public static Class<?> getPropertyType(Class<?> beanClass, String propertyName) {
        BeanMate beanMate = getBeanMate(beanClass);
        Method getter = beanMate.getterMap.get(propertyName);
        if (getter != null) {
            return getter.getReturnType();
        }
        Method setter = beanMate.setterMap.get(propertyName);
        if (setter != null) {
            return setter.getParameterTypes()[0];
        }
        return null;
    }