A set of classes to demonstrate polymorphism.

example.php

<?php

require_once 'StudentProfile.php';

$studentProfile = new StudentProfile(
    array(
        'fields' => array(
            ProfileField::factory('Name', 'Buddy'),
            ProfileField::factory('Birth date', '1983/05/05'),
            ProfileField::factory('Graduation date', '2000/01/01'),
        ),
    )
);
echo $studentProfile->format();

IFormatter.php

<?php
/**
 * Formatter interface.
 *
 * A contract to format.
 *
 * @category  Formatter
 * @package   Formatter
 * @author    Saul Martinez <saul@sharkwebintelligence.com>
 * @copyright 2012 Shark Web Intelligence
 * @license   http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
 * @version   1.0
 * @link      http://www.sharkwebintelligence.com
 */
interface IFormatter
{
    /**
     * Object formatting.
     *
     * @return string
     */
    public function format();
}

Profile.php

<?php

require_once 'IFormatter.php';
require_once 'ProfileField.php';

/**
 * Profile.
 *
 * Profile representation.
 *
 * @category  Formatter
 * @package   Profile
 * @author    Saul Martinez <saul@sharkwebintelligence.com>
 * @copyright 2012 Shark Web Intelligence
 * @license   http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
 * @version   1.0
 * @link      http://www.sharkwebintelligence.com
 */
abstract class Profile implements IFormatter
{
    /**
     * @var array $fields Profile fields.
     */
    public $fields;

    /**
     * Constructor.
     *
     * - Set options.
     *
     * @param array $options Profile options.
     */
    public function __construct($options)
    {
        if (is_array($options)) {
            $this->setOptions($options);
        }
    }

    /**
     * Format implementation.
     *
     * @return string
     */
    public function format()
    {
        $output = '';
        foreach ($this->getFields() as $field) {
            $output .= $field;
        }
        return $output;
    }

    /**
     * Adds a field to the fields list.
     *
     * @param ProfileField $field Field to add.
     *
     * @return Profile Provides a fluent interface.
     */
    public function addField(ProfileField $field)
    {
        $this->fields[] = $field;
        return $this;
    }

    /**
     * Set profile fields.
     *
     * @param array $fields Profile fields.
     *
     * @return Profile Provides a fluent interface.
     */
    public function setFields(array $fields)
    {
        $this->fields = $fields;
        return $this;
    }

    /**
     * Get profile fields.
     *
     * @return array
     */
    public function getFields()
    {
        return $this->fields;
    }

    /**
     * Set profile options.
     *
     * @param array $options Profile options.
     *
     * @return Profile Provides a fluent interface.
     */
    public function setOptions(array $options)
    {
        $methods = get_class_methods($this);
        foreach ($options as $name => $value) {
            $method = 'set' . ucfirst($name);
            if (in_array($method, $methods)) {
                $this->$method($value);
            }
        }
        return $this;
    }
}

ProfileField.php

<?php

require_once 'IFormatter.php';

/**
 * Profile field.
 *
 * Holds profile properties.
 *
 * @category   Formatter
 * @package    Profile
 * @subpackage Field
 * @author     Saul Martinez <saul@sharkwebintelligence.com>
 * @copyright  2012 Shark Web Intelligence
 * @license    http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
 * @version    1.0
 * @link       http://www.sharkwebintelligence.com
 */
class ProfileField
{
    /**
     * @var string $name Field name.
     */
    public $name;

    /**
     * @var mixed $value Field value.
     */
    public $value;

    /**
     * Factory method to create a profile field.
     *
     * @param string $name  Field name.
     * @param mixed  $value Field value.
     *
     * @return ProfileField
     */
    public static function factory($name, $value)
    {
        $field = new self();
        $field->name = $name;
        $field->value = $value;
        return $field;
    }

    /**
     * Format the profile field.
     *
     * @return string
     */
    public function __toString()
    {
        return $this->name . ': ' . $this->value . PHP_EOL;
    }
}

StudentProfile.php

<?php

require_once 'Profile.php';

/**
 * Student profile.
 *
 * Just a profile sample.
 *
 * @category   Formatter
 * @package    Profile
 * @subpackage Student
 * @author     Saul Martinez <saul@sharkwebintelligence.com>
 * @copyright  2012 Shark Web Intelligence
 * @license    http://www.apache.org/licenses/LICENSE-2.0 Apache License, Version 2.0
 * @version    1.0
 * @link       http://www.sharkwebintelligence.com
 */
class StudentProfile extends Profile
{
}