跳转到jsp后显示不出页面

jsp页面代码有错误，代码贴出来

servlet是这个：package com.icss.oa.zbs.yjsduty.admin;import java.io.IOException;
import java.sql.Connection;
import java.util.ArrayList;
import java.util.List;import javax.servlet.Servlet;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import com.icss.common.log.ConnLog;
import com.icss.j2ee.services.DBConnectionLocator;
import com.icss.j2ee.services.DBConnectionLocatorException;
import com.icss.j2ee.servlet.ServletBase;
import com.icss.j2ee.util.Globals;
import com.icss.oa.zbs.yjsduty.handler.YjsWorkInfoHandler;
/**
* @version 1.0
* @author wangsu
*/
public class YjsDutyTypeManageListServlet extends ServletBase implements Servlet { /**
* @see com.icss.j2ee.servlet.ServletBase#void (javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
*/
public void performTask(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
Connection conn = null;
List mainDutyTypeList = new ArrayList();
try {
ConnLog.open("DutyTypeManageListServlet");
conn = DBConnectionLocator.getInstance().getConnection(Globals.DATASOURCEJNDI);
YjsWorkInfoHandler handler = new YjsWorkInfoHandler(conn); mainDutyTypeList = handler.getMainDutyTypeListByClause("1=1");//取出列表
request.setAttribute("mainDutyTypeList", mainDutyTypeList);
System.out.println("靠谱1");
String msgid = request.getParameter("msgid");
if("1".equals(msgid)){
request.setAttribute("msgid", msgid);
}
this.forward(request, response, "/zbs/yjs_duty/YjsdutyTypeManageList.jsp");
} catch (DBConnectionLocatorException e) {
// TODO 自动生成 catch 块
e.printStackTrace();
} finally {
try {
if (conn != null) {
conn.close();
ConnLog.close("YjsDutyTypeManageListServlet");
}
} catch (Exception e1) {
e1.printStackTrace();
}
}
}}

jsp是这个：<%@ page contentType="text/html; charset=GBK" %>
<%response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0);
%>
<%@ page import="java.util.*" %>
<%@ page import="com.icss.oa.zbs.yjsduty.vo.TbYjsWorkinfotypeVO" %>
<%
List mainDutyTypeList = (List) request.getAttribute("mainDutyTypeList");
String msgid = (String) request.getAttribute("msgid");
%>
<html>
<head>
<title>[值班分类列表1234]</title>
<meta http-equiv="Content-Type" content="text/html; charset=GBK">

<link href="<%=request.getContextPath()%>/Style/css.css" rel="stylesheet" type="text/css" />
<link href="<%=request.getContextPath()%>/Style/css_grey.css" id=homepagestyle rel="stylesheet" type="text/css" />
<style type="text/css">
</style>
<script type="text/javascript" src="<%=request.getContextPath()%>/zbs/include/judge.js"></script>
<SCRIPT src="<%=request.getContextPath()%>/zbs/include/js/common.js"></SCRIPT>
<script language="JavaScript" src="<%=request.getContextPath()%>/zbs/include/formVerify.js"></script>
<script language="JavaScript" src="<%=request.getContextPath()%>/zbs/include/runFormVerify.js"></script>
<script language="JavaScript" src="<%=request.getContextPath()%>/zbs/include/extendString.js"></script>
<script language="JavaScript" src="<%=request.getContextPath()%>/zbs/include/js/calendar.js"></script>
<script language="javascript">

   function _delete(){
if (IsRadioChecked(document.myForm.witid,"请选择要删除的值班分类！")){
if(confirm("您确认要删除所选的值班分类?包含值班记录的分类无法删除!")){
    document.myForm.action="<%=request.getContextPath()%>/servlet/YjsDutyTypeDeleteServlet";
    document.myForm.submit();
    }
    }
   }
   function _modify(id,name,desc){
    document.myForm.modifydutyid.value = id;
    document.myForm.type_name.value = name;
    document.myForm.type_desc.value = desc;
   }
   function _save(a){
   if(_check(document.myForm)){
    document.myForm.action="<%=request.getContextPath()%>/servlet/YjsDutyTypeSaveServlet?add="+a;
    document.myForm.submit();
   }}   function fPopUpCalendarDlg(ctrlobj){
showx = event.screenX - event.offsetX +4 ; // + deltaX;
showy = event.screenY - event.offsetY + 18; // + deltaY;
newWINwidth = 210 + 4 + 18;
retval = window.showModalDialog("<%=request.getContextPath()%>/zbs/include/date.htm", "", "dialogWidth:197px; dialogHeight:210px; dialogLeft:"+showx+"px; dialogTop:"+showy+"px; status:no; directories:yes;scrollbars:no;Resizable=no; "  );
if( retval != null ){
ctrlobj.value = retval;
}
  }
   function _onload(){
   if('1'=='<%=msgid%>'){
   alert("无法删除!请确认此分类下无值班记录!");
   }
   }
</script>
<style type="text/css">
body {
margin-left: 0px;
margin-top: 0px;
margin-right: 0px;
margin-bottom: 0px;
}
</style>
</head>
<BODY text="#000000" leftMargin="0" topMargin="10" onLoad="_onload()">
<form name="myForm" method="post">
<jsp:include page= "/include/top.jsp" />
<input type="hidden" name="modifydutyid">
<table width="983" border="0" align="center" cellpadding="0" cellspacing="0">
<tr><td height="5"></td></tr>
</table>
<table width="983" border="0" align="center" cellpadding="0"
cellspacing="0" class="text">
<tr>
<td bgcolor="#FFFFFF"> </td>
<td valign="top">
<table width="100%" border="0" cellpadding="2" cellspacing="1" class="table_bgcolor">
<tr>
<td width="5%" height="24" class="block_title">
<div align="center"></div>
</td>

<td width="10%" class="block_title">
<div align="center">序号</div>
</td>
<td width="35%" class="block_title">
<div align="center">值班信息分类</div>
</td>
<td width="45%" class="block_title">
<div align="center">说明</div>
</td>
</tr>
<%for(int i=0;i<mainDutyTypeList.size();i++){
TbYjsWorkinfotypeVO vo = (TbYjsWorkinfotypeVO)mainDutyTypeList.get(i);//取出vo（一条记录）
String name = vo.getWitName();
String memo = vo.getWitMemo();
%>
<tr>
<td height="26" bgcolor="#FFFFFF">
<div align="center"><input type="radio" name="witid"
value="<%=vo.getWitId()%>" onClick="javascript:_modify('<%=vo.getWitId()%>','<%=name%>','<%=memo%>')"/></div>
</td>
<td bgcolor="#FFFFFF" class="blue3-12" align="center"><%=i+1%></td>

<td bgcolor="#FFFFFF" class="blue3-12">
<div align="center"><%=name%></div>
</td>
<td bgcolor="#FFFFFF">
<table border="0" align="center" cellpadding="0" cellspacing="0">
<tr>
<td class="blue3-12"><%=memo%></td>
<td></td>
</tr>
</table>
</td>
</tr>
<%}%>
<tr>
<td height="26" colspan="6" bgcolor="#E0EDF8">
<%@ include file= "/include/defaultPageScrollBar.jsp" %>
</td>
</tr>
</table>
</td>
</tr>
</table>
<table width="100%" height="50" border="0" align="center"
cellpadding="0" cellspacing="0">
<tr>
<td height="50" align="center">
<table width="400" height="100%" border="0" cellpadding="0"
cellspacing="0">
<tr align="center">


<td width="50%"><input name="delete" type="button" class="word4"
value="删除" onClick="javascript:_delete();"></td>
</tr>
</table>
</td>
</tr>
</table><table width="983" border="0" cellpadding="0" cellspacing="0" align="center">
  <tr>
   <td height="10" colspan="2"> </td>
  </tr>
  <tr>
   <td bgcolor="#FFFFFF"> </td>
    <td valign="top">
       <TABLE  cellpadding="2" cellspacing="1" width="983" align=center border=0 class="table_bgcolor">
           <TR>
             <td height="24" colspan="2" class="block_title">
<div align="center">
             值班信息分类详细信息
             </div>
</td>
           </TR>
<TR>
<td width="15%" height="20" class="message_title_bold" bgcolor="#FFFFFF">
<div align="left">值班信息分类名称</div>
</td>
<td width="85%" bgcolor="#FFFFFF" class="blue3-12-b">
<table border="0" cellspacing="0" cellpadding="0">
<tr>
<td><div align="right" class="blue3-12-b">
<div align="right">

</div>
</div>
</td>
<td>
<div align="right" class="blue3-12-b" >
<div align="right">
<input name="type_name" type="text" size="30" notnull="不能为空" title="值班信息分类名称">
</div>
</div>
</td>
</tr>
</table>
</td>
         </TR>
         <TR>
<td width="10%" height="20"  class="blue3-12-b" bgcolor="#FFFFFF">
<div align="left">说明</div>
</td>
<td width="90%" bgcolor="#FFFFFF" class="blue3-12-b">
<table border="0" cellspacing="0" cellpadding="0">
<tr>
<td><div align="right" class="blue3-12-b">
<div align="right">

</div>
</div>
</td>
<td>
<input name="type_desc" type="text" size="60" notnull="不能为空" title="值班信息分类描述">
</td>
</tr>
</table>
</td>
         </TR>
</table>
</td>
</tr>
</table>
<table width="100%" height="20" border="0" align="center"
cellpadding="0" cellspacing="0">
<tr>
<td height="20" align="center">
<table width="400" height="100%" border="0" cellpadding="0"
cellspacing="0">
<tr align="center">
<td width="50%"><input name="newtype" type="button" class="word6"
value="新增" onClick="javascript:_save(1);"></td>
<td width="50%"><input name="Submit" type="button" class="word6"
value="保存" onClick="javascript:_save(2);"></td>
</tr>
</table>
</td>
</tr>
</table></form>
</body>
</html>

现在只能取出<jsp:include page= "/include/top.jsp" /> 里面的top.jsp里面的内容，其他的就是一片白

日志上告诉我：未捕获到servlet /zbs/yjs_duty/YjsdutyTypeManageList.jsp的其中一个服务方法抛出的异常： java.lang.NullPointerException

lz
你的jsp页面显示是白页还是有错误信息如果白页那就查后台错误

是白页。看了后台日志，看不太懂就告诉我：未捕获到servlet /zbs/yjs_duty/YjsdutyTypeManageList.jsp的其中一个服务方法抛出的异常： java.lang.NullPointerException
是不是问题就是出在jsp上了，servlet应该没问题吧

把你的jsp页面代码部分部分的屏蔽来测试找出错误点

这代码看的头痛第一步看看你后台是否取到数据。如果取到了你需要的值新开一个页面只做获取操作，如果也没有问题再去你现在的jsp页面一个一个的获取如果再有问题你看看你的jsp页面是否少了某个标签的结束符号这个问题慢慢找

找到问题了，是因为include了另一个jsp文件才这样的，可是还是不知道为什么

调试易

跳转到jsp后显示不出页面

解决方案 »