Yii ArrayValidator

<?php
/**
 * Original sources and separateParams example:
 * @see http://www.yiiframework.com/extension/array-validator/
 *
 * @author Marco van 't Wout, Tremani 2012
 *
 * Example usage:
 *
 * public function rules() {
 *     return array(
 *         array('numberList', 'ArrayValidator', 'validator'=>'numerical', 'params'=>array(
 *             'integerOnly'=>true, 'allowEmpty'=>false
 *         )),
 *     );
 * }
 */
class ArrayValidator extends CValidator {

    /**
     * @var string name of the validator class (example: 'numerical' or 'CustomValidator')
     */
    public $validator;

    /**
     * @var array parameters passed to the validator class
     */
    public $params;

    /**
     * @var bool use a separate params array depending on array attribute keys
     */
    public $separateParams = false;

    /**
     * @var boolean whether the attribute value can be null or empty. Defaults to true,
     * meaning that if the attribute is empty, it is considered valid.
     */
    public $allowEmpty = true;

    /**
     * @var Object the validator instance
     */
    protected $validatorObject;

    /**
     * Validates the attribute of the object.
     * If there is any error, the error message is added to the object.
     * @param CModel $object the object being validated
     * @param string $attribute the attribute being validated
     */
    protected function validateAttribute($object, $attribute)
    {
        if ($this->isEmpty($object->$attribute)) {
            if ($this->allowEmpty === true) {
                $object->$attribute = null;
                return;
            }
            $this->addError($object, $attribute, Yii::t('', '{attribute} is not allowed to be empty', array('{attribute}'=>$attribute)));
            return;
        }

        if (!is_array($object->$attribute) ) {
            $this->addError($object, $attribute, Yii::t('', 'You are trying to validate a non-array attribute'));
            return;
        }

        // Create validator and set params
        $this->validatorObject = self::createValidator($this->validator, $object, array($attribute));
        if (!$this->separateParams) {
            $this->setValidatorParams($this->params);
        }

        // Loop validator for every array element
        $attributeArray = $object->$attribute; // create copy of attribute array
        foreach($attributeArray as $key => &$value) { // by reference
            $object->$attribute = $value; // temporary store single value in object attribute
            if ($this->separateParams) {
                $this->setValidatorParams($this->params[$key]);
            }
            $this->validatorObject->validate($object);
            $value = $object->$attribute; // put validated value back in attribute array
        }
        $object->$attribute = $attributeArray; // restore attribute array

        // If attribute has errors, show first error
        if ($object->hasErrors($attribute)) {
            $firstError = $object->errors[$attribute][0];
            $object->clearErrors($attribute);
            $object->addError($attribute, Yii::t('', 'At least one element has an error:').' '.$firstError);
        }
    }

    /**
     * Set parameters for validator.
     * @param array $params
     */
    protected function setValidatorParams($params)
    {
        foreach($params as $paramName => $paramValue) {
            $this->validatorObject->$paramName = $paramValue;
        }
    }
}