public function init()
    {
        parent::init();

        // checks to see if there are duplicate values in the options array
        $options_count = array();
        foreach ($this->getOptions() as $option) {
            $options_count[] = $option->value;
        }

        foreach (array_count_values($options_count) as $count) {
            if ($count > 1) {
                throw new SwatException(
                    sprintf('Duplicate option values found in %s', $this->id)
                );
            }
        }
    }