在error页面加以下代码，之后检查网页源代码就会出现错误信息
(URL,Exception是后台传过来的参数)
<div><div th:utext="'&lt;!--'" th:remove="tag"></div><div th:utext="'Failed Request URL : ' + ${url}" th:remove="tag"></div><div th:utext="'Exception message : ' + ${exception.message}" th:remove="tag"></div><ul th:remove="tag"><li th:each="st : ${exception.stackTrace}" th:remove="tag"><span th:utext="${st}" th:remove="tag"></span></li></ul><div th:utext="'--&gt;'" th:remove="tag"></div>
</div>