* dummy version.
   *
   * @throws UnsupportedOperationException always
   * @deprecated <b>Pass a parameter of type {@code Comparable} to use {@link
   *     ImmutableSortedSet#of(Comparable)}.</b>
   */
  @DoNotCall("Pass a parameter of type Comparable")
  @Deprecated
  public static <E> ImmutableSortedSet<E> of(E element) {
    throw new UnsupportedOperationException();
  }

    public void oneArgNullableThrowsNPE(@Nullable String s) {
      checkNotNull(s); // doesn't check if you said you'd accept null, but you don't
    }
  }

  private static final String[] STATIC_ONE_ARG_METHODS_SHOULD_PASS = {
    "staticOneArgCorrectlyThrowsNpe",
    "staticOneArgCheckForNullCorrectlyDoesNotThrowNPE",
    "staticOneArgCheckForNullCorrectlyThrowsOtherThanNPE",
    "staticOneArgCheckForNullThrowsNPE",

    assertEquals(
        "Shouldn't catch any more events when unregistered.", expectedEvents, catcher2.getEvents());
  }

  // NOTE: This test will always pass if register() is thread-safe but may also
  // pass if it isn't, though this is unlikely.
  public void testRegisterThreadSafety() throws Exception {
    List<StringCatcher> catchers = Lists.newCopyOnWriteArrayList();

    assertEquals(
        "Shouldn't catch any more events when unregistered.", expectedEvents, catcher2.getEvents());
  }

  // NOTE: This test will always pass if register() is thread-safe but may also
  // pass if it isn't, though this is unlikely.
  public void testRegisterThreadSafety() throws Exception {
    List<StringCatcher> catchers = Lists.newCopyOnWriteArrayList();

   *
   * <ul>
   *   <li>To output a separate entry for each key-value pair, pass {@code multimap.entries()} to a
   *       {@code MapJoiner} method that accepts entries as input, and receive output of the form
   *       {@code key1=A&key1=B&key2=C}.
   *   <li>To output a single entry for each key, pass {@code multimap.asMap()} to a {@code

     *
     * <p>This method is used when testing iterators without a known ordering. We poll the target
     * iterator's next element and pass it to the reference iterator through this method so it can
     * return the same element. This enables the assertion to pass and the reference iterator to
     * properly update its state.
     */
    void promoteToNext(E e) {
      if (nextElements.remove(e)) {

      fail("expected <" + e.getMessage() + "> to contain <" + message + ">");
    }
  }

  /**
   * Test class with valid equals and hashCode methods. Testers created with instances of this class
   * should always pass.
   */
  private static class ValidTestObject {
    private int aspect1;
    private int aspect2;

    ValidTestObject(int aspect1, int aspect2) {
      this.aspect1 = aspect1;
      this.aspect2 = aspect2;

   *
   * <p>This method is declared to accept any 2 {@code Comparable} objects, even if they are not <a
   * href="https://docs.oracle.com/javase/tutorial/collections/interfaces/order.html">mutually
   * comparable</a>. If you pass objects that are not mutually comparable, this method may throw an
   * exception. (The reason for this decision is lost to time, but the reason <i>might</i> be that

    }
  }

  /*
   * Whenever an implementation uses `instanceof` on a parameter instance, the test has to know that
   * (so much for "black box") and try instances that both do and don't pass the check. The "don't"
   * half of that is more awkward to arrange...
   */
  private static <T> Iterable<T> iterable(final Collection<T> collection) {
    // return collection::iterator;
    return new Iterable<T>() {

  private enum SupplierFunctionImpl implements SupplierFunction<@Nullable Object> {
    INSTANCE;

    // Note: This makes T a "pass-through type"
    @Override
    @CheckForNull
    public Object apply(Supplier<@Nullable Object> input) {
      return input.get();
    }

    @Override
    public String toString() {