * <h2>Collection types</h2>
 *
 * <dl>
 *   <dt>{@link Multimap}
 *   <dd>A new type, which is similar to {@link java.util.Map}, but may contain multiple entries
 *       with the same key. Some behaviors of {@link Multimap} are left unspecified and are provided
 *       only by the subtypes mentioned below.
 *   <dt>{@link ListMultimap}

      fail("putAll(containsNullKey) should throw");
    } catch (NullPointerException expected) {
    }
    expectUnchanged();
    expectNullKeyMissingWhenNullKeysUnsupported(
        "Should not contain null key after unsupported putAll(containsNullKey)");
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_VALUES})
  public void testPutAll_nullValueSupported() {
    putAll(containsNullValue);

  SingletonImmutableSet(E element) {
    this.element = Preconditions.checkNotNull(element);
  }

  @Override
  public int size() {
    return 1;
  }

  @Override
  public boolean contains(@CheckForNull Object target) {
    return element.equals(target);
  }

  @Override
  public UnmodifiableIterator<E> iterator() {
    return Iterators.singletonIterator(element);
  }

  @Override

 * specific replacements are to be considered safe and left unescaped or should be escaped in a
 * general way.
 *
 * <p>A good example of usage of this class is for HTML escaping where the replacement array
 * contains information about the named HTML entities such as {@code &amp;} and {@code &quot;} while
 * {@link #escapeUnsafe} is overridden to handle general escaping of the form {@code &#NNNNN;}.
 *

    }
  }

  /** constructor with empty array has size 0 and contains no elements */
  public void testConstructorEmptyArray() {
    AtomicDoubleArray aa = new AtomicDoubleArray(new double[0]);
    assertEquals(0, aa.length());
    assertThrows(IndexOutOfBoundsException.class, () -> aa.get(0));
  }

  /** constructor with length zero has size 0 and contains no elements */
  public void testConstructorZeroLength() {