@GwtCompatible
final class NullnessCasts {
  /**
   * Accepts a {@code @Nullable T} and returns a plain {@code T}, without performing any check that
   * that conversion is safe.
   *
   * <p>This method is intended to help with usages of type parameters that have {@linkplain
   * ParametricNullness parametric nullness}. If a type parameter instead ranges over only non-null

@GwtCompatible
final class NullnessCasts {
  /**
   * Accepts a {@code @Nullable T} and returns a plain {@code T}, without performing any check that
   * that conversion is safe.
   *
   * <p>This method is intended to help with usages of type parameters that have {@linkplain
   * ParametricNullness parametric nullness}. If a type parameter instead ranges over only non-null

          <item index="10" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NullableDecl" />
          <item index="11" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.compatqual.NullableType" />
          <item index="12" class="java.lang.String" itemvalue="org.checkerframework.checker.nullness.qual.Nullable" />

   *
   * @throws NullPointerException if the first element is null; if this is a possibility, use {@code
   *     iterator().next()} or {@link Iterables#getFirst} instead.
   */
  @SuppressWarnings("nullness") // Unsafe, but we can't do much about it now.
  public final Optional<@NonNull E> first() {
    Iterator<E> iterator = getDelegate().iterator();
    return iterator.hasNext() ? Optional.of(iterator.next()) : Optional.absent();

   *
   * @throws NullPointerException if the first element is null; if this is a possibility, use {@code
   *     iterator().next()} or {@link Iterables#getFirst} instead.
   */
  @SuppressWarnings("nullness") // Unsafe, but we can't do much about it now.
  public final Optional<@NonNull E> first() {
    Iterator<E> iterator = getDelegate().iterator();
    return iterator.hasNext() ? Optional.of(iterator.next()) : Optional.absent();

  }

  public void testCallableStartsAfterFirstFutureCompletes() {
    @SuppressWarnings({"unused", "nullness"})
    Future<?> possiblyIgnoredError = serializer.submitAsync(firstCallable, directExecutor());
    TestCallable secondCallable = new TestCallable(Futures.<Void>immediateFuture(null));
    @SuppressWarnings({"unused", "nullness"})
    Future<?> possiblyIgnoredError1 = serializer.submitAsync(secondCallable, directExecutor());

           * themselves null), so we can treat it as a plain `Object[]`.
           */
          @SuppressWarnings("nullness")
          Object[] result = standardToArray();
          return result;
        }

        @Override
        @SuppressWarnings("nullness") // b/192354773 in our checker affects toArray declarations
        public <T extends @Nullable Object> T[] toArray(T[] array) {

    return Arrays.copyOf(empty, length);
  }

  /** Equivalent to Arrays.copyOfRange(source, from, to, arrayOfType.getClass()). */
  /*
   * Arrays are a mess from a nullness perspective, and Class instances for object-array types are
   * even worse. For now, we just suppress and move on with our lives.
   *
   * - https://github.com/jspecify/jspecify/issues/65
   *

           * themselves null), so we can treat it as a plain `Object[]`.
           */
          @SuppressWarnings("nullness")
          Object[] result = standardToArray();
          return result;
        }

        @Override
        @SuppressWarnings("nullness") // b/192354773 in our checker affects toArray declarations
        public <T extends @Nullable Object> T[] toArray(T[] array) {

  }

  @CanIgnoreReturnValue
  @Override
  public @Nullable V replace(K key, V value) {
    return delegate().replace(key, value);
  }

  @CanIgnoreReturnValue
  @Override
  @SuppressWarnings("nullness") // https://github.com/jspecify/jdk/issues/118
  public boolean replace(K key, V oldValue, V newValue) {
    return delegate().replace(key, oldValue, newValue);
  }