Album.php

<?php
// module/Album/src/Album/Model/Album.php:
namespace Album\Model;

use Zend\Form\Annotation as Form;

class Album{
    /**
     * @Form\Required(false)
     * @Form\Attributes({"type":"hidden"})
     */
    public $id;

    /**
     * @Form\Required(true)
     * @Form\Attributes({"type":"text"})
     * @Form\Options({"label":"Artist"})
     * @Form\Filter({"name":"StringTrim"})
     * @Form\Validator({"name":"StringLength", "options":{"min":1, "max":100}})
     */
    public $artist;

    /**
     * @Form\Required(true)
     * @Form\Attributes({"type":"text"})
     * @Form\Options({"label":"Title"})
     * @Form\Filter({"name":"StringTrim"})
     * @Form\Filter({"name":"StripTags"})
     */
    public $title;