java反射取值问题,用于封装公共类

public class UserController {    public static void main(String[] args) {        //对象1        User user = new User();        user.setAge(11);        String value = getValue(user,"age");        System.out.println(value);        //对象2        Order order = new Order();        order.setOrderNo("30320170901400098");        String oValue = getValue(order,"orderNo");        System.out.println(oValue);    }    /**     * 根据key取出object中的值,     * @param object     * @param key     * @return     */    public static String getValue(Object object,String key){        String value="";        try {            if(object!=null){              Field field = object.getClass().getDeclaredField(key);              field.setAccessible(true);              value=(null!=field.get(object)?field.get(object).toString():"");            }        }catch (Exception e){            e.printStackTrace();        }        return value;    }}