表单删除问题(急)
wjneu 2004-05-12 03:14:12 两个页面leavewords.jsp和dele.jsp
leavewords.jsp代码:
<%@pagelanguage="java"%>
<%@page import="java.sql.*"%>
<jsp:useBean id="str" class="test.str_filter" scope="page"/>
<jsp:useBean id="data" scope="session" class="sql_connection.sql_connection"/>
<html>
<head>
<title>单条留言</title>
</head>
<body>
<%
String id=request.getParameter("id");
String sql="SELECT*FROM lwtable where lwid="+id;
ResultSet rs = data.executeQuery(sql);
rs.next();
%>
<center>
<h1>查看单条留言</h1>
<hr>
<table width="80%" border="1">
<tr>
<td width="50%">留言者:
<%=rs.getString("lwauthor")
%></td>
<td width="50%">留言日期<%=rs.getDate("lwdate")
%>
</td>
</tr>
<tr>
<td colspan="4">
<p>留言内容:</p>
<p><%=str.strtochn(rs.getString("lwcontent"))
%>
</p>
</td>
</tr>
<%sql="SELECT*FROM lwtable where pid="+id+"order by lwdate desc";
rs.close();
rs=data.executeQuery(sql);
%>
</table>
<hr>
<%//title="Re-->"+title;
%>
<form name="form1" method="post" action="reply.jsp?id=<%="lwid"%>">
<p>请您回复留言:</p>
<p>
<textarea name="content" rows="8" cols="80"></textarea>
</p>
<p> </p>
<input type="submit" name="Submit" value="回复">
<a href="leavewords.jsp">返回主页</a>
</center>
</body>
</html>
dele.jsp代码
<%@page contentType="text/html;charset=Gb2312"
import="java.sql.*,java.util.Date"%>
<jsp:useBean id="data" scope="session" class="sql_connection.sql_connection"/>
<html>
<head>
<title>delete</title>
</head>
<body>
<center>
<font size="5" color="blue">delete</font>
</center>
<hr>
<%
String id=request.getParameter("id");
String sql="delete from lwtable where lwid="+id;
ResultSet rs = data.executeQuery(sql);
rs.next();
//out.print(rs.getString("lwtitle"));
%>
</body>
</html>
异常信息:
exception
org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:358)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
root cause
java.lang.NullPointerException
org.apache.jsp.dele_jsp._jspService(dele_jsp.java:75)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:133)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:311)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
不知错在哪儿?该怎么改,请高手指点