Optional创建对象

Optional.ofNullable静态方法

public static void main(String[] args) {
    Author author = null;
    Optional<Author> optional = Optional.ofNullable(author);

    optional.ifPresent(au -> System.out.println(au.getName()));
}

Optional作为返回值：

public static void main(String[] args) {
    Optional<Author> author = getAuthor();
    author.ifPresent(a -> System.out.println(a.getName()));
}

private static Optional<Author> getAuthor() {
    //数据初始化
    Author author = new Author(1L, "蒙多", 33, "一个从菜刀中明悟哲理的祖安人", null);

    return Optional.ofNullable(author);
}