expectAdded((E) null);
  }

  @CollectionFeature.Require(value = SUPPORTS_ADD, absent = ALLOWS_NULL_VALUES)
  public void testOffer_nullUnsupported() {
    assertThrows(NullPointerException.class, () -> getQueue().offer(null));
    expectUnchanged();
    expectNullMissingWhenNullUnsupported("Should not contain null after unsupported offer(null)");
  }

        new WrappedHashMapGenerator() {
          @Override
          Map<String, String> wrap(HashMap<String, String> map) {
            if (map.containsKey(null)) {
              throw new NullPointerException();
            }
            return new AbstractMap<String, String>() {
              @Override
              public Set<Entry<String, String>> entrySet() {
                return map.entrySet();

  @CollectionSize.Require(absent = ZERO)
  public void testSetValueNullUnsupported() {
    for (Entry<K, V> entry : getMap().entrySet()) {
      assertThrows(NullPointerException.class, () -> entry.setValue(null));
      expectUnchanged();
    }
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_VALUES})
  @CollectionSize.Require(absent = ZERO)

  @CollectionSize.Require(absent = ZERO)
  public void testCreateWithNull_unsupported() {
    E[] array = createArrayWithNullElement();

    assertThrows(
        NullPointerException.class,
        () -> {
          Object unused = getSubjectGenerator().create(array);
        });
  }

  /**
   * Returns the {@link Method} instance for {@link #testCreateWithNull_unsupported()} so that tests

  }

  @MapFeature.Require(absent = ALLOWS_NULL_KEY_QUERIES)
  public void testGet_nullNotContainedAndUnsupported() {
    try {
      assertNull("get(null) should return null or throw", get(null));
    } catch (NullPointerException tolerated) {
    }
  }

  @MapFeature.Require(ALLOWS_NULL_KEYS)
  @CollectionSize.Require(absent = ZERO)
  public void testGet_nonNullWhenNullContained() {
    initMapWithNullKey();

    private class DnsSystem : Dns {
      override fun lookup(hostname: String): List<InetAddress> {
        try {
          return InetAddress.getAllByName(hostname).toList()
        } catch (e: NullPointerException) {
          throw UnknownHostException("Broken system behaviour for dns lookup of $hostname").apply {
            initCause(e)
          }
        }
      }
    }
  }

/**
 * @author David Beaumont
 */
@GwtCompatible
@NullUnmarked
public class ArrayBasedEscaperMapTest extends TestCase {
  public void testNullMap() {
    assertThrows(NullPointerException.class, () -> ArrayBasedEscaperMap.create(null));
  }

  public void testEmptyMap() {
    Map<Character, String> map = ImmutableMap.of();
    ArrayBasedEscaperMap fem = ArrayBasedEscaperMap.create(map);

   * original interned instance was garbage-collected.
   *
   * <p><b>Warning:</b> do not use with mutable objects.
   *
   * @throws NullPointerException if {@code sample} is null
   */
  E intern(E sample);

      throw new FooException(); // ok, as long as it's not NullPointerException
    }

    public static void staticOneArgNullableCorrectlyThrowsOtherThanNpe(@Nullable String s) {
      throw new FooException(); // ok, as long as it's not NullPointerException
    }

    public static void staticOneArgCheckForNullThrowsNpe(@CheckForNull String s) {

   * @throws NullPointerException if both {@code first} and {@code second} are null
   * @since 18.0 (since 3.0 as {@code Objects.firstNonNull()}).
   */
  public static <T> T firstNonNull(@Nullable T first, @Nullable T second) {
    if (first != null) {
      return first;
    }
    if (second != null) {
      return second;
    }
    throw new NullPointerException("Both parameters are null");
  }

  /**