JSP报错http status 500 ,请帮忙解决，谢谢

a0205 2006-05-10 03:12:27

<%@page contentType="text/html;charset=GBK"%>
<%@page import="java.sql.*"%>
<jsp:useBean id="conn" scope="page" class="test.exam"/>
<%@ include file="/public/checkvalidstudent.jsp"%>
<%!
ResultSet rs = null; // 执行Sql语句返回的结果集
String sql = "";
String classid = "";
String classname = ""; // 测试班级名称
int examtime = 0; // 考试时间
int total_question_in_paper; // 每份试卷中的考题数目
int total_paper_num=0; // 试卷总数
int paper_array[];
int curr_paperid=0; // 当前命中的试卷号
%>

<%
classid = request.getParameter("classid");

if(classid == null) {
out.println("系统错误, 无正确的班级ID号！");
return;
}

sql = "select * from test_classinfo where classid='" + classid + "'";
try {
rs = conn.executeQuery( sql );
}catch(Exception ee) {
out.println("<center>");
out.println("访问课程信息出错！请将以下信息告知系统管理员。<br>");
out.println(ee.toString() + "<br>");
out.println("<a href=javascript:history.back()>单击这里返回</a>");
out.println("</center>");
}
if(!rs.next()) {
out.println("数据库中没有课程信息，无法进行考试！");
return;
}
classname = rs.getString("classname");
examtime = rs.getInt("totaltime");
total_question_in_paper = rs.getInt("totalques");
total_paper_num = rs.getInt("totalpaper");

// 下面从班级代码为classid的试卷中随机抽取一套，进行考试
sql = "select distinct paper_id from test_paper_info where classid='" + classid + "'";
rs = conn.executeQuery( sql );
if(!rs.next()) {
out.println("还没有班级代号为 " + classid + " 的试题，请联系管理员！");
return;
}

paper_array = new int[total_paper_num];
int index=0;
do{
paper_array[index++] = rs.getInt("paper_id");
}while(rs.next());
curr_paperid = paper_array[(int)Math.floor(Math.random()*total_paper_num)];
session.setAttribute("paperid",""+curr_paperid);
session.setAttribute("classid",""+classid);

sql = "select * from TEST_PAPER_INFO where paper_id=" + curr_paperid;
rs = conn.executeQuery( sql );
%>

<html>
<head>
<script language="JavaScript">
var hours
hours=0
var minutes
minutes=0
var seconds
seconds=1
function show1(){
var Digital=new Date()
var shours=Digital.getHours()
var sminutes=Digital.getMinutes()
var sseconds=Digital.getSeconds()
var dn="AM"
if (shours>12){
dn="PM"
shours=shours-12
}
if (shours==0)
shours=12
if (sminutes<=9)
sminutes="0"+sminutes
if (sseconds<=9)
sseconds="0"+sseconds
var sctime="<b><font face='Verdana' color='#8000FF'>"+shours+":"+sminutes+":"+sseconds+" "+dn+"</font></b>"
if (!document.all)
document.write(sctime)
else
tick1.innerHTML=sctime
}

function show2(){

seconds=parseInt(seconds)+1
minutes=parseInt(minutes)+0
hours=parseInt(hours)+0

if (parseInt(seconds)==60){
minutes=parseInt(minutes)+1
seconds=0
}
if (parseInt(minutes)==<%=examtime%>){
alert("考试时间到!")
document.form1.submit()
return;
}

if (parseInt(minutes)==60){
hours=parseInt(hours)+1
minutes=0
}
if (minutes<=9){
if (seconds<=9){
var ctime="<b><font face='Verdana' color='#8000FF'>0"+hours+":0"+minutes+":0"+seconds+"</font></b>"
}else{
var ctime="<b><font face='Verdana' color='#8000FF'>0"+hours+":0"+minutes+":"+seconds+"</font></b>"
}
}else{
if (seconds<=9){
var ctime="<b><font face='Verdana' color='#8000FF'>0"+hours+":"+minutes+":0"+seconds+"</font></b>"
}else{
var ctime="<b><font face='Verdana' color='#8000FF'>0"+hours+":"+minutes+":"+seconds+"</font></b>"
}
}

if (!document.all)
document.write(ctime)
else
tick2.innerHTML=ctime
}

function loadclock(){
if (document.all)
show1()
setInterval("show2()",1000)
}
if (!document.all)
show2()
</script>

<Script Language=javascript >
function Click(){
if(event.button==2){alert
('您不需要使用右键！');
}}
document.onmousedown=Click;
</Script>
<title>入学测试试题</title>
<link rel="stylesheet" href="../public/style.css">
</head>

<body bgcolor="#FFFFFF" onLoad="Javascript:loadclock()" background="../images/bg3.gif">
<center>
<table width="756" border="0">
<tr>
<td rowspan="2" valign="bottom"><b><font size="4" color="#FF0000"><%=classname%>入学测试</font></b>

</td>
<td width="125">
<div align="left"><b>考试时间</b>：<br>
<b><font face="Verdana" color="#8000FF" size="2"><%=examtime%> </font></b><font face="Verdana" color="#8000FF"><b>minutes</b></font></div>
</td>

<td width="125"> <b>开始时间</b>：<br>
<span id=tick1></span> </td>
<td width="125"> <b>使用时间:</b><br>
<span id=tick2></span> </td>
</tr>
</table>
<hr size="1">

<form name="form1" method="post" action="getscore.jsp" target="_top">
<table width="400" border="0" align="center">
<tr>
<td><%=classname%>入学测试</td>
</tr>
</table>

<%
int question_index=1;
int tmp_questionid=0;
while(rs.next()) {
tmp_questionid=rs.getInt("QUESTIONID");
%>
<table width="75%" border="0">
<%
if(rs.getInt("selectid")==1) {
%>
<tr>
<td width="15%" align="left" valign="top">答案</td>
<td width="85%"><%="<font color=blue>(" + question_index + ")</font> " + rs.getString("qname")%>(单选题)</td>
</tr>
<tr>
<td> <input type="radio" name="<%=tmp_questionid%>" value="A">A</td><td><%=rs.getString("choice1")%></td></tr>
<tr>
<td> <input type="radio" name="<%=tmp_questionid%>" value="B">B</td><td><%=rs.getString("choice2")%></td></tr>
<tr>
<td> <input type="radio" name="<%=tmp_questionid%>" value="C">C</td><td><%=rs.getString("choice3")%></td></tr>
<tr>
<td> <input type="radio" name="<%=tmp_questionid%>" value="D">D</td><td><%=rs.getString("choice4")%></td></tr>
<%
}else {
%>
<tr>
<td width="15%" align="left" valign="top">答案</td>
<td width="85%"><%="<font color=blue>(" + question_index + ")</font> " + rs.getString("qname")%><font color=red>(多选题)</font></td>
</tr>
<tr>
<td> <input type="checkbox" name="<%=tmp_questionid%>" value="A">A</td><td><%=rs.getString("choice1")%></td></tr>
<tr>
<td> <input type="checkbox" name="<%=tmp_questionid%>" value="B">B</td><td><%=rs.getString("choice2")%></td></tr>
<tr>
<td> <input type="checkbox" name="<%=tmp_questionid%>" value="C">C</td><td><%=rs.getString("choice3")%></td></tr>
<tr>
<td> <input type="checkbox" name="<%=tmp_questionid%>" value="D">D</td><td><%=rs.getString("choice4")%></td></tr>
<%}%>
</table><p></p>
<%
question_index++;
}
%>
<p align="center">
<input type="hidden" name="totaltime" value="0">
<input type="button" name="submita" value="提交答卷" onclick="JavaScript:subit()">
</p>
</form>
</center>
</body>
</html>
<script language="JavaScript">
function subit(){
if ((confirm("你确定提交试卷吗？\n点“确定”提交，点“取消”返回检查"))==true){
document.form1.totaltime.value = minutes;
document.form1.submit();
}
}
</script>

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