*
 * <pre>
 * interface Book {...}
 * public class Books {
 *   public static Book hardcover(String title) {...}
 *   public static Book paperback(String title) {...}
 * }
 * </pre>
 *
 * <p>And all the created {@code Book} instances can be tested with:
 *
 * <pre>
 * new ClassSanityTester()
 *     .forAllPublicStaticMethods(Books.class)
 *     .thatReturn(Book.class)

   *       {@link NullPointerException}.
   *   <li>If there is any visible constructor or visible static factory method declared by the
   *       class, all visible instance methods will be checked too using the instance created by
   *       invoking the constructor or static factory method.
   *   <li>If the constructor or factory method used to construct instance takes a parameter that

   * the returned fluent iterable. That is, the iterator skips the first {@code numberToSkip}
   * elements that exist when the iterator is created, not when {@code skip()} is called.
   *
   * <p>The returned fluent iterable's iterator supports {@code remove()} if the {@code Iterator} of

   * the returned fluent iterable. That is, the iterator skips the first {@code numberToSkip}
   * elements that exist when the iterator is created, not when {@code skip()} is called.
   *
   * <p>The returned fluent iterable's iterator supports {@code remove()} if the {@code Iterator} of