* @return The processed configuration value or {@code null} if none.
     * @throws BeanConfigurationException If an error occurred while preprocessing the value.
     */
    Object preprocessValue(String value, Class<?> type) throws BeanConfigurationException;

        public Object evaluate(String expression, Class<?> type) throws ExpressionEvaluationException {
            if (preprocessor != null) {
                try {
                    return preprocessor.preprocessValue(expression, type);
                } catch (BeanConfigurationException e) {
                    throw new ExpressionEvaluationException(e.getMessage(), e);
                }
            }