改了一次项目名称，该名称之前运行没有问题，改了之后发生的异常。
1.在首页点击‘系统简介’后无法跳转过去

显示页面空白

2.先点击‘房源展示’，然后再点击‘系统简介’就可以正常跳转过去。

3.控制台报异常，但是代码之前运行的没问题，这里也没改过，只改了项目名称相关的地方。

select distinct(leibie) as ss from xinwengonggao
select * from fangyuanxinxi where fangwuzhaopian<>'' order by id desc
select * from xinwengonggao where leibie='新闻公告' order by id desc
select distinct(leibie) as ss from xinwengonggao
2020-4-24 23:00:59 org.apache.catalina.core.ApplicationContext log
信息: An exception occurred processing JSP page /dx_detail.jsp at line 37

34: <div align="center" style="color:#000000">
35:
36: <%
37: HashMap m = new CommDAO().getmaps("leibie",lb,"dx");
38: %>
39: <table width="1114" height="430" border="0" align="center" cellpadding="0" cellspacing="0" bordercolor="#FA8A89" class="newsline" style="border-collapse:collapse">
40: <tr>

Stacktrace:
select distinct(leibie) as ss from xinwengonggao
select * from fangyuanxinxi where 1=1 order by id desc
select * from fangyuanxinxi where 1=1 order by id desc
select distinct(leibie) as ss from xinwengonggao

4.在首页第一次点击‘新闻公告’会有乱码，再次或者多次点击就显示正常了。

点第一次出现乱码。

之后就正常了。

执行的语句是一样的，但是第一次会有乱码后面则正常。

Stacktrace:
select distinct(leibie) as ss from xinwengonggao
select * from fangyuanxinxi where 1=1 order by id desc
select * from fangyuanxinxi where 1=1 order by id desc
select distinct(leibie) as ss from xinwengonggao
select distinct(leibie) as ss from xinwengonggao
select * from xinwengonggao where leibie='新闻公告' order by id desc
select * from xinwengonggao where leibie='新闻公告' order by id desc
select distinct(leibie) as ss from xinwengonggao
select * from fangyuanxinxi where fangwuzhaopian<>'' order by id desc
select * from xinwengonggao where leibie='新闻公告' order by id desc
select distinct(leibie) as ss from xinwengonggao
select * from xinwengonggao where leibie='?伴????' order by id desc
select * from xinwengonggao where leibie='?伴????' order by id desc
select distinct(leibie) as ss from xinwengonggao
select * from xinwengonggao where leibie='新闻公告' order by id desc
select * from xinwengonggao where leibie='新闻公告' order by id desc

相关代码如下：

<div class="section">
<div class="kcBox clear-fix">
<div class="knowList clear-fix">
<div class="Ttitle">新闻公告<span>News</span>

</div>

<ul class="knowListUl">
<%

for(HashMap map:new CommDAO().select("select * from xinwengonggao where leibie='新闻公告' order by id desc ",1,4)){

%>
<li><a href="gg_detail.jsp?id=<%=map.get("id")%>"><%=Info.ensubStr(map.get("biaoti"),24)%></a><span><%=map.get("addtime").toString().substring(0,10) %></span> </li>
<%
}
%>
<div class="navgrp">
<ul class="nav" id="nav">
<li class="cur"><a href="index.jsp">网站首页</a></li>
<li><a href="dx_detail.jsp?lb=系统简介">系统简介</a> </li>
</li>
<li><a href="fangyuanxinxilisttp.jsp">房源展示</a> </li>
<li><a href="news.jsp?lb=新闻公告">新闻公告</a>
</li>
<li><a href="lyblist.jsp">在线留言</a> </li>
<li><a href="userreg.jsp">用户注册</a>
<li><a href="login.jsp">后台管理</a> </li>
</ul>
</div>
<%@ include file="qttop.jsp"%>
<div class="section ">
<div class="TtitleBox">
<div class="Ttitle"><%=lb%><span>Service items</span>
<div class="Tmore"> </div>
</div>


</div>

<div align="center" style="color:#000000">

<%
HashMap m = new CommDAO().getmaps("leibie",lb,"dx");
%>
<table width="1114" height="430" border="0" align="center" cellpadding="0" cellspacing="0" bordercolor="#FA8A89" class="newsline" style="border-collapse:collapse">
<tr>
<td height="357" align="left"><font color="000000"><%=m.get("content") %></font></td>
</tr>
<tr>
<td height="33" align="right"><input type="button" name="Submit5" value="返回" onClick="javascript:history.back();" ></td>
</tr>
</table>

</div>