* https://lauri.võsandi.com/2017/03/yubikey-for-ssh-auth.html
 *
 * Using PKCS11 support in the JDK.
 * https://tersesystems.com/blog/2018/09/08/keymanagers-and-keystores/
 *
 * Install OpenSC separately. On a mac `brew cast install opensc`.
 */
@SuppressSignatureCheck
class YubikeyClientAuth {
  fun run() {
    // The typical PKCS11 slot, may vary with different hardware.
    val slot = 0

    @ParametricNullness
    public V apply(@ParametricNullness K key) {
      V result = map.get(key);
      checkArgument(result != null || map.containsKey(key), "Key '%s' not present in map", key);
      // The unchecked cast is safe because of the containsKey check.
      return uncheckedCastNullableTToT(result);
    }

    @Override
    public boolean equals(@Nullable Object o) {
      if (o instanceof FunctionForMapNoDefault) {

     * class could be unloaded after the above call to `getEnumConstants` but before we call
     * `get()`, but that is vanishingly unlikely.
     */
    return ref == null ? Optional.absent() : Optional.fromNullable(enumClass.cast(ref.get()));
  }

  static String formatCompact4Digits(double value) {
    return String.format(Locale.ROOT, "%.4g", value);
  }

  static boolean stringIsNullOrEmpty(@Nullable String string) {

import junit.framework.TestSuite;
import org.jspecify.annotations.NullUnmarked;

/**
 * Test suite covering {@link Ints#asList(int[])}.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@SuppressWarnings("cast") // redundant casts are intentional and harmless
@NullUnmarked
@AndroidIncompatible // test-suite builders
public class IntArrayAsListTest extends TestCase {

  private static List<Integer> asList(Integer[] values) {

        .Builder()
        .addUnsafeNonAscii("header1", "valué1")
        .build()
    assertThat(headers.toString()).isEqualTo("header1: valué1\n")
  }

  // Fails on JS, ClassCastException: Illegal cast
  @Test fun ofMapThrowsOnNull() {
    assertFailsWith<NullPointerException> {
      (mapOf("User-Agent" to null) as Map<String, String>).toHeaders()
    }
  }

  @Test fun toMultimapGroupsHeaders() {

                return entry.getValue().get(columnKey);
              }

              @Override
              public V setValue(V value) {
                /*
                 * The cast is safe because of the containsKey check above. (Well, it's possible for
                 * the map to change between that call and this one. But if that happens, the

      if (!compareAndSet(currentThread, DONE)) {
        waitForInterrupt(currentThread);
      }
      if (run) {
        if (error == null) {
          // The cast is safe because of the `run` and `error` checks.
          afterRanInterruptiblySuccess(uncheckedCastNullableTToT(result));
        } else {
          afterRanInterruptiblyFailure(error);
        }
      }
    }
  }

   * - https://github.com/jspecify/jspecify/issues/65
   *
   * - https://github.com/jspecify/jdk/commit/71d826792b8c7ef95d492c50a274deab938f2552
   */
  /*
   * TODO(cpovirk): Is the unchecked cast avoidable? Would System.arraycopy be similarly fast (if
   * likewise not type-checked)? Could our single caller do something different?
   */
  @SuppressWarnings({"nullness", "unchecked"})

            if (type == null) {
                throw new NullPointerException("type");
            }
            if (type.isInstance(this)) {
                return type.cast(this);
            }
            return null;
        }

        @Override
        public String getUserDomain() {
            return this.domain;
        }

        @Override

      Enum<?> e = (Enum<?>) o;
      int index = e.ordinal();
      return index < enumConstants.length && enumConstants[index] == e;
    }
    return false;
  }

  /**
   * Returns {@code element} cast to {@code E}, if it actually is a nonnull E. Otherwise, throws
   * either a NullPointerException or a ClassCastException as appropriate.
   */
  private void checkIsE(Object element) {
    checkNotNull(element);