tomcat+sql2000 jsp 数据库连接出现问题

你从第一行开始搜索，看看con的声明语句在哪里吧！也许是大小写问题，也许你的叫 conn

在jsp上搞连接哦.
代码贴出来看看

package com.bwm.db;import java.sql.*;/**
*class explain:Database connection
*set up name: crazyadept
*set up time: 11/22/2004
*/
public class Conn {
    private static Connection con;
    private Statement stmt;
    private ResultSet rs;
    private static final String drivername ="com.microsoft.jdbc.sqlserver.SQLServerDriver";
    private static final String url = "jdbc:microsoft:sqlserver://127.0.0.1:1433;DatabaseName=db_Job;user=kobe;password=;";    /**
     *method explain:   Get Connection DataBase
     *modify time: 12/20/2004
     */
    public static synchronized Connection getCon() throws Exception {
        try {
            Class.forName(drivername);
            con = DriverManager.getConnection(url);
            return con;
        } catch (SQLException e) {
            System.err.println(e.getMessage());
            throw e;
        }
    }    /**
     *output parameter: in order select in SQL
     *modify time: 12/20/2004
     */
    public Statement getStmtread() {
        try {
            con = getCon();
            stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                                       ResultSet.CONCUR_READ_ONLY);
            return stmt;
        } catch (Exception e) {
            System.err.println(e.getMessage());
            e.printStackTrace();
        }
        return null;
    }    /**
     *output parameter: Data
     *input parameter:  SQL select sentence
     *modify time:      11/29/2004
     */
    public ResultSet getRs(String sql) {
        try {
            stmt = getStmtread();
            rs = stmt.executeQuery(sql);
            return rs;
        } catch (Exception e) {
            System.err.println(e.getMessage());
            e.printStackTrace();
        }
        return null;
    }    /**
     *output parameter: not in order select in str SQL
     *modify time:      11/29/2004
     */
    public Statement getStmt() {
        try {
            con = getCon();
            stmt = con.createStatement();
            return stmt;
        } catch (Exception e) {
            System.err.println(e.getMessage());
            e.printStackTrace();
        }
        return null;
    }    /**
     *method explain:   Close DataBase Connection
     *modify time:      11/29/2004
     */
    public synchronized void close() {
        try {
            if (rs != null) {
                rs.close();
                rs = null;
            }
        } catch (Exception e) {
            System.err.println(e.getMessage());
            e.printStackTrace();
        }
        try {
            if (stmt != null) {
                stmt.close();
                stmt = null;
            }
        } catch (Exception e) {
            System.err.println(e.getMessage());
            e.printStackTrace();
        }
        try {
            if (con != null) {
                con.close();
                con = null;
            }
        } catch (Exception e) {
            System.err.println(e.getMessage());
            e.printStackTrace();
        }
    }
}这个是数据库连接的文件！！！
忘了把这个给出来了

<%@ page contentType="text/html; charset=gb2312" %>
<%@ page import="java.sql.*"%>
<jsp:useBean id="Conn" class="com.bwm.db.Conn" scope="page"/>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<link href="css/default.css" rel="stylesheet" type="text/css">
</head>
<body background="images/bg.jpg">
<table width="100%"  border="0" cellspacing="0" cellpadding="0">
  <tr>
    <td height="27" colspan="3" align="right"><div id="link"></div></td>
  </tr>
  <tr>
    <td width="1" height="36" background="images/gbnavl.gif"></td>
    <td width="99%" background="images/gbnavm.gif"><div id="link1"><a href="student/">学生注册</a> <a href="company/">企业注册</a></div></td>
    <td width="1" background="images/gbnavr.gif"></td>
  </tr>
</table>
<table width="100%"  border="0" cellspacing="0" cellpadding="0">
  <tr>
    <td height="50"  bgcolor="#FFFFFF"><div id="top"><img src="images/top.gif" width="340" height="38"></div></td>
  </tr>
</table>
<table width="100%" height="400"  border="0" cellpadding="0" cellspacing="0">
  <tr>
    <td valign="top" bgcolor="#FFFFFF"><table width="100%"  border="0" cellspacing="0" cellpadding="0">
      <tr align="center" >
        <td width="50%" height="22"><div id="font1">学生求职</div></td>
        <td width="50%" height="22"><div id="font1">企业招聘</div></td>
      </tr>
      <tr>
        <td valign="top"><table width="100%"  border="0" cellspacing="0" cellpadding="0">
<%
ResultSet rs=con.getRs("SELECT a.jobid,b.name,b.school,b.specialty,b.knowledge,a.job,a.emolument FROM tb_sjob AS a,tb_student AS b WHERE a.sname=b.sname and getdate()<=atime ORDER BY ptime DESC");
        while(rs.next()){
%>
      <tr>
        <td valign="top"><font id="reg"><<</font><a target="_blank" href="view.jsp?sid=<%=rs.getString(1)%>">[<%=rs.getString(2)%>]毕业于[<%=rs.getString(3)%>，<%=rs.getString(4)%>，<%=rs.getString(5)%>]，欲求[<%=rs.getString(6)%>]职位，要求薪水[<%=rs.getString(7)%>]。</a> </td>
      </tr>
<%
        }
        con.close();
%>
      <tr>
        <td> </td>
      </tr>
    </table></td>
        <td valign="top"><table width="100%"  border="0" cellspacing="0" cellpadding="0">
<%
rs=con.getRs("SELECT a.jobid,b.name,b.manage,a.job,a.emolument FROM  tb_cjob AS a,tb_company AS b WHERE a.cname=b.cname and getdate()<=atime ORDER BY ptime DESC");
        while(rs.next()){
%>
      <tr>
        <td valign="top"><font id="reg">>></font><a  target="_blank" href="view.jsp?cid=<%=rs.getString(1)%>">[<%=rs.getString(2)%>]主要经营[<%=rs.getString(3)%>]，招聘[<%=rs.getString(4)%>]职位，承诺薪水[<%=rs.getString(5)%>]。</a></td>
      </tr>
<%
        }
        con.close();
%>
      <tr>
        <td> </td>
      </tr>
    </table></td>
      </tr>
    </table></td>
    <td width="180" rowspan="2" valign="top" bgcolor="#F5f7f7"><table width="100%"  border="0" cellspacing="0" cellpadding="0">
          <tr>
        <td><table width="100%"  border="0" cellspacing="0" cellpadding="0">
          <tr>
            <td height="22" colspan="2" align="center"  background="images/tdbg.jpg"><div id="font1">登录入口</div></td>
          </tr>
          <form name="form1" method="post" action="login.jsp"><tr>
            <td width="37%" height="22" align="center">用户名：</td>
            <td width="63%">
              <input name="username" type="text" size="12">
            </td>
          </tr>
          <tr>
            <td height="22" align="center">密  码：</td>
            <td height="22"><input name="password" type="password" size="12"></td>
          </tr>
          <tr align="center">
            <td height="30" colspan="2">
              <input name="select" type="radio" value="student" checked >
              学生
              <input type="radio" name="select" value="company">
              企业</td>
          </tr>
          <tr align="center">
            <td height="30" colspan="2">
              <input type="submit" name="Submit2" value="进入">
               
<input name="Submit" type="reset" value="重置"></td>
          </tr></form>
        </table></td>
      </tr>
<tr>
        <td><table width="100%"  border="0" cellpadding="0" cellspacing="0" background="images/tdbg.jpg" >
          <tr>
            <td height="27"><div id="font1">友情链接</div></td>
          </tr>
<%
rs=con.getRs("SELECT address,name FROM tb_flink");
        while(rs.next()){
%>
          <tr>
            <td height="22"><div id="link2"><a href="<%=rs.getString(1)%>" target="_blank"><%=rs.getString(2)%></a></div></td>
          </tr>
<%
        }
        con.close();
%>
        </table></td>
      </tr>
      <tr>
        <td> </td>
      </tr>
    </table></td>
  </tr>
</table>
<table width="100%" height="50"  border="0" cellpadding="0" cellspacing="0">
  <tr>
    <td height="1"bgcolor="#FFFFFF"><hr size="1" color="#CC3300" style="position:absolute;"></td>
  </tr>
  <tr>
    <td bgcolor="#FFFFFF"> <a href="mailto:[email protected]">联系本站</a> | <a href="admin/">管理员入口</a> | ©2004 MingRi </td>
  </tr>
</table>
</body>
</html>index.jsp  文件里的内容

Unable to compile class
类引入没?

<%
ResultSet rs=con.getRs("SELECT a.jobid,b.name,b.school,b.specialty,b.knowledge,a.job,a.emolument FROM tb_sjob AS a,tb_student AS b WHERE a.sname=b.sname and getdate() <=atime ORDER BY ptime DESC");
while(rs.next()){
%> con在哪申明的在用之前没看到啊

多谢提点改过之后，出现了另外一个错误。type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException: Exception in JSP: /index.jsp:3532:       <tr>
33:         <td valign="top"><table width="100%"  border="0" cellspacing="0" cellpadding="0">
34: <%
35: ResultSet rs=con.getRs("SELECT a.jobid,b.name,b.school,b.specialty,b.knowledge,a.job,a.emolument FROM tb_sjob AS a,tb_student AS b WHERE a.sname=b.sname and getdate()<=atime ORDER BY ptime DESC");
36:         while(rs.next()){
37: %>
38:       <tr>
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:451)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:355)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause javax.servlet.ServletException: com/microsoft/jdbc/base/BaseDriver
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:841)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:774)
org.apache.jsp.index_jsp._jspService(index_jsp.java:225)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:331)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause java.lang.NoClassDefFoundError: com/microsoft/jdbc/base/BaseDriver
java.lang.ClassLoader.defineClass1(Native Method)
java.lang.ClassLoader.defineClass(Unknown Source)
java.security.SecureClassLoader.defineClass(Unknown Source)
java.net.URLClassLoader.defineClass(Unknown Source)
java.net.URLClassLoader.access$000(Unknown Source)
java.net.URLClassLoader$1.run(Unknown Source)
java.security.AccessController.doPrivileged(Native Method)
java.net.URLClassLoader.findClass(Unknown Source)
java.lang.ClassLoader.loadClass(Unknown Source)
sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
java.lang.ClassLoader.loadClass(Unknown Source)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1277)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1208)
java.lang.ClassLoader.loadClassInternal(Unknown Source)
java.lang.Class.forName0(Native Method)
java.lang.Class.forName(Unknown Source)
com.bwm.db.Conn.getCon(Conn.java:24)
com.bwm.db.Conn.getStmtread(Conn.java:39)
com.bwm.db.Conn.getRs(Conn.java:57)
org.apache.jsp.index_jsp._jspService(index_jsp.java:85)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:331)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.25 logs.

你的程序一团糟，看得出是新手写的。呵呵呵。主要问题有
1 我们根本没看到 com/microsoft/jdbc/base/BaseDriver ，你是不是修改了
[code=INIFile]drivername   ="com.microsoft.jdbc.sqlserver.SQLServerDriver"; [/code]
这个是正确的，你改他干吗？2 你的JSP最前面
<jsp:useBean   id="Conn"   class="com.bwm.db.Conn"   scope="page"/>
这里id是 Conn, 可是你调用时确是 con, 你到底有几个Connection管理类！？？3 你的Conn代码
public   class   Conn   {
        private   static   Connection   con; 数据库连接你竟然敢用static, 你单机测试不会出问题，如果使用的人多了，就会发生莫名其妙的问题。
这里至少那个static不应该用。4 你在一个Conn里面可以调用任意多次的Statement, 可是只在最后释放一个。
程序长时间运行会出现数据库方面的访问异常，一般是Cursor的问题！

你的sql的驱动放到期tomcat中没.如果没指定目录是放到bin下

真感谢大家的支持我确实是个新手啊。。而且太笨了。。
尤其谢谢这位 Java2000_net的朋友你们都是我的前辈了！！不过早上提的问题经过大家的判断，估计是我还是不懂的如何改动
这个程序在我一个同学那是可以运行的。。
就是不知道我这边为什么不行他是什么都没改动的我在想是不是数据库连接驱动的问题。。
在数据库连接的时候需要注意些什么问题吗？
跟版本有关吗还是跟tomcat的版本有关

我新发了一个帖子，是Tomcat5.5+SqlServer2000的数据源配置，也有连接数据库的代码，你可以参考一下！http://topic.csdn.net/u/20080203/14/c86c4dbf-5ea8-4ef1-a5d7-436de39d69c3.html我这个只是获取了数据库的连接，后面的应用我还没有写完，你先自己摸索吧！唯一提示的，就是，数据库连接和Statement,ResultSet 需要的时候获取，用完了马上close(); 切记。否则你以后麻烦不断！单机没问题，因为只有一个用户。

不要把jsp搞的像asp一样，看见jsp页面里写这么java代码，写这些也就算了，还加了这么多sql语句，妈的，看了就累

感谢13楼的热情提示，我这里有再把jdbc的驱动给加了进去，后来就出现另外一个错误
是空指针的问题，我以为要把rs初始化，但是还是不行type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException: Exception in JSP: /index.jsp:3633:         <td valign="top"><table width="100%"  border="0" cellspacing="0" cellpadding="0">
34: <%
35:  ResultSet rs=con.getRs("SELECT a.jobid,b.name,b.school,b.specialty,b.knowledge,a.job,a.emolument FROM tb_sjob AS a,tb_student AS b WHERE a.sname=b.sname and getdate()<=atime ORDER BY ptime DESC");
36:         while(rs.next()){
37: %>
38:       <tr>
39:         <td valign="top"><font id="reg"><<</font><a target="_blank" href="view.jsp?sid=<%=rs.getString(1)%>">[<%=rs.getString(2)%>]毕业于[<%=rs.getString(3)%>，<%=rs.getString(4)%>，<%=rs.getString(5)%>]，欲求[<%=rs.getString(6)%>]职位，要求薪水[<%=rs.getString(7)%>]。</a> </td>
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:451)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:373)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause java.lang.NullPointerException
org.apache.jsp.index_jsp._jspService(index_jsp.java:86)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:331)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.25 logs.这里出现rs出现空集，是什么问题到底？

呵呵！你怎么老是猜错呢！
你不会把 rs 打印出来看看？System.out.println("Connection="+con);
ResultSet rs=con.getRs。
System.out.println("ResultSet="+rs);你认为到底是 rs == null
还是 con ==null??

请问您有没有QQ，我现在还是学生，我想直接联系，请求帮忙会更好点...
您要是有空的话，请加我QQ 12271387
希望不会造成您的麻烦

呵呵！你看我的ID，难道猜不出来吗？ www.java2000.net

调试易

tomcat+sql2000 jsp 数据库连接出现问题

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