java bean 连接ACCESS出现问题 以前可以运行的,现在不行了,出错java.lang.NullPointerException 
org.apache.jsp.conndb_jsp._jspService(org.apache.jsp.conndb_jsp:68) 
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:99) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:802) 
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:325) 
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291) 
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:802) 请哪们高手指点一下 
package student; 
import java.sql.*; 
public class conn{ 
String sDBDriver="sun.jdbc.odbc.JdbcOdbcDriver"; 
String sConnStr="jdbc:odbc:student"; 
Connection connect =null; 
ResultSet rs =null; 
public conn(){ 
try{ 
Class.forName(sDBDriver); 

catch(java.lang.ClassNotFoundException e) 

System.err.println(e.getMessage()); 


public ResultSet executeQuery(String sql) 

try{ 
connect=DriverManager.getConnection(sConnStr); 
Statement stmt=connect.createStatement(); 
rs=stmt.executeQuery(sql); } 
catch(SQLException ex) 

System.err.println(ex.getMessage()); 

return rs; 
} } <%@ page contentType="text/html; charset=GBK" %> 
<%@ page language="java" import="java.sql.*" %> 
<jsp:useBean id="connDbBean" scope="page" class="student.conn"/> 
<html> 
<body> 
<table width="500" height="72" border="1" cellpadding="0" cellspacing="0"> 
<tr> 
<td> 姓名</td> 
<td>性别</td> 
<td>分数</td> 
</tr> 
<% 
ResultSet RS_result=connDbBean.executeQuery("select * from table1"); 
String studentName=""; 
String studentSex=""; 
int studentScore=0; 
while(RS_result.next()) 

studentName=RS_result.getString("name"); 
studentSex=RS_result.getString("sex"); 
studentScore=RS_result.getInt("score"); 
%> 
<tr> 
<td><%= studentName %></td> 
<td><%= studentSex %></td> 
<td><%= studentScore %></td> </tr> 
<% 

RS_result.close(); %> 
</table> 
</body> 
</html> 以前可以运行的,现在不行了,出错java.lang.NullPointerException 
org.apache.jsp.conndb_jsp._jspService(org.apache.jsp.conndb_jsp:68) 
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:99) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:802) 
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:325) 
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291) 
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241) 
javax.servlet.http.HttpServlet.service(HttpServlet.java:802) 请哪们高手指点一下 
我测试了一下,是RS_result为NULL 
java.lang.NullPointerException错误提示也是说空指针错误啊 
可是为什么是空啊
我用JAVA可以连接数据库的