*
 * @author Ben Yu
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
public final class Defaults {
  private Defaults() {}

  private static final Double DOUBLE_DEFAULT = 0d;
  private static final Float FLOAT_DEFAULT = 0f;

  /**
   * Returns the default value of {@code type} as defined by JLS --- {@code 0} for numbers, {@code

   * Futures#addCallback addCallback()}.
   *
   * <p>Memory consistency effects: Actions in a thread prior to adding a listener <a
   * href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-17.html#jls-17.4.5">
   * <i>happen-before</i></a> its execution begins, perhaps in another thread.
   *
   * <p>Guava implementations of {@code ListenableFuture} promptly release references to listeners

   * Futures#addCallback addCallback()}.
   *
   * <p>Memory consistency effects: Actions in a thread prior to adding a listener <a
   * href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-17.html#jls-17.4.5">
   * <i>happen-before</i></a> its execution begins, perhaps in another thread.
   *
   * <p>Guava implementations of {@code ListenableFuture} promptly release references to listeners

    return subtype;
  }

  /**
   * Returns true if this type is a supertype of the given {@code type}. "Supertype" is defined
   * according to <a
   * href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-4.html#jls-4.5.1">the rules for
   * type arguments</a> introduced with Java generics.
   *
   * @since 19.0
   */
  public final boolean isSupertypeOf(TypeToken<?> type) {
    return type.isSubtypeOf(getType());

  // but essentially each line will be a call to a Preconditions method that, but for a documented
  // change would be a compiler error.
  // See https://docs.oracle.com/javase/specs/jls/se25/html/jls-15.html#jls-15.12.2 for the spec on
  // how javac selects overloads
  @SuppressWarnings("null")
  public void overloadSelection() {
    Boolean boxedBoolean = null;
    boolean aBoolean = true;

  // but essentially each line will be a call to a Preconditions method that, but for a documented
  // change would be a compiler error.
  // See https://docs.oracle.com/javase/specs/jls/se25/html/jls-15.html#jls-15.12.2 for the spec on
  // how javac selects overloads
  @SuppressWarnings("null")
  public void overloadSelection() {
    Boolean boxedBoolean = null;
    boolean aBoolean = true;

   * mod(-1, 4) == 3
   * mod(-8, 4) == 0
   * mod(8, 4) == 0
   * }
   *
   * @throws ArithmeticException if {@code m <= 0}
   * @see <a href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-15.html#jls-15.17.3">
   *     Remainder Operator</a>
   */
  public static int mod(int x, int m) {
    if (m <= 0) {
      throw new ArithmeticException("Modulus " + m + " must be > 0");
    }

   * mod(-1, 4) == 3
   * mod(-8, 4) == 0
   * mod(8, 4) == 0
   * }
   *
   * @throws ArithmeticException if {@code m <= 0}
   * @see <a href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-15.html#jls-15.17.3">
   *     Remainder Operator</a>
   */
  @GwtIncompatible // TODO
  public static int mod(long x, int m) {
    // Cast is safe because the result is guaranteed in the range [0, m)

   * returns a {@link FluentIterable} of elements of an anonymous type whose supertypes are the <a
   * href="https://docs.oracle.com/javase/specs/jls/se25/html/jls-4.html#jls-4.9">intersection</a>
   * of the supertypes of {@code A} and the supertypes of {@code B}.
   */
  public void testConcatIntersectionType() {
    Iterable<A> aIterable = ImmutableList.of();